Starvation Mode is a Myth: The Science

maybe we should better define "low calorie diet"? I know we're debating abotu the whole 1200 mark and all... are we talking about 600 calories a day or 950-1000?

and this is assuming a person is set at 1200 calories by MFP - not 2,500 or 1850 or ... whatever. Cuz really, I don't think anyone that's posted is interested in a 600 calorie intake. It would seem to be that the debate is rating over a 200 calorie margin of error.

200 calories. That is 3 cookies & a cup of coffee; that is a 1/3 an avacado (or something like that); a handful of chips or crackers; a tablespoon of pasta, a yogurt & apple.... in short, it's missing 1 snack.

Just to add another perspective. I think some are assuming people are referring to a major cut in dietary needs and I don't think that's the case. We're not talking extremes such as some of the studies are citing. We're talking about day to day people with *some* activity and who generally make decent food choices through the day. It seems to me people are thinking that those who miss that one snack are going to dry up and wither away.

The other thing I'd like to ask is where does the concern come from? Is it because you want to be right or is it genuine concern for the wellbeing of others? Some responses look to be genuine concern - which is really kind. Many are offering responses that give the appearance of more the need to be right...which is fine too, but doesn't do much as far as getting people on the other side of the fence on board with your idea.

Maybe more questions should be asked rather than demands for a change of mind/heart? I did see some posts that indicated some people obviously have a scientific background - but really, the jargon isn't helpful. Put things in laymen's terms and we have to admit, science is NOT the end all be all. I mean.. Pluto. Really? Need I say more? It's a generalization and we must be careful of that as well. We need to all learn a little flexibility in our thinking and the way we approach debate.

I firmly agree that the 1200 calorie thing has nothing to do with the OP's point. Starvation mode is intimately tied to a person's TDEE (maintenance calories) and can usually be defined by the long term (>3 days) reduction of calories to a point that is below the threshold where that particular person can replenish glycogen stores in the liver and muscle.

In layman's terms, starvation mode is a relative condition to the person you are describing, thus everyone is different. A host of genetic, environmental, and internal factors decide when a body will cross the threshold.

Starvation mode begins when the body can not reach energy metabolism homeostasis (I.E. energy needed is exactly equal to energy provided). This means carbohydrates consumed, plus the result of lipolysis plus the result of gluconeogenesis (protein break down for energy), plus the existing glycogen stores can no longer reach an equallibrium with what the body demands for energy.

So, this all said, someone who is obese, has a lot more lipids (fat) in their body to use to make up the large deficits. when someone who is NOT so big tries to do the same thing, the gap between TDEE and the starvation mode threshold is far smaller, which is why you can't lose as much weight if you only have 20% body fat as you can if you have 35% body fat, and why more of that weight will be lean tissue (protein from muscle tissue and other non-fat substrates)

the discussion in the medical community isn't whether any of what I just wrote is true, the discussion is more along the lines of what the long term effects of starvation mode are to the body, and what hormones are triggered in response to it, and what this does to body composition after those hormone changes go into affect. THAT is where the medical community has debates.

For instance, there's a strong push to find out the role of Growth Hormone and Testosterone in a fasting environment, along with the "fat" hormones like cortisol (which is called the fat hormone because it's produced by adipocites, or fat cells in higher amounts as a response to times of high stress), and other hormones which are catalysts for energy absorption into cells like insulin. While we have a basic idea of how these hormones interact, because of the amount of chemicals in the body, their VERY complex interactions, and the changes that occur during different times (high stress, underfeeding, obesity, anorexia...etc) we don't know exactly what role these hormones play yet. But we are coming closer every day.


You asked where the concern comes from. Well I admit, I'm no longer trying to lose weight, and could have stopped using MFP years ago. But I'm intimately tied to weight issues by family, I was formerly obese, I'm now a personal trainer, and I genuinely like helping others and receive a certain amount of personal joy from it. My science background allows me to read technical journals and research and be able to (hopefully) translate it into useful information.

You say the technical jargon isn't helpful. but I disagree. Besides the small percentage of people that can actually read and correctly interpret the studies (they're difficult sometimes), there are a lot of people here that need to know that we who cite these resources are actually doing real investigation into the issues, and even if you can't read them all, the fact that we cite them and show how we arrived at a conclusion is important to the process.

As to the concept that science isn't the end all. I disagree, citing Pluto as an example isn't really very relevant as that wasn't a "mistake" it was a reclassification based on additional information. Any mistakes that we make in science are because we are imperfect, not because the science itself is wrong, our existence in the physical world has laws, our bodies follow those laws, just because we don't understand them all yet, and get them wrong sometimes, doesn't make the laws wrong, it makes us flawed as beings.

I have a lot more I would love to say, but I've already written to much. There's reams and reams of data out there if you want it. And there's opinions aplenty on this topic, believe what you want for what ever reasons you want, that won't change the truth, I just hope those out there in MFP land that are unsure do some analytics on the posts they read and don't choose things based on "how much they like the poster" or how much weight the poster has lost, because there's a lot more to this site than a popularity contest.

Yes It is a myth!. Thanks for proclaiming the truth in open!

1200 calories is the absolute minimum amount necessary for the body to function. Of course, it will vardepending on the person, but if one eats below 1200, they can get seriously ill in a short period of time.

Starvation mode refers to a prolonged period of time that a body is denied the nutrients necessary for its survival. Just because you fast for a day, doesn't mean your body will enter starvation mode. I try to fast every month, having a 1-day water-only fast. This does not mean that my body enters starvation mode, and I don't think MFP or any personal trainer or nutritionist will disagree.

hmmmm...I stay under 1200 calories every day, exercise every day, and my health has done nothing but improve

Anybody find it funny that the people with the most lbs lost are they ones who can see that the article presented makes sense. It is the ones with low lbs lost that seem to want to continue to believe in Starvation Mode.

yes I agree this does not make you an expert. I am down 70 lbs, I an no expert but have read a few great nutrition books and personal trading texts as well. I believe the body needs a very important amount of vitamis,.minerals, proteins, carbs, fats and much more that a huge calorie deficit will not give you. I think going way under now and then is no big deal and can help wil weight loss but if you want your body to have the right things it needs to have full antibodies, recovery chemicals and such that come only for food and are not reproduced by the body itself, enough food is needed. This does not mean 1200 is the minimum for everyone., as stated many times, everyone is different. This means everyone should ensure that they are not deficient in any crucial needs before hacking calories soooo low. This is a life change and weight loss is meant to be forever. We should do it in a way that we can continue for a lifetime to stay healthy. We all have different struggles but remember your body is the only one, no marr how ya do it, make sure it has what it needs.

1200 calories is the absolute minimum amount necessary for the body to function. Of course, it will vardepending on the person, but if one eats below 1200, they can get seriously ill in a short period of time.

Starvation mode refers to a prolonged period of time that a body is denied the nutrients necessary for its survival. Just because you fast for a day, doesn't mean your body will enter starvation mode. I try to fast every month, having a 1-day water-only fast. This does not mean that my body enters starvation mode, and I don't think MFP or any personal trainer or nutritionist will disagree.

hmmmm...I stay under 1200 calories every day, exercise every day, and my health has done nothing but improve

Anybody find it funny that the people with the most lbs lost are they ones who can see that the article presented makes sense. It is the ones with low lbs lost that seem to want to continue to believe in Starvation Mode.

Some how the starving kids in the world seem to not be able to gain any weight by making sure they eat their 1200+ calories a day..?