Is WEIGHT GAIN caused by genetics or not? **For my Paper**

MrsRatfire

Your not! I appreciate it. I did mess it up. But now, I think I have got it! Best wishes. I love your photo- you have a lovely smile1
@MrsRatFire, when you quote a post, just go under what pops up in the reply box and type your response up under everything that's already there. I'm having a hard time following all of this. This is a sincere attempt to help; not trying to be rude.
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Mr_Knight

...the obesity can be overcome through exercise and portion control ...

Only if your genetics allow you to make those choices.

MrsRatfire

Your post is well written and brings up valid points. Even those of us like me and the other young lady in a similar boat do better with measuring and logging. That is why, I am sure, both of us are here. Best selling weight loss books are frequently about "the magic bullet" that will work for everyone! If that were true, we would not see this huge increase in weight in the population.

After so many crash diets and exercise programs I did for many years, the medical condition finally had enough symptoms to even know I had one. The theory of my parents are fat, therefore I am fat with no hope- is agreed, flawed logic. I had to learn my limits on how many carbs I could delete, how much food I could or could not eat, by trial and error. And the errors at time, sent me to an ER- in muscle contortions screaming in pain. I almost died, 5 times now! My chest was once being contracted by what seemed like a boa constrictor and I was gasping for air. This particular incident, went on and on all night- and it happened from me not eating enough carbs for about 5 days in my diet. (August 2013) Therefore, I track and log. These data sites are wonderful, it sure beats looking everything up in a book and jotting it down. Unfortunately, no matter how much effort, I will probably never be the ideal weight again- due to my age and progression of the disorder. but that is OKAY now. I will track and log and impact it as positively as I can.

The muscle system requires a ton of energy to function. Which is why muscle problems are frequent and a prominent hallmark to anyone who does not metabolize their food due to a genetic disorder. As we age, it gets worse. If I do to many household chores- I go into spasms. If I run more than two errands in a day, I go into spasms. And it is not the "ouch", I have a charley horse. It is every muscle in my body reacting to the lack of fuel- I crumple up into contortions and scream like a woman in labor. Which of course, labor is muscle contractions. During these episodes, I drink water by the ton…..it has to be brought to me. I have been alone and crawled across the floor, dragging myself- grappling up to the counter and pulling myself up, legs, hips, back, torso all in horrible spasms to get it myself. I eat teaspoons of salt and sugar trying to get my body fuel. And yes, consume all electrolytes which I take on a regular basis.

I get smaller spasms daily, but I have what is normal for me, at this time. As I get older, it increases, but I consider a certain amount manageable. Genetics is very complex and there are so many diseases and disorders, many which are not identified yet. There is little to no protocol or medicines for them. Just addressing symptoms and tracking every morsel and changing as your condition changes. No, I will not conquer it, I can only manage it. And yes, I have an overage of weight which I have dedicated a life time to changing, and still am.

My geneticist has me on Ubiquinel Co-Q-10, Alpha Lipolic Acid and Carnitine. All over the counter, and all things that are common for metabolic disorders in an attempt to improve the conversion into fuel. All other medications are in response to symptoms only beyond that.

The testing for these disorders is so ungodly expensive- mine they still want to do are $ 20,000. Insurance will not pay for it as I am an adult. Children can usually get the testing, but they do not approve adults. That leaves us in the shot gun approach. I have had some testing done- which led to the diagnoses, but it is not complete.

Genetics are changing now. The labs are all specialty labs and there are few in the world and the country. But, there was progress in the technology and it is my geneticists understanding that the prices will come down as more labs open. It will still be on me to pay it, but it will be cheaper. The current price of the one genome panel is 10,000, which I would not do. If it goes down to 1500 or so, I will.

Unfortunately, these disorders, metabolic, simply are not covered for adults. Which makes diagnosis often impossible. As people with my disease have liver, heat and kidney failure- that may be preventable to a point- as well as a list of symptoms that would make your hair stand up on end…..it seems cruel to me. The insurance company simply says all you have to do is be on a diet so therefore, no testing! Unless your a child. Although we have narrowed down my disorders, hence the treatment, we are not positive- I have had partial confirmation as I cannot and will not pay for it.

In a nutshell, one of my disorders is FOD (Fatty Oxidation Disorder) which is either an in ability to utilize long chain, short chain or medium chain fatty acids. The problem is, we do not know which one- so it is shot gun. And even if I eliminated them all- I would die in spasms, heart attack, whatever. We limit them, we cannot eliminate them. To make it more complex, I have a Glycogen Storage Disorder. Which means, I do not metabolize carbs well. It is the damed if you do and damned if you don't issue. These disorders are almost opposites- they each stop the metabolism of everything.

I wish I was as rare as what people think, but I am not. I am in a support group on line and there are thousands upon thousands of us who have mitochondrial and metabolic disorders.

I have spent my life beating myself up over weight- I did not know I was sick for YEARS, but finally the symptoms cut me down. I went to a funeral once by myself. A couple of losers were outside smoking- 3 guys. As I was walking up, one of them says, "Here comes Mama Cass." I can only tell you, that there will be people who put extreme effort and get diagnosed and do everything they should, and will still have people always pointing it out, that they are fat and therefore worthy of being mocked, even publicly. The public is changing, I suppose they have evolved some and are not as cruel, I hope.

The best thing all of us can do is not judge. You never know what that person is going through. All of us can decide, that if someone is overweight, to not associate with them if we choose. But just opening your mouth and taking a shot- it should be considered as bad as racism.

Thank you for your post. You are clearly educated and well balanced on the subject. Excuse my paddling on, but I thought you may find some of the nuts and bolts from a person who actually has a metabolic disorder interesting! Thank you.

Point one: Genetics play a role in an individual’s “ideal weight,” not how much they gain.
Point two: Weight gain is caused by increased caloric intake; if you eat more than you burn, you gain weight, if you eat less, you lose it. Point three: Many people focus on blaming genetics when they do not want to put in the effort it takes to lose weight or to maintain weight loss.

I haven't done any scientific experiments but I'd be shocked if it was found that genetics wasn't a factor. It's true that it's calories in minus calories out but appetitite and body types are still genetic. And no, I'm not making excuses because I'm 5'11" 175 pounds.
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Biochem grad here. I second this. Genetics definitely affects appetite, digestion, psychological components, and other contributing factors. Just because genetics doesn't directly cause weight gain doesn't mean that it isn't a significant influence. Most people accept that skin tone, hair color, and many other things are determined by genetics, but those things have environmental components as well. Just because there is an environmental component that you can somewhat control doesn't discount the fact that genetics matter.
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But you can't confuse environmental factors as part of genetics. If it genetic, then it means you are predisposition to have that destiny. Would you suggest that a person is predisposed to being overweight? I understand that medical conditions make things difficult and can throw a wrench into things until it's properly diagnosed and medicated, but regardless of the condition, you can be skinny or obese. It just depends on finding the right combination of medical and diet that works.
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People can be genetically predisposed to overeating through malfunction in the body's appetite regulation systems, i.e they never get the "full" signal when they've eaten enough so are prone to overeating. This can also happen due to damage to the hypothalamus, i.e it's not genetic it's environmental, but it still causes the person to have a tendency to overeat.

To some extent humans in general have a tendency to overeat, probably because Homo erectus didn't have a guaranteed food supply and thus people who overate when there was plenty of food and stored up fat for leaner times came through food shortages better and thus left more genes in the population. We're all the descendents of generation upon generation of people who survived food shortages - we're adapted for surviving in an environment where food was sometimes scarce and food always required effort (sometimes very strenuous effort) to acquire, not for living in a world where you can order pizza and mcdonalds over the telephone to be delivered through your living room window without even leaving the sofa. And if something is the result of natural selection, then it does come from genetics, because genes are what are passed from generation to generation and what natural selection acts upon. And when something comes from genes, there is nearly always variation. So there is definitely genetic variation in the extent to which people are predisposed to overeat. And that includes some people being predisposed to undereat - i.e. the "hard gainers" who do all kinds of weight lifting programmes and try their best to eat at a surplus but still don't gain weight because their appetite set point won't let them (and trying to eat more when you're full to the point of nausea is something no-one can do very easily).

This question is a highly complex one, and the issue of people thinking that they're the only one that finds fat loss difficult and that maintenance of a healthy weight requires effort and vigilance, or that being like this is abnormal and everyone else finds it easy, is not the same as the question as to whether some people are genetically predisposed to get fatter more easily than others.

However, going back to the OP's aim in this - whether someone's genetically predisposed to overeat more than average, that does not condemn them to a lifetime of obesity.... the obesity can be overcome through exercise and portion control (for someone prone to overeating, then exercise is probably even more important)........... the myth that "I have a genetic tendency to obesity therefore there's nothing I can do about being obese" is probably what needs to be challenged the most. Just because you're genetically predisposed to something doesn't mean it's impossible to mitigate that thing through controlling the environmental factors that interplay with the genetic factors. In the case of obesity that means ensuring an active lifestyle and good portion control.
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Jestinia

You might want to look at the genetics of satiety and the interplay of that with foods that increase appetite and perhaps contrast it with food reward behavior:

http://www.cabdirect.org/abstracts/20133398795.html;jsessionid=3E5B7F21417F77E785D934FFC33F81D0

The regulation of feeding behavior consists of a complex interaction between nutrients in the blood, peripheral hormones, neuropeptides and a number of different brain areas. Together, this system works to initiate feeding when feeling hungry and to stop eating when feeling satiated, thereby maintaining a healthy body weight in normal weight individuals. However, anorexia patients persistently override signals of hunger, whereas obese people continue to override signals of satiety. The rewarding properties of food and motivation related to food are therefore also important factors in the regulation of feeding behavior. In this chapter we will review the role of different genes in hunger and satiety signaling as well as food reward and food-motivated behavior. We will first describe the animal models that have been used to study genes involved in feeding behavior and then review the knowledge obtained from genetic studies in humans.


http://press.endocrine.org/doi/abs/10.1210/jc.2008-0472

Conclusions: We have used a unique dataset to examine the relationship between a validated measure of children’s habitual appetitive behavior and FTO obesity risk genotype and conclude that the commonest known risk allele for obesity is likely to exert at least some of its effects by influencing appetite.




If you really want to complicate it and move into relatively new areas of research, look at epigenetic possibilities. MyFitnessPal's spell check doesn't even know what the word means yet:

http://europepmc.org/abstract/MED/21036330/reload=0;jsessionid=pIenBZ9F1a77r1pUTBlT.22

The etiology of obesity is multifactorial, involving complex interactions among the genetic makeup, neuroendocrine status, fetal programming, and different unhealthy environmental factors, such as sedentarism or inadequate dietary habits. Among the different mechanisms causing obesity, epigenetics, defined as the study of heritable changes in gene expression that occur without a change in the DNA sequence, has emerged as a very important determinant. Experimental evidence concerning dietary factors influencing obesity development through epigenetic mechanisms has been described. Thus, identification of those individuals who present with changes in DNA methylation profiles, certain histone modifications, or other epigenetically related processes could help to predict their susceptibility to gain or lose weight. Indeed, research concerning epigenetic mechanisms affecting weight homeostasis may play a role in the prevention of excessive fat deposition, the prediction of the most appropriate weight reduction plan, and the implementation of newer therapeutic approaches.

MrsRatfire

And here you go again, judging me. I know nothing about you, you know nothing about me. What we do know, is I saw no humor in the posting, and you did. And you think it is important that I understand that. Ok! I am on the joy train! Gloves are off. Your understanding of what a stand-up is or is not, does not even make sense. You never as much as saw my act let alone know anything about me if you did. If you are listening, than you would know, that there is not a comic on earth that does not self- depurate to get a laugh. We all did it. There may be exceptions, but so very few. It is a job for us, to get laughs. At all expense.

But that is not what this thread should be about. No I did not find it funny. And you should refrain from labeling people you disagree with. It is a stupid internet forum, you are not a keen psychologist into the minds of people by a comment.

I will continue to like or dislike what I please. And when I get responses I consider wrong, I will answer them. As will you. You may want to lay off analyzing people in a thread. It is nonsense.

I guess that is why you have a picture of your upper body as a photo- as the strongest muscle in your body is certainly not your brain. Now don't be offended, it was just in jest! Have a thick skin if you do not like what I said, that way, you take your own advice.


For the people that claim they gain while eating at a TDEE.

No, I am not a doctor.
I DO however, understand the basic way world works in such situations.

As it goes, I do have a metabolic tester and have looked in to the area a bit.
How have you got your metabolism tested? If you have used an online calculator, but DO have issues, then the online calculator is wrong.
Despite having said metabolic tester (I'm not a very good salesman), I DO advise people that the best method to work out TDEE is CICO.

Taking from a poster above who gains on 1200 and loses on 800. If this happens consistently as an average over long periods, TDEE is probably somewhere around 1000 - certainly between the two. Of course, logging food isn't that accurate.
Many foods can be 50% unrepresented - suddenly a TDEE of 1500. HOWEVER, that doesn't matter. Because if they eat the up to a total of foods which claim to have 1000 calories and weight stays the same, that IS a useful TDEE number as it reflects their environment.

And I am happy to tell you, I was a stand-up comic for 15 years.

Then that's rather sad, to my mind. There does seem to be a trait in some stand ups that they can give it out, but not take it.
If you've been around stand ups for a good bit of time and STILL get offended by a joke which happens to hit home, then you definitely need a thicker skin, I'd say . (Appreciated British Stand Ups tend to be particularly offensive.)
So, yes, it IS about you having a thin skin, to my mind. Over the years I've been offended by many such things that could target me. Over the years I've realised I'd prefer the freedom of speech for people to say them than to restrict the things that personally offend me.
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nomeejerome

MrsRatfire:

When you hit quote to respond to somebody, go all the way to the bottom (without deleting anything) and type your response after the last /quote that will be in brackets.

MrsRatfire

I forgot to respond when you chimed in that the photo was not appropriate in this thread, at the time. I did appreciate your support. And your picture inspires awe! You look fantastic. You have faced the odds and beat them. Great job!
My parents were overweight. My mother had diabetes, they both had high blood pressure.
2 of my 4 siblings were overweight as children.
3 of my siblings are currently overweight, 2 of them have dangerously high blood pressure, one of which is only 30.
My maternal grandparents were both over weight, both with diabetes, and high blood pressure, my grandfather suffered a serious stroke.
My paternal grandmother also had high blood pressure and a minor stroke.

Several of my first cousins are not just overweight but morbidly obese, all under 40.


I have never been more than a few pounds overweight and that was related to pregnancies, and honestly it hasn't been that hard to maintain a healthy weight. I do have borderline high blood pressure though, which sucks.

So maybe there is some genetic predisposition but my genetics did not "make" me fat, obviously.
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MrsRatfire

I am shocked at how unkind several people have been to this young lady. Because you had weight and took it off, therefore, she must be wrong. She has a disorder, which she is working on to the point where she is almost goal weight! And in the universe, you have decided that what she is saying is not possible? Do you know anything about the disorder called POTS or any other disorder that can put someone in her situation. Try not to forget, that anyone with an actual disorder or mis-firing in the genetics- by a missing of defective enzyme, protein etc. has a critical illness they fight for life. Most people with metabolic disorders die rather young. Her 9 pound to lose is the least of her worries.

I certainly know nothing about many things, but I know quite a bit about genetics. You may want to read some of the abstracts and documents by the MEDICAL community- not the first thing that pops up on google about a disease such as this woman has. Be awful glad you were spared of it as well.


How the hell are you going to tell me I haven't been at a deficit and I don't gain eating my TDEE when I log EVERYTHING I put in my mouth, weigh everything, wear a pedometer, wear a HRM when I'm working out?
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Because you would be violating the laws of the universe if what you claim were true. It is *impossible* - you may as well be claiming you have a hammer that, when you drop it, floats in the air.

If your logging is telling you otherwise, there is something wrong with your logging - period. Full stop.

Sorry, but what I'm telling you is the truth.
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the truth hurts….
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MrsRatfire

She can be in this situation. You can eat low calories and exercise and still not lose weight with her disorder. Do you really know anything about it or any other metabolic disorder? I didn't. And have done YEARS of research on just a few of them and have barely scratched the surface.

He body does not utilize the fuel into useable energy. Your body will make a choice, to use the energy though the cellular process and the mitochondria as well as many other components. It will then decide to store some as fat. It will convert to muscle or the cells in the bone marrow to lay down new bone, what ever it needs, it gets coded and shipped somewhere.

Her body takes some of the fuel your body would send somewhere else, and sends it to body fat is error! Some people with these diseases are pick thin and just as ill as the bodies that go excess. Some of us oscillate this span and have been both.

A metabolic disorder is not what you pop up on google. It is not something an in office test for the metabolism with a gadget will give you an result for. It is extremely complex.

I was very surprised in this forum, how many people not only believe they are doctors, but geneticists to boot. Geneticists are usually involved in research and have multiple P.h.d's as well as M.D.'s. They are in such high demand, people travel across the country to see one. The tests are so expensive and not covered by insurance unless you are an infant or a child (in general), many people are left untreated. Often to die. Usually due to organ failure and not a clue as to what could or could not have been done.

I feel I am seeing too many expert opinions and there were more than one person, discrediting this girl. I would rather everyone please stop doing this to her. If you want someone to point at and call whatever, use me. It is much easier for me to take.

I've been at a deficit for the past 3 years and STILL gained weight because of my endocrine disorders.
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You haven't been at a deficit.

I gain eating my TDEE

No, you do not.
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LOL. How the hell are you going to tell me I haven't been at a deficit and I don't gain eating my TDEE when I log EVERYTHING I put in my mouth, weigh everything, wear a pedometer, wear a HRM when I'm working out?

I know what I do every day. You don't. So you are beyond ignorant. When you have spent years in and out of hospitals and doctors offices, seeing every specialist under the sun, having every test performed, having blood work every couple days, collecting 24 hr urine tests, undergoing MRIs, CT scans, x-rays, ultrasounds, colonoscopies, endoscopies, laparoscopies, cancer scares, etc. to find out why you've gained 100+lbs and experience the symptoms I do every day for NO REASON, THEN you can open your mouth. But until then, be quiet because your commentary isn't needed, wanted, or in any way helpful.
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If you're gaining you have not...by definition...been eating at a deficit. The results determine whether or not you were eating at a deficit, eating your TDEE, or eating in a surplus, not a guess at what your TDEE should be. Estimates are just estimates regardless of your medical conditions.
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_KitKat_

Nobody has said her condition does not effect her or her weight, all they stated was the laws of energy. Due to her condition she may very well have a very low TDEE compared to others, this would make it appear that when she eats at 1200 calories she is in a 1000 calorie deficient but in reality her TDEE due to her condition is only 1000...this would then her 1200 calorie diet is actually a surplus of 200 calories a day for her. Due to how low that number is it may be near impossible to get all of her nutrients and feel full and lose weight. Knowledge in this instance has nothing to due with health it is a simple law of energy, it can not be created out of nothing and fat is a reserve of energy at its simplest form. The defensiveness of some people actually astounds me, the facts are if you have a disorder that effects your burning of energy you may very well have a close to impossible time maintaining weight let alone losing, but laws of science dictate the reason for this is you are using energy at a much reduced rate next to the population which calculators and estimates are based off....you sit outside the curb. Is this fair? NO Is this your fault? NO but it is how it is.

MrsRatfire, I applaud you for defending yourself and others but the main of this conversation seems to have been lost.

here is an excerpt stating the 3 laws of energy, and yes a calorie is a unit of energy.

"In a discussion of energy the basic understanding revolves around the fact that there are three laws. These are simple laws dealing with energy and can be defined as follows:
First Law
Energy can neither be created nor destroyed. This means that you can’t make energy out of nothing— the total amount of energy in the universe is a constant. (Please note that this applies to a closed system – the Earth is not a closed system, the Earth receives energy all the time from the Sun).
Second Law
The second law refers to the state of energy and is reflected in a measurement of the degree of disorder, (a measurement called entropy). When you burn a lump of coal, (a material in a very ordered state) a change occurs which results in a more disordered state and you can never combine the resultant products, (heat, gases, etc.) back to form that original lump of coal, (First Law). The Universe, according to scientific evidence, is winding down, the sun will eventually go out, (in billion of years so we don’t have to worry right now). In summary when we use an energy source it is not destroyed but enters a more disordered state. This makes the energy less available to us and in converting the energy to power means some loss.
Third Law
As we mentioned the universe is winding down. The third law is that everything does come to a stop only when the temperature is at −273.15°C on the Celsius scale.[1] This equates to −459.67°F. This is called absolute zero and is where the entropy measurement is 0, (Zero).
Together, these laws help form the foundations of modern science. These laws are absolute physical laws – everything in the observable universe is subject to them. Like time or gravity, nothing in the universe is exempt from these laws."

in_the_stars

Thermodynamics and weight loss

4. October 2007, 13:19 UhrMetabolism, Obesity, Weight lossmreades94 comments

4
Probably no laws of physics have been so over invoked and less understood than the laws of thermodynamics. Everyone it seems is using the laws of thermodynamics to justify every position imaginable in the field of weight loss. Journalists often throw out the laws of thermodynamics to prove or disprove dietary regimens they’re writing about. Authors of various blogs and other online sites rabbit on about how the laws of thermodynamics are aligned with their pet theories. And even worse, research scientists – who really should know better – more often than not misquote the laws of thermodynamics, especially when talking about the possibility of a dietary metabolic advantage. ‘It can’t be valid,’ they sniff, ‘it violates the laws of thermodynamics.’

So, I figured is was time to delve into these mysterious laws so that readers of this blog at least can know thermodynamic nonsense when they see it.

When you get a grasp of the laws of thermodynamics it becomes pretty easy to see how they can be confusing not only to the great unwashed masses but even to scientists who have never really taken the time to study them. Thermodynamics are seemingly simple at first glance, but the more you dig into them, the more complex they become. To see what I mean, take a look at the syllabus for the thermodynamics course at MIT and skim through a few of the lectures.


Before we jump into these laws, I want to show you why scientists typically heap scorn on anyone who claims to have somehow violated the laws of thermodynamics.

The author of a book of thermodynamics that I have writes the following:

No violation of any law of thermodynamics is known to have occurred in over 200 years of research in this area.

Most physicists consider the Second Law of Thermodynamics the most universal ‘governor’ of natural activity that has ever been revealed by scientific study.

Sir Arthur Eddington wrote in 1915

If someone points out to you that your pet theory of the universe is in disagreement with Maxwell’s equations — then so much the worse for Maxwell’s equations. If it is found to be contradicted by observation — well, these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.

And Ivan Bazarov wrote the following in a thermodynamics text from 1964:

The second law of thermodynamics is, without a doubt, one of the most perfect laws in physics. Any reproducible violation of it, however small, would bring the discoverer great riches as well as a trip to Stockholm. The world’s energy problems would be solved at one stroke. It is not possible to find any other law (except, perhaps, for super selection rules such as charge conservation) for which a proposed violation would bring more skepticism than this one. Not even Maxwell’s laws of electricity or Newton’s law of gravitation are so sacrosanct, for each has measurable corrections coming from quantum effects or general relativity. The law has caught the attention of poets and philosophers and has been called the greatest scientific achievement of the nineteenth century.

Now that you somewhat understand the strong feelings of those in the know about thermodynamics, you can see why they would disparage anyone purporting to break or repeal these laws. And it helps to understand the vituperation heaped on Robert Atkins who wrote one of the most hubristic and outright ignorant statements imaginable showing a total lack of understanding of the laws of thermodynamics when he said:

When I make this claim, that you can lose more weight on a higher number of calories, I seem to be breaking the law—one of the hallowed laws of thermodynamics. Many powers-that-be get terribly provoked when I repeal their laws. But the calorie theory is a false law that is meant to be broken, and ketosis/lipolysis is the instrument for breaking it.

As reported in Gary Taubes Good Calories, Bad Calories, this comment and others like it may have lead John Yudkin to say of Atkins’ book that its “chief consequence [may have been] to antagonize the medical and nutritional establishment.”

But, since Atkins wasn’t really a physicist, it’s easy to see how he could have become confused.

There are four laws of thermodynamics, but we’re going to concern ourselves in this post only with the first and second laws. The other two laws – the zeroth law and the fourth law involve temperature, are highly theoretical, and aren’t really relevant to the discussion at hand.

The first law of thermodynamics is the conservation of energy law and states that energy can neither be created nor destroyed. Another way of stating this law is to say that the energy of a system plus surroundings is constant in time. This first law is where the mistaken idea that ‘a calorie is a calorie’ that misguided people always want to parrot comes from. And on the surface it seems to make sense. If energy can’t be created or destroyed why wouldn’t a calorie always be a calorie? That’s where the second law comes in.

The second law of thermodynamics says that the entropy of the universe increases during any spontaneous process. What this means is that it is impossible for a system to turn a given amount of energy into an equivalent amount of work. It is this second law that is really the ‘a calorie is a calorie’ law, and, in fact, the second law shows, in terms of weight loss at least, that a calorie isn’t necessarily a calorie.

These two laws of thermodynamics can be summed up cleverly. The first law says you can’t get something for nothing, and the second law tells you that you can’t break even.

Since it’s the second law that applies to living, breathing animals, and since it is the one most often confused in the calorie issue, let’s look at it a little more closely. The second law is the law driving chemical reactions, and since we’re nothing but a bunch of walking chemical reactions it is the one that applies most to us.

The second law is a dissipation law in that it says that in any reaction that is irreversible (most of the chemical reactions that give us life) there is a loss or dissipation of energy in that reaction. If substance A converts to substance B via a chemical reaction in the body, then substance B has a lower energy than substance A. In other words energy is lost to the universe in that reaction. There is no reaction that doesn’t end up without a loss of some energy to the universe. This loss of energy is called entropy.

The second law can kind of be summed with this equation:

calories in = calories out + entropy

If we substitute numbers in the above equation it could look like this:

100 calories in = 70 calories out + entropy

If we solve this equation for entropy, we can see that entropy is 30 calories. Or, in this case, 30 calories of energy are lost.

The larger the number for entropy, the more inefficient the system is, i.e., more energy lost from the system forever.

For example, when you drive a car only about 10-12 percent of the energy contained in the gasoline actually is converted to the work of propelling the car – the rest is lost to heat (entropy). This irretrievable loss is the reason a perpetual motion machine can never be built although many have tried. No matter how efficiently such a machine might be designed it will ultimately run down because of these little energy (entropy) leaks here and there. (I’ve used entropy as if it is synonymous with energy when in technical terms it really isn’t, but it’s easier to think of it that way.)

How does this apply to weight loss?

Each of the many chemical reactions in the body end up dissipating energy. We get our energy in the form of calories from the food we eat. This energy gets consumed in all the countless chemical reactions that go on all the time. Just like an automobile, we are not all that efficient. We don’t convert calories to energy on a one to one basis because of the loss of energy to the universe described by the second law.

This is all basic stuff, but it gets interesting when we start to look at how the different macronutrients (fat, protein and carbohydrate) affect the process.

As I’ve discussed in this blog frequently, we need to maintain our blood sugar in a fairly narrow range. We need blood sugar to supply energy to certain cells that can’t use it in any other form (the red blood cells, some brain cells and others). We can get plenty of sugar into our blood and have no trouble keeping our blood sugar up if we eat carbohydrates. The carbohydrate-containing foods get broken down into their sugar molecules that are then absorbed from the intestines directly into the blood. In our high carb world our problem isn’t too little sugar but too much. But in the early years of our existence on the planet it wasn’t like this. We didn’t have access to the bounty of easily absorbed carbs that we do today, yet we still had the need for sugar in our blood. As a consequence we evolved mechanisms to convert other nutrients – primarily protein – into sugar.

If we have a diet containing plenty of carbohydrate, the carbohydrate goes into the blood as sugar. There are very few chemical reactions along the way, and there is a loss of energy to the universe with each of these reactions. But, since there aren’t many conversions, there isn’t a lot of energy loss.

If we have no carbohydrates (or few) in the diet, however, it’s a different story. In order to maintain the necessary sugar level in the blood the body is forced to make sugar out of protein, which isn’t a simple operation. Look in any basic biochemistry textbook and you can see all the reactions required to convert protein to sugar, and each one of these reactions consumes energy just to take place but loses energy to the universe in the process as well. It’s much less efficient for the body to convert protein to sugar than it is to simply take the sugar as it comes in already formed.

The second law of thermodynamics virtually mandates that there be a larger loss of energy when one has to convert protein to sugar instead of merely using the sugar as it comes in. Since there are 4 kcal of energy in a gram of sugar and 4 kcal of energy in a gram of protein, it should be apparent that less of the 4 kcal in a gram of sugar will be dissipated than will be the 4 kcal in a gram of protein if this gram of protein has to first be converted to sugar.

And, consequently, one would think that a diet low in carbohydrate and higher in protein and fat (both of which have to be converted to sugar) would bring about a greater weight loss than a diet of the same number of calories but with higher levels of carbohydrate. In fact, the second law of thermodynamics predicts this very phenomenon. But despite this rather obvious notion that complies perfectly with the second law, many ignorant people continue to cling to the idea that ‘a calorie is a calorie’ despite that idea flying in the face of the second law. I suppose these people discount the second law. If so, then they should spend their time putting together a perpetual motion machine, which, if they could, would garner them a lot more fame than their inane posturing on the inevitability of the second law might do.

A classic example of how the second law works is in the difference between regular and premium gasoline. Both regular and premium have the same exact number of calories per gallon, but premium burns more efficiently. In other words, the calories contained in the premium gas get ‘wasted’ at a lower percentage in propelling the car along the road than do the calories in the regular. A high-performance automobile designed to squeeze the most out of a gallon of gas will get better mileage on premium than on regular gasoline, yet the calories in are exactly the same.

In the human body this inefficiency can be measured as an increase in metabolic rate and an increase in body heat being produced under laboratory conditions. One would assume that since the second law is inviolable and always in operation that people eating a diet low in carbohydrates and high in protein would produce more heat than those consuming the same number of calories but composed of a much higher percentage of carbohydrates. And that is exactly what is found.

In a paper (full text here) published in the Journal of the American College of Nutrition researchers examined this effect in ten healthy young women who consumed either a high-protein, low-carbohydrate or a lower-protein, higher-carb diet of the same number of calories. The researchers used these women as their own controls, providing them with the first diet followed by measurements in the lab, then 54 days later with the second diet and lab evaluation.

Precise measurement of heat and metabolic rate showed that when the women followed the high-protein, low-carb diet they produced almost twice as much heat as they did when consuming the higher carb diet of the same calories. In the higher-carb diet the entropy was smaller than in the higher-protein diet, which would be expected from the second law.

As the authors of the paper put it:

These data demonstrate that meal-induced thermogenesis at 2.5 hours post-meal averages about twofold higher on a HP, low fat diet versus a HC, low-fat diet. Generally, postprandial thermogenesis has been associated with the protein content of a meal, and our data confirm this relationship. However, the difference in the energy cost of HP versus HC diets, particularly in the context of weight loss promotion, has not been addressed by healthcare professionals. Increased diet-induced thermogenesis, in association with the preservation of REE [resting energy expediture], may contribute to the reported weight loss success of diets high in protein with moderate levels of carbohydrate and lends credence to the observation that weight loss on HP diets is predominately body fat, not body water.

Bear all this in mind the next time you tell someone that it is possible to lose more weight on a greater number of calories as long as those calories are low-carb calories, and that someone pooh poohs you with the old ‘That can’t be possible. It violates the laws of thermodynamics. A calorie is after all a calorie.’ Ask them precisely which laws of thermodynamics it violates and ask them to tell you how. Then sit back and watch the fun.

_KitKat_

Thermodynamics and weight loss

4. October 2007, 13:19 UhrMetabolism, Obesity, Weight lossmreades94 comments

4
Probably no laws of physics have been so over invoked and less understood than the laws of thermodynamics. Everyone it seems is using the laws of thermodynamics to justify every position imaginable in the field of weight loss. Journalists often throw out the laws of thermodynamics to prove or disprove dietary regimens they’re writing about. Authors of various blogs and other online sites rabbit on about how the laws of thermodynamics are aligned with their pet theories. And even worse, research scientists – who really should know better – more often than not misquote the laws of thermodynamics, especially when talking about the possibility of a dietary metabolic advantage. ‘It can’t be valid,’ they sniff, ‘it violates the laws of thermodynamics.’

So, I figured is was time to delve into these mysterious laws so that readers of this blog at least can know thermodynamic nonsense when they see it.

When you get a grasp of the laws of thermodynamics it becomes pretty easy to see how they can be confusing not only to the great unwashed masses but even to scientists who have never really taken the time to study them. Thermodynamics are seemingly simple at first glance, but the more you dig into them, the more complex they become. To see what I mean, take a look at the syllabus for the thermodynamics course at MIT and skim through a few of the lectures.


Before we jump into these laws, I want to show you why scientists typically heap scorn on anyone who claims to have somehow violated the laws of thermodynamics.

The author of a book of thermodynamics that I have writes the following:

No violation of any law of thermodynamics is known to have occurred in over 200 years of research in this area.

Most physicists consider the Second Law of Thermodynamics the most universal ‘governor’ of natural activity that has ever been revealed by scientific study.

Sir Arthur Eddington wrote in 1915

If someone points out to you that your pet theory of the universe is in disagreement with Maxwell’s equations — then so much the worse for Maxwell’s equations. If it is found to be contradicted by observation — well, these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.

And Ivan Bazarov wrote the following in a thermodynamics text from 1964:

The second law of thermodynamics is, without a doubt, one of the most perfect laws in physics. Any reproducible violation of it, however small, would bring the discoverer great riches as well as a trip to Stockholm. The world’s energy problems would be solved at one stroke. It is not possible to find any other law (except, perhaps, for super selection rules such as charge conservation) for which a proposed violation would bring more skepticism than this one. Not even Maxwell’s laws of electricity or Newton’s law of gravitation are so sacrosanct, for each has measurable corrections coming from quantum effects or general relativity. The law has caught the attention of poets and philosophers and has been called the greatest scientific achievement of the nineteenth century.

Now that you somewhat understand the strong feelings of those in the know about thermodynamics, you can see why they would disparage anyone purporting to break or repeal these laws. And it helps to understand the vituperation heaped on Robert Atkins who wrote one of the most hubristic and outright ignorant statements imaginable showing a total lack of understanding of the laws of thermodynamics when he said:

When I make this claim, that you can lose more weight on a higher number of calories, I seem to be breaking the law—one of the hallowed laws of thermodynamics. Many powers-that-be get terribly provoked when I repeal their laws. But the calorie theory is a false law that is meant to be broken, and ketosis/lipolysis is the instrument for breaking it.

As reported in Gary Taubes Good Calories, Bad Calories, this comment and others like it may have lead John Yudkin to say of Atkins’ book that its “chief consequence [may have been] to antagonize the medical and nutritional establishment.”

But, since Atkins wasn’t really a physicist, it’s easy to see how he could have become confused.

There are four laws of thermodynamics, but we’re going to concern ourselves in this post only with the first and second laws. The other two laws – the zeroth law and the fourth law involve temperature, are highly theoretical, and aren’t really relevant to the discussion at hand.

The first law of thermodynamics is the conservation of energy law and states that energy can neither be created nor destroyed. Another way of stating this law is to say that the energy of a system plus surroundings is constant in time. This first law is where the mistaken idea that ‘a calorie is a calorie’ that misguided people always want to parrot comes from. And on the surface it seems to make sense. If energy can’t be created or destroyed why wouldn’t a calorie always be a calorie? That’s where the second law comes in.

The second law of thermodynamics says that the entropy of the universe increases during any spontaneous process. What this means is that it is impossible for a system to turn a given amount of energy into an equivalent amount of work. It is this second law that is really the ‘a calorie is a calorie’ law, and, in fact, the second law shows, in terms of weight loss at least, that a calorie isn’t necessarily a calorie.

These two laws of thermodynamics can be summed up cleverly. The first law says you can’t get something for nothing, and the second law tells you that you can’t break even.

Since it’s the second law that applies to living, breathing animals, and since it is the one most often confused in the calorie issue, let’s look at it a little more closely. The second law is the law driving chemical reactions, and since we’re nothing but a bunch of walking chemical reactions it is the one that applies most to us.

The second law is a dissipation law in that it says that in any reaction that is irreversible (most of the chemical reactions that give us life) there is a loss or dissipation of energy in that reaction. If substance A converts to substance B via a chemical reaction in the body, then substance B has a lower energy than substance A. In other words energy is lost to the universe in that reaction. There is no reaction that doesn’t end up without a loss of some energy to the universe. This loss of energy is called entropy.

The second law can kind of be summed with this equation:

calories in = calories out + entropy

If we substitute numbers in the above equation it could look like this:

100 calories in = 70 calories out + entropy

If we solve this equation for entropy, we can see that entropy is 30 calories. Or, in this case, 30 calories of energy are lost.

The larger the number for entropy, the more inefficient the system is, i.e., more energy lost from the system forever.

For example, when you drive a car only about 10-12 percent of the energy contained in the gasoline actually is converted to the work of propelling the car – the rest is lost to heat (entropy). This irretrievable loss is the reason a perpetual motion machine can never be built although many have tried. No matter how efficiently such a machine might be designed it will ultimately run down because of these little energy (entropy) leaks here and there. (I’ve used entropy as if it is synonymous with energy when in technical terms it really isn’t, but it’s easier to think of it that way.)

How does this apply to weight loss?

Each of the many chemical reactions in the body end up dissipating energy. We get our energy in the form of calories from the food we eat. This energy gets consumed in all the countless chemical reactions that go on all the time. Just like an automobile, we are not all that efficient. We don’t convert calories to energy on a one to one basis because of the loss of energy to the universe described by the second law.

This is all basic stuff, but it gets interesting when we start to look at how the different macronutrients (fat, protein and carbohydrate) affect the process.

As I’ve discussed in this blog frequently, we need to maintain our blood sugar in a fairly narrow range. We need blood sugar to supply energy to certain cells that can’t use it in any other form (the red blood cells, some brain cells and others). We can get plenty of sugar into our blood and have no trouble keeping our blood sugar up if we eat carbohydrates. The carbohydrate-containing foods get broken down into their sugar molecules that are then absorbed from the intestines directly into the blood. In our high carb world our problem isn’t too little sugar but too much. But in the early years of our existence on the planet it wasn’t like this. We didn’t have access to the bounty of easily absorbed carbs that we do today, yet we still had the need for sugar in our blood. As a consequence we evolved mechanisms to convert other nutrients – primarily protein – into sugar.

If we have a diet containing plenty of carbohydrate, the carbohydrate goes into the blood as sugar. There are very few chemical reactions along the way, and there is a loss of energy to the universe with each of these reactions. But, since there aren’t many conversions, there isn’t a lot of energy loss.

If we have no carbohydrates (or few) in the diet, however, it’s a different story. In order to maintain the necessary sugar level in the blood the body is forced to make sugar out of protein, which isn’t a simple operation. Look in any basic biochemistry textbook and you can see all the reactions required to convert protein to sugar, and each one of these reactions consumes energy just to take place but loses energy to the universe in the process as well. It’s much less efficient for the body to convert protein to sugar than it is to simply take the sugar as it comes in already formed.

The second law of thermodynamics virtually mandates that there be a larger loss of energy when one has to convert protein to sugar instead of merely using the sugar as it comes in. Since there are 4 kcal of energy in a gram of sugar and 4 kcal of energy in a gram of protein, it should be apparent that less of the 4 kcal in a gram of sugar will be dissipated than will be the 4 kcal in a gram of protein if this gram of protein has to first be converted to sugar.

And, consequently, one would think that a diet low in carbohydrate and higher in protein and fat (both of which have to be converted to sugar) would bring about a greater weight loss than a diet of the same number of calories but with higher levels of carbohydrate. In fact, the second law of thermodynamics predicts this very phenomenon. But despite this rather obvious notion that complies perfectly with the second law, many ignorant people continue to cling to the idea that ‘a calorie is a calorie’ despite that idea flying in the face of the second law. I suppose these people discount the second law. If so, then they should spend their time putting together a perpetual motion machine, which, if they could, would garner them a lot more fame than their inane posturing on the inevitability of the second law might do.

A classic example of how the second law works is in the difference between regular and premium gasoline. Both regular and premium have the same exact number of calories per gallon, but premium burns more efficiently. In other words, the calories contained in the premium gas get ‘wasted’ at a lower percentage in propelling the car along the road than do the calories in the regular. A high-performance automobile designed to squeeze the most out of a gallon of gas will get better mileage on premium than on regular gasoline, yet the calories in are exactly the same.

In the human body this inefficiency can be measured as an increase in metabolic rate and an increase in body heat being produced under laboratory conditions. One would assume that since the second law is inviolable and always in operation that people eating a diet low in carbohydrates and high in protein would produce more heat than those consuming the same number of calories but composed of a much higher percentage of carbohydrates. And that is exactly what is found.

In a paper (full text here) published in the Journal of the American College of Nutrition researchers examined this effect in ten healthy young women who consumed either a high-protein, low-carbohydrate or a lower-protein, higher-carb diet of the same number of calories. The researchers used these women as their own controls, providing them with the first diet followed by measurements in the lab, then 54 days later with the second diet and lab evaluation.

Precise measurement of heat and metabolic rate showed that when the women followed the high-protein, low-carb diet they produced almost twice as much heat as they did when consuming the higher carb diet of the same calories. In the higher-carb diet the entropy was smaller than in the higher-protein diet, which would be expected from the second law.

As the authors of the paper put it:

These data demonstrate that meal-induced thermogenesis at 2.5 hours post-meal averages about twofold higher on a HP, low fat diet versus a HC, low-fat diet. Generally, postprandial thermogenesis has been associated with the protein content of a meal, and our data confirm this relationship. However, the difference in the energy cost of HP versus HC diets, particularly in the context of weight loss promotion, has not been addressed by healthcare professionals. Increased diet-induced thermogenesis, in association with the preservation of REE [resting energy expediture], may contribute to the reported weight loss success of diets high in protein with moderate levels of carbohydrate and lends credence to the observation that weight loss on HP diets is predominately body fat, not body water.

Bear all this in mind the next time you tell someone that it is possible to lose more weight on a greater number of calories as long as those calories are low-carb calories, and that someone pooh poohs you with the old ‘That can’t be possible. It violates the laws of thermodynamics. A calorie is after all a calorie.’ Ask them precisely which laws of thermodynamics it violates and ask them to tell you how. Then sit back and watch the fun.

This was extremely interesting, on the same token...concerning this thread the basics still apply nobody is stating that the way her body uses energy is not different or that calories appear to have a different effect of her. The main point is regarding a unit of energy can not be created out of nothing therefor it came from somewhere. I am one who will normally say a calorie is a calorie but at the same time I do understand the body processes different delivery systems of the calorie differently. In the basics of weight loss and gain a calorie is a calorie but at a smaller level I can see efficiency of the calorie changing. One flaw in the article is the analogy of premium gas verse regular, they do not have the same "calories" premium gas by definition is higher octane which makes it more nutritional and energy dense because it increase combustion. Think of it like a protein shake vs skim milk shake, if the protein shake has higher calories and is more nutritionally dense the body lasts longer on it and burns it more efficiently but if the skim milk shake has lower calories and less nutrients the body doesn't get as far on it and is less efficient. Just because they are both 8oz. does not mean the same calories. So 1 gallon of 87 octane gas has less calories then 93 octane gas. This article also uses a high mpg efficient car. So yes a efficient body with a low body fat % and lean muscle will burn more efficient. But comparing the 2 is apples to oranges.

If someone was to say I have a condition that I pee out all carb calories (say their body will not process carbs) and they ate 500 calories in carbs over TDEE, most would say they would gain weight but they are expelling the surplus it still went somewhere (wasted energy). The same as if someone has a condition that will only convert carb calories to fat (this is still using the calorie) and refuses to use them as energy, because of the definition of TDEE as being the amount of energy the body uses...by definition the body is still using the calorie (a unit of energy) and it originally had to come from somewhere because of the first law of energy.

If my thoughts are hard to follow sorry, I do believe in a efficient vehicle (the body) the type of unit that the calorie came from will effect the efficiency of the metabolism but on an inefficient build and the body has excess the difference would be too small to gage. Also a protein calorie builds muscle that makes it more efficient because muscle burns more calories than fat. In energy usage this actually makes it inefficient but for what our preferences are ( to burn as much energy as possible in the least time, we want to be gas guzzlers) it makes it a plus for us.

sk_pirate

nevermind.

suzielawrence

http://healthland.time.com/2013/07/19/news-genes-idd-in-obesity-how-much-of-weight-is-genetic/

The answer isn't yes or no. Yes, genetics can, and often do, cause people to be overweight or obese. Random mutations can cause that morning muffin to be either burned for fuel, or stored as fat. That being said, there are plenty overweight and obese people whose genetics do not predispose them to weight gain, they have gained weight solely through their own behavior. Oh, wait, much of our behavior is influenced heavily by genetics...

There are also cases like me out there - I was always thin until I got a pituitary tumor. The pituitary tumor has messed up my hormones so much that I have gained weight - all of it in my stomach. I look perpetually six months pregnant. I can lose weight, but only when I restrict to a level way beyond anything recommended here (or anywhere). So I keep trying, and failing, and trying again. I am surrounded by skinny people who live on pizza and beer, while I eat protein shakes and kale. Then go running.

If your point is that people shouldn't use genetics as an excuse to not make positive changes in their lives, then I completely agree with you. Even if I'll never look like I did before the tumor, I know that I feel better, physically and mentally, when I'm eating well and working out.

It sounds, however, like the real thesis of your paper is "Fat people are just lazy and should stop eating so much". If this is your stance, maybe you should spend some time examining your motivation for writing it. Because yes, some fat people are lazy and should just stop eating so much, but often, things are more complicated.

suzielawrence

http://healthland.time.com/2013/07/19/news-genes-idd-in-obesity-how-much-of-weight-is-genetic/

The answer isn't yes or no. Yes, genetics can, and often do, cause people to be overweight or obese. Random mutations can cause that morning muffin to be either burned for fuel, or stored as fat. That being said, there are plenty overweight and obese people whose genetics do not predispose them to weight gain, they have gained weight solely through their own behavior. Oh, wait, much of our behavior is influenced heavily by genetics...

There are also cases like me out there - I was always thin until I got a pituitary tumor. The pituitary tumor has messed up my hormones so much that I have gained weight - all of it in my stomach. I look perpetually six months pregnant. I can lose weight, but only when I restrict to a level way beyond anything recommended here (or anywhere). So I keep trying, and failing, and trying again. I am surrounded by skinny people who live on pizza and beer, while I eat protein shakes and kale. Then go running.

If your point is that people shouldn't use genetics as an excuse to not make positive changes in their lives, then I completely agree with you. Even if I'll never look like I did before the tumor, I know that I feel better, physically and mentally, when I'm eating well and working out.

It sounds, however, like the real thesis of your paper is "Fat people are just lazy and should stop eating so much". If this is your stance, maybe you should spend some time examining your motivation for writing it. Because yes, some fat people are lazy and should just stop eating so much, but often, things are more complicated.

jennk5309

Yes, I realize this is probably insulting.....It must have taken hours upon hours upon hours for Mrs. Ratfire to write so many posts. Perhaps sitting in front of the computer all day is a part of the problem??? I have a relative who swears she can eat only 500 calories a day and still weigh close to 400 pounds (nevermind that I grew up with her and know that she used to hide food and compulsively eat it in secret- and I have serious doubts that she changed that behavior). However, said relative literally sits all day on her couch and does nothing but surf the internet. Nothing. Tells her husband to feed the kids and clean the house and go to work.....

I don't care how little you eat, if you don't move, you're not likely to lose much weight.

_KitKat_

@MrsRatfire

At this point you are the one being rude, you are calling people names (2 wrongs don't make a right) and you are quoting me as if I backed up the statements you were making. I was disagreeing with the girl with a condition claiming she ate under what she burnt. The truth is the majority of people are fat because they made themselves that way. The rare few may have a condition that makes their TDEE extremely out side the curve that still does not mean they eat at a deficient, (for them they do NOT) they may eat at my deficient but not theirs. The odds that so many that come across this website have an extremely rare illness and then even have stats that are at the extreme end of their illness is unlikely. I am sorry but that is how it is. When I gained weight I was hoping my doctor found a reason, you know what she said: she said yea, you stopped being as active and increased portions and snacking; stop and you will go back to your normal self. It is a hard truth but since it normally takes 600 calories just to keep organs from dying I find it very unlikely that a human that is awake even with the most extreme medical condition is in a surplus at 1000 or 1200, the odds are astronomical for that to be the case and I am not a gambler. Health issues can make weight maintenance harder for some it can even lower their TDEE but it is still math. The other truth is if their are those that their TDEE is 800-1000 they truly are a miracle of evolution they are much more efficient at using available energy and will survive much better then most fit people if food was ever short and if they could eat less than they burn and still gain weight they would be an abundant resource for the creation of energy. They would scientific marvels that are the next step in human evolution.

Missjulesdid

Of course genetics plays a part in weight gain. It is not something that should be used as an excuse, but it's a FACT. For example, YES, your weight is determined by if you are eating at a deficit or a surplus, but the specific amount of calories required by the individual is determined by genetics. Also, stomach length is determined by genetics- a longer stomach requires more food to reach the level of satiety required to give us the "full signal". A propensity toward building muscle easily is genetic. Appetite and the production of appetite stimulating hormones is GENETIC... So while yes, obesity is the result of overeating according to your caloric requirements, there are genetic components that factor into WHY some individuals are more likely to eat more than their bodies require than others. Of course there are also mental, emotional and environmental factors as well.. but to say that genetics does not play a role is ridiculous.

Bottom line, many of us DO have our genetics stacked against us, we need to recognize it and gain control over it.

neandermagnon

People can be genetically predisposed to overeating through malfunction in the body's appetite regulation systems, i.e they never get the "full" signal when they've eaten enough so are prone to overeating. This can also happen due to damage to the hypothalamus, i.e it's not genetic it's environmental, but it still causes the person to have a tendency to overeat.

To some extent humans in general have a tendency to overeat, probably because Homo erectus didn't have a guaranteed food supply and thus people who overate when there was plenty of food and stored up fat for leaner times came through food shortages better and thus left more genes in the population. We're all the descendents of generation upon generation of people who survived food shortages - we're adapted for surviving in an environment where food was sometimes scarce and food always required effort (sometimes very strenuous effort) to acquire, not for living in a world where you can order pizza and mcdonalds over the telephone to be delivered through your living room window without even leaving the sofa. And if something is the result of natural selection, then it does come from genetics, because genes are what are passed from generation to generation and what natural selection acts upon. And when something comes from genes, there is nearly always variation. So there is definitely genetic variation in the extent to which people are predisposed to overeat. And that includes some people being predisposed to undereat - i.e. the "hard gainers" who do all kinds of weight lifting programmes and try their best to eat at a surplus but still don't gain weight because their appetite set point won't let them (and trying to eat more when you're full to the point of nausea is something no-one can do very easily).

This question is a highly complex one, and the issue of people thinking that they're the only one that finds fat loss difficult and that maintenance of a healthy weight requires effort and vigilance, or that being like this is abnormal and everyone else finds it easy, is not the same as the question as to whether some people are genetically predisposed to get fatter more easily than others.

However, going back to the OP's aim in this - whether someone's genetically predisposed to overeat more than average, that does not condemn them to a lifetime of obesity.... the obesity can be overcome through exercise and portion control (for someone prone to overeating, then exercise is probably even more important)........... the myth that "I have a genetic tendency to obesity therefore there's nothing I can do about being obese" is probably what needs to be challenged the most. Just because you're genetically predisposed to something doesn't mean it's impossible to mitigate that thing through controlling the environmental factors that interplay with the genetic factors. In the case of obesity that means ensuring an active lifestyle and good portion control.

I guess my definition may be a bit too black and white. The way I have looked at is, even if you have a medical condition, do you still have the ability to lose weight? If so, then it isn't a genetic issue, but rather environmental. To me environmental =/= genetic; I more see that as a variable. So I guess that question would be how the scientific community views genetic factors, which I would have to investigate more.

I view it this way because when I think genetics (eye color, skin color, bone structure, blood type) those are all things you cannot change (outside of surgery). And weight is something that can change.

yes, your definition is too black and white... many characteristics are the result of interplay between genetics and environment... take skin colour for example... you're born with skin a certain colour, and most people are born with an ability to tan when exposed to sunlight... so the actual colour is determined both by genetics and the environment (i.e. degree of exposure to sunlight). Even bone structure - malnutrition in childhood (e.g. rickets or calorie restriction) can change the size and shape of the skeleton. Lack of calories and/or protein in childhood can result in someone never reaching adult height, etc.

things you can't change frequently don't come from genetics... e.g. if someone loses a limb in an accident, they're stuck with 3 limbs for the rest of their life, that's not genetic but it's not something they can control. The degree to which someone can control something also often depends on genetics, for example I have very pale skin and freckles... I can tan very slightly but mostly my skin stays white, burns and has freckles.... however I know Mediterranean people who will be white in the winter and really dark in the summer if they choose to tan.

So skin colour is a good example of something that's genetic, yet some people can control it to a large degree through the environment and their choices (i.e. if they choose to sunbathe or cover up/use sunscreen)........ others like me have very little choice, and even though I can tan a tiny bit I choose not to because my skin's in the highest risk category for skin cancer and it's not worth it. Plus I like being pale. This example illustrates that just because someone has control over a particular characteristic it does not mean that characteristic isn't controlled by genes..... even the degree to which it can be controlled is genetic.....

re obesity - there are factors related to obesity that don't come from genetics, as in if you deprive anyone of food they will eventually starve to death and during that process they will stop being obese at some point.... and with a strict enough diet anyone can not be obese... but genetic factors are definitely at play as well... if you take a whole bunch of people and starve them they won't all die on the same day, some will survive longer in the food shortage than others... those that survive longer will probably also have a harder time fighting against obesity when not being starved, because their bodies are more predisposed to store fat and more predisposed to slow the metabolism in response to a food shortage... they may also have appetite regulatory systems that predispose them to eat more when they can eat... etc etc etc. and what gives someone an advantage in a food shortage gives them a disadvantage when on a diet to reduce body fat percentage... there are ways around it but ignoring the genetic factors and just assuming we're all the same in this respect isn't helpful, because if someone's finding something more difficult than average then acknowledgement of their struggle, together with tailored advice for how they can lose in spite of their difficulties is a lot better than just denying that they're struggling more than average. Note that in this paragraph I'm referring to normal variation in healthy people.... there are additional medical issues, some of them genetic some of them non genetic but akin to losing a limb in an accident, which can make it a whole lot harder again to maintain a healthy body composition.

JessG11

Genetics does not determine your weight. What genetics can affect is: muscle and bone structure, blood pressure, medical issues, cholesterol.

THIS....for example, thyroid issues run in my family. I don't believe it has caused me to gain weight, but before I was diagnosed and put on medicine, I worked out hard with a trainer and ate well. However, my metabolism was barely functioning. That's genetic for me. Other people have genetic issues/diseases that may cause weight gain/hard to lose. There are also mental health disorders that are genetic that could lead to behaviors that drastically increase/decrease weight.