Starvation Mode Myths and Science

Interesting topic
Thank you

There is also some research that suggests that someone who is, say, 35%+ body fat reacts differently to a low-calorie eating plan than someone who is 20%-25%. IMO, someone who is obese should not be concerned with "starvation mode" while following a low-calorie (by that I mean 1000-1200 Cal/day) intake plan. Even in instances where BMR does decrease, it goes back up again once the person increases caloric intake.

I think it is important to realize that weight loss is a process that can require different interventions at different stages; and also that it is a complex issue that includes many variables. People should be very wary about repeating cliches and making "absolutist" statements (unfortunately, few of the people who make those kinds of statements would ever read this topic or get this far on the comment list).

Overall, I was impressed by most of the comments in this thread--a lot of good thinking.

Thanks for at least backing up your post with some science. I think that is one of maybe 3 posts on here that I've seen actually containing a citation that hasn't been from Banks or Songbyrd.

However there is one part that appears to be missing from your analysis (and it is brushed on in some of the other posts). If the human body is deprived of any nutrient necessary for something it will make up the difference by taking it from whatever source is readily available that needs it 'less'. For instance, the liver can be broken down to provide iron, bones to provide calcium and phosphorous, etc. When people intensely restrict their diets, even for a few days, this deficit in other vitamins and minerals has to be supplied from the body. Now the amount pulled in a day or two is nothing that would really be out of the ordinary for catabolic reactions. However if this begins to happen frequently, or for longer stretches of time there could be some pretty bad issues, including permanent damage to the heart and other organs.

As someone who does Fasting throughout the year (religious purposes), I appreciate this information! I have read it somewhere before, because of course you want to be educated when you do Fast.

But having had to battle this weight loss issue, in large due to medical issues and medications, I know that I have had days when I was just simply not hungry. Today being one of those days. My point? I have ALWAYS lost weight. I have never Fasted or eaten well below my suggested daily caloric levels and not lost weight.

Prior to my medical issues, I was extremely active; and had a very "functional" metabolism. In fact, my docs tell me that it is because my being so active prior, it is partly the reason I can still do quite a bit comparably to someone with same conditions who was not as active; which equals ability to lose the weight. Metabolism is a funny thing and it is not a ONE SIZE fits all topic.

But this posting helps to despel some of the falsehoods being thrown out to us.

This was a very informative post. Thanks, again, for sharing with all of us!

Oh, and I agree that the whole one or two days of eating well below your caloric target does not induce "starvation mode". Kinda silly.

Almost as silly as "muscle weighs more than fat". A pound of muscle and a pound of fat both weigh. . . .a pound!

It's denser. Of course a pound weighs as much as a pound, but a cubic inch of muscle weighs more than a cubic inch of fat because muscle is denser.

Thanks so much for the post, it is good to see your perspective. :drinker: :drinker:

I wish it were easier to find peer reviewed research, but most peer reviewed stuff requires subscriptions:sad: . That relegates most of us from surface level information. :grumble: For instance, http://www.shapefit.com/basal-metabolic-rate.html has the following to say about BMR and starvation mode: "It is well known that cutting calories too much slows down the metabolic rate, decreases thyroid output and causes loss of lean mass, so the question is how much of a deficit do you need?" That is not original research, but perhaps a 3rd or 4th generation retelling of original research.

If you go for information "closer" to the original research, you can keep digging further. A textbook on Anatomy and Physiology has the following to say ( http://www.mhhe.com/biosci/ap/vdgconcepts/digestive/reading5.mhtml ), "No matter what the cause, starvation takes about the same course and consists of three phases. The events of the first two phases occur even during relatively short periods of fasting or dieting, but the third phase occurs only in prolonged starvation and can end in death. "

If you go to the "experts" (American College of Sports Medicine) you will find the following ( http://www.acsm.org/AM/Template.cfm?Section=Search&SECTION=20044&TEMPLATE=/CM/ContentDisplay.cfm&CONTENTID=1259 ), "Lastly, starving
the body of food and nutrients will slow appropriate energy systems down to a halt in order to preserve enough energy for survival thereby decreasing caloric expenditure, substantially." I read this to mean it will lower the BMR (since TDEE is BMR x activity level multiplier).

So, you have conflicting information from different sources.:noway: I think you will find that happens in every field, which is exactly why scientific journals exist in the first place. So, all we can do, as laymen, is try our best to work out what makes the most sense. :huh:

Here is where I think we are in complete agreement. :happy: IMO starvation mode will not begin in a number of hours. IMO I will not go into starvation mode simply because I didn't eat my exercise calories.

Here is where I think we differ in opinions. IMO starvation begins in only a few hours after eating, when the liver runs out of glycogen, which it breaks down into glucose. At that point the body must start looking for other sources of energy. IMO starvation ultimately causes your BMR to decrease. I believe this to be measured in weeks rather than months. IMO you should never (unless under expert care/supervision) establish your caloric goal more than 20% below your BMR.

I have been wrestling with the whole exercise calorie/starvation problem for many weeks now.:huh: :huh: I have been reading a bunch trying to come to terms with issues I see in both sides of the debate. I am sitting pretty squarely in the middle ground.

Speaking more to the point, I believe that we live in an instant gratification society (Lord please grant me patience... right now ). As such, all too frequently, I see someone who has 10 - 20 lbs to lose, and when you reverse engineer their numbers, you discover that they are probably setting a goal of 2 lbs per week. That is unrealistic, it puts their caloric intake well below their BMR. These are typically the same people who have complained about not losing weight for 3-4 weeks. So, this means that they have been depriving their bodies of nutrients, not for a few hours, but for several weeks. :sad:

When I read a case as above, I go to the numbers. There are usually enough numbers on a person's profile to get a rough picture of where they are at. For instance, I saw a case of a 25 y.o. male, who weighed in excess of 225 lbs. When I "assumed" a height of 5'10", his BMR was around 2000 calories. When I "assumed" a lightly active lifestyle, his TDEE was in excess of 2760 calories. He said he was eating 1200 calories (and I won't mention the 3-4 times a week he said he was working out). That worked out to a 3 lb per week goal. I suggested he drop his goal to 1-1.5 lbs per week. That would bring his daily calorie goal to right at or above his BMR, yet still provide him with a healthy & sustainable weight loss track.

In the cases where there isn't enough information, but I have a suspicion, I ask the person to go look at their numbers and see if my suspicion bears out. In that case they should try to adjust their goal downward. But again, it is only after someone states they have been stuck for several weeks.

I also believe that every member of MFP should care enough about their well being to check out what anyone says. After all, with some exceptions, none of us are fitness experts. And from what I gather, even the fitness experts disagree on the exercise calorie/starvation mode issues. You know... when someone says, "I read on the internet..." :embarassed:

Simple fact of the matter is that most of us are here because we didn't know enough about nutrition and fitness. Most of us are on a journey, some of us on a longer journey than others. I have a total of 105 lbs from starting weight to goal weight. I need to look at the long term journey, so I am trying to understand how and why my body will lose weight on the MFP plan.

This was an awesome post and I thank you for it.

i do however caution everyone to realize that every BODY is different.

I have some pretty bad thyroid issues thanks to genetics and have been advised by doctors (note the plural s there) that if I consume more than 1,100 calories a day without an external metabolism stimulant (i.e. thyroid pills), I will gain weight. i only loose at 1,000 calories or less day - even when I was on my medication. I maintain on 1,200 a day (approx) and i gain above that.

So to anyone providing advice here I just caution you to remember that there are significantly different circumstances for different people....

Saving to my list for reading later.

This "argument" and the low-carb vs high carb debate are the reasons I stay off the forums, mostly and use MFP for logging calorie burn and food intake.

Sometimes information overload occurs. Sigh.

Bump for later :flowerforyou:

bump

Very interesting and well researched information, thanks for posting! One thing that I can't get out of my head is this "A few even mutilated themselves, one chopping off three fingers in stress" What doctor allowed this to occur? I can't imagine how this helped the research.

Bump!

a well written post... thank you.

I am not one of the "starvation mode nazis" but I do encourage people to eat their exercise calories. The reason I do is not because I think they will go into starvation mode in just a few days, but in order to influence them towards healthier habits overall. Of course it's fine to be a little over or under, and fluctuate your calories as each day is unique.

But if someone is under the impression that eating back their exercise calories is "defeating the purpose of exercise" (have seen this comment hundreds of times), and has plans to go to the gym every day and work off hundreds of calories, and yet still stick to the 1200 plan regardless of activity level, I do think it's helpful for them to know that doing that may suppress their metabolism over time. So I encourage them to eat back their exercise calories, and I always post the link to the very helpful thread "confused about eating your exercise calories" or the "700 calories a day and not losing".

cheers!:drinker:

Greatttttt and really informative post! Thanks so much for all that info Fit4Europe.... i do have one question; you mentioned that for the MN study, the participants were told to walk 22 miles a week.... but walking is more cardiovascular exercise, right? (sorry i'm not really that knowledgeable in exercise department lol)

To your knowledge, will carrying out strength training/muscle building activities prevent the loss of muscle tissue? And due to the either the maintenance of the muscles mass (or potential increase), will the metabolism not drop as much as the amount of work being carried out is the same? Did any of the studies explore this?

Thanks again!