November 5th, 2007
Is starvation mode a myth?- No! It’s very real and here is the proof
Just this morning, I received two separate emails where Burn The Fat readers had been told by other fitness experts that what I’ve been teaching for years about starvation mode and being cautious about very low calorie diets is wrong. I’ve reprinted one of them below with my answer – including all the scientific proof you need. Starvation mode is a real phenomenon. Apparently even some fitness professionals don’t have all the facts and are attempting to debunk myths when instead they may be perpetuating them.
NOTE: Our ‘sure things for fat loss’ series will continue in the next issue of the burn the fat newsletter, but today I wanted to cover the topic of “starvation mode” because it has come to my attention that a number of fitness professionals are claiming that starvation mode is a myth and does not exist.
Starvation mode exists and there is plenty of science to prove it.
This article below is a bit scientific, but I urge you to invest the time to read it.
Sincerely,
Tom Venuto,
IS STARVATION MODE A MYTH? NO! STARVATION MODE IS VERY REAL AND HERE’S THE SCIENTIFIC PROOF
QUESTION:
Tom, I was wondering if you had seen the 6 part e-mail series sent out by [name deleted] from [website deleted]. if you look at the last part, he basically states that “starvation mode” is a bunch ofcrap made up in order to sell diet programs. He didn’tmention you, but it almost sounds like he’s talking about youspecifically. How do you feel about this?
ANSWER:
Yes, I saw that article/email and the author is mistaken about starvation mode. In his article, he accused those of us who use the term “starvation mode” as beingunscientific and he even says “dont buy diet books if they mention the starvation mode.” I’ll make it clear in a moment, that in this case, he is the one who doesn’t appear very well read in the scientific literature on the effects of starvation and low calorie diets.
I do have to point out first that the effects of starvation mode are indeed sometimes overblown. There are also myths about the starvation mode, like it will completely”shut down” your metabolism (doesn’t happen), or that if you miss one meal your metabolismwill crash (doesn’t happen that fast, although your blood sugarand energy levels may dip and hunger may rise).
Another myth about starvation mode is that adaptive reduction inmetabolic rate (where metabolism slows down in response to decreasecalorie intake) is enough to cause a plateau. That is also not true.it will cause a SLOW DOWN in progress but not a total cessation offat loss.
As a result of these myths, I have even clarified and refined myown messages about starvation mode in the past few years because Idon’t want to see people panic merely because they miss a meal or they’re using anaggressive caloric deficit at times. I find that people tend toworry about this far too much.
However, starvation response is real, it is extremely well documentedand is not just a metabolic adaptation – it is also a series ofchanges in the brain, mediated by the hypothalamus as well as hormonalchanges which induce food seeking behaviors.
Here is just a handful of the research and the explanations thatI have handy:
Ancel Key’s Minnesota starvation study is the classic work in this area, which dates back to 1950 and is still referenced to this day. In this study, there was a 40% decrease in metabolism due to 6 months of “semi-starvation” at 50% deficit.
Much or most of the decrease was due to loss of body mass, (whichwas much more pronounced because the subjects were not weighttraining), but not all of the metabolic decline could be explainedsimply by the loss of body weight, thus “metabolic adaptation” tostarvation was proposed as the explanation for the difference.
Abdul Dulloo of the University of Geneva did a series of studies that revisited the 1300 pagesof data that keys collected from this landmark study, which willnot ever be repeated due to ethical considerations. (it’s not easyto do longitudinal studies that starve people, as you can imagine)
Here’s one of those follow up studies:
“Adaptive reduction in basal metabolic rate in response tofood deprivation in humans: a role for feedback signalsfrom fat stores. Dulloo, Jaquet 1998. American journalof clinical nutrition.
Quote:
“It is well established from longitudinal studies of humanstarvation and semistarvation that weight loss is accompaniedby a decrease in basal metabolicrate (BMR) greater than can beaccounted for by the change in body weight or body composition”
“the survival value of such an energy-regulatory process thatlimits tissue depletion during food scarcity is obvious.”
Also, starvation mode is a series of intense food seeking behaviors and other psychological symptoms and if you do any research on the minnesota study and other morerecent studies, you will find out that starvation mode as a spontaneousincrease in food seeking behavior is very, very real.
Do you think sex is the most primal urge? Think again! Hunger is the most primal of all human urges and when starved, interest in everything else including reproduction, falls by thewayside until you have been re-fed.
There are even changes in the reproductive system linked tostarvation mode: It makes total sense too because if you cannotfeed yourself, how can you have offspring and feed them – when youstarve and or when body fat drops to extremely low levels, testosterone decreases in men, and menstrual cycle stopsin women.
Starvation mode is not just adaptive reduction metabolicrate – it is much more.
There IS a controversy over how much of the decrease in metabolismwith weight loss is caused by starvation mode, but the case isextremely strong:
For example, this study DIRECTLY addresses the controversy overHOW MUCH of a decrease in metabolism really occurs with starvationdue to adaptive thermogenesis and how much is very simply due to aloss in total body mass.
Doucet, et al 2001. British journal of nutrition. “Evidence for theexistence of adaptive thermogenesis during weight loss.”
quote:
“It should be expected that the decrease in resting energyexpenditure that occurs during weightloss would be proportionalto the decrease in body substance. However, in the caseof underfeeding studies, acute energy restriction can also leadto reductions in resting energy expenditure which are notentirely explained by changes in body composition.”
Starvation response is even a scientific term that is used in obesity science textbooks – word for word – CONTRARY to the claimmade by the expert mentioned earlier who thinks the phrase, starvationmode is “unscientific.”
Handbook of Obesity Treatment, by wadden and stunkard
(two of the top obesity scientists and researchers in the world )
quote:
“The starvation response – which is an increase in food seekingbehavior – is most likely mediated by the decrease in leptinassociated with caloric deprivation.”
Textbooks on nutritional biochemistry also acknowledge the decrease in metabolism and distinguish it as an adaptive mechanism, distinct from the decrease in energy expenditure that would be expected with weight loss. In this case, the author also mentions another downside of very low calorie diets: spontaneous reduction in physical activity.
Biochemical And Physiological Aspects of Human Nutrition by SM. Stipanauk, professor of nutritional sciences, Cornell University (WB Saunders company, 2000)
Quote:
“During food restriction, thermic effect of food and energy expenditure decrease, as would be expected from reduced food intake and a reduction in total body mass. Resting metabolic rate, however declines more rapidly than would be expected from the loss of body mass and from the decline in spontaneous physical activity due to general fatigue.
This adaptive reduction in resting metabolic rate may be a defense against further loss of body energy stores.”
Granted, it is more often referred to as “metabolic adaptation”or “adaptive reduction in metabolic rate.” However, starvationmode and starvation response are both terms found in the scientificliterature, and they are more easily understood by the layperson,which is why I choose to use them.
Another effect of starvation mode is what happens after the diet:A sustained increase in appetite and a sustained reduction ofmetabolic rate that persists after the diet is over. Although controversial, this too isdocumented in the literature:
American Journal clinical nutrition 1997. Dulloo “post starvationhyperphagia and body fat overshooting in humans.”
American Journal Clin Nutrition 1989, Elliot et al. “Sustaineddepression of the resting metabolic rate after massive weight loss”
quote:
“Resting metabolic rate of our obese subjects remaineddepressed after massive weight loss despite increased caloricconsumption to a level that allowed body weight stabilization.”
and Dulloo 1998:
“The reduction in thermogenesis during semistarvation persistsafter 12 weeks of restricted refeeding, with its size being inverselyproportional to the degree of fat recovery but unrelated to thedegree of fat free mass recovery.”
By the way, this explains what some people refer to as “metabolicdamage” and although this is not a scientific phrase, you cansee that it too is a reality. It is the lag time between whena diet ends and when your metabolism and appetite regulating mechanisms get back to normal.
Last, but certainly not least, and perhaps the best indicator ofstarvation mode is the hormone LEPTIN. you could spendweeks studying leptin and still not cover all the data that hasbeen amassed on this subject.
Leptin IS the anti starvation hormone. Some people say leptinIS the starvation mode itself because it regulates many of thenegative effects that occur during starvation.
leptin is secreted mostly from fat cells and it signals yourbrain about your fat stores. If your fat stores diminish (dangerof starvation), your leptin decreases. If your calorie intakedecreases, your leptin level decreases.
When leptin decreases, it essentially sounds the starvation alarm.In response, your brain (hypothalamus) sends out signals forother hormones to be released which decrease metabolic rateand increase appetite.
In summary and conclusion:
There is no debate whatsoever about the existence of starvation mode – IT EXISTS and is well documented.
There is also no debate whatsoever that metabolic rate decreaseswith weight loss. It happens and is well documented, and it isa reason for plateuas.
There’s really only ONE debate about starvation mode that is –HOW MUCH of the starvation mode is comprised of adaptivereduction in metabolic rate and how much is due to loss oftotal body mass and increased feeding behaviors?
Researchers are still debating these questions, in fact justearlier this year another study was releasd by Major and Doucetin the international journal of obesity called, “clinicalsignificance of adaptive thermogenesis.”
Here’s a quote from this latest (2007) study:
“Adaptive thermogenesis is described as the decrease in energyexpenditure beyond what could be predicted from the changes infat mass or fat free mass under conditions of standardized physicalactivity in response to a decreased energy intake, and couldrepresent in some individuals another factor that impedes weightloss and compromises the maintenance of a reduced body weight.”
I respect the work that other fitness professionals are tryingto do to debunk diet and fitness myths, but this fellow didn’t seem to do his homework andtotally missed the boat on this article about starvation mode.
What’s really odd is that he didn’t quote a single study in his article, despite his repeated reference to “scientific research.”
If he wanted to argue against adaptive reduction in metabolicrate and chalk starvation mode up purely to increase in food seekingbehaviors… and if he wanted to attribute the decreased metabolismwith weight loss purely to lost body mass, he easily could havedone that. But he didn’t cite ANY studies. He just expects us to take his wordfor it that “starvation mode is a myth,” and people like me who use the phrase starvation mode are “unscientific”
Either way you argue it – and whatever you choose to call it – “starvation response” is a scientific fact and that’s why prolonged low calorie diets are risky business and mostly just quick fixes.
The rapid weight loss in the beginning is an illusion: Starvation diets catch up with you eventually… just like other habits such as smoking appear to do no harm at first, but sooner or later the damage is done.
For years I’ve considered it so important to understand theconsequences of starvation diets that my entire burn the fat program is built around helping you recover from metabolic damage from pastdiet mistakes, to avoid the starvation mode, or to at leastkeep the effects of the starvation mode to a minimum so you canlose the fat and keep the muscle.
Sincerely,
Your friend and “Burn The fat coach”
Tom Venuto, CSCS, NSCA-CPT
www.BurnTheFat.com
PS. For more information on getting lean without starving yourself orharming your metabolism, visit my website at www.BurnTheFat.com.
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