The Minnesota Starvation Experiment

momof2winsplus

It is one of the oldest scientific experiments on starvation (1/2 calories). Some amazing results that echo so many failed diets!

In 1944, Two hundred conscientious objectors volunteered, as an alternative to war, and Keys and his team of researchers whittled these down to 36 men. The men (all aged 20-33) were chosen for their physical and mental resilience. The results, 1,385 pages in total, were published in “The Biology of Human Starvation” (1950).

The year long experiment was split into four phases:
1) The Control Period (12 weeks): The key goal of this period was to determine the calorie requirement for the men. It was established that the men maintained their weight at approximately 3,210 calories a day whilst walking 22 miles each week – an average of just three miles a day (45-60 minutes walking).

2) The Starvation Period (24 weeks): The fact that the study was referred to as a “starvation experiment” is so interesting, because the six-month ‘starvation’ was actually a calorie controlled diet of approximately 1,600 calories per day (more calories than many modern diets allow). The meals were made up of foods typically available in Europe during the latter stages of the war: potatoes, turnips, bread and macaroni – i.e. starchy carbohydrates. Ancel Keys set out to try to induce a 25% weight loss in each man in 24 weeks.

3) Restricted Rehabilitation Period (12 weeks): The men were divided into four groups of eight (four had been dismissed for stealing food and binging) and given different calorie, protein and vitamin levels to see what would best re-nourish them back to health.

4) Unrestricted Rehabilitation Period (8 weeks): For the final period, the men could eat as much as they wanted and the research team carefully recorded what they did in fact eat.

This invaluable study tells us the following about dieting and weight loss:

1) Physically, the men reported incessant hunger, weakness, exhaustion and they lost 21% of their strength in the first 12 weeks alone. They experienced dizziness, muscle wasting, hair loss and reduced coordination. Several withdrew from their university classes, because they simply didn’t have the energy or motivation to attend.

2) You may have heard of the saying “To lose 1lb of fat you need to create a deficit of 3,500 calories.” The Minnesota experiment alone renders this statement invalid.

The deficit, in Keys’ study, started off at 1,640 calories a day. Assuming that the deficit remained at 1,640 for the 24 week ‘starvation’ period, if the 3,500 formula were correct, during the 24 weeks, every man should have lost at least 78 pounds in fat alone and more on top of this in water and lean tissue. The average weight loss of the men was less than half of this – 37 pounds – 1.5 pounds per week. If the 3,500 formula were correct, the lightest man in the study, Bob Villwock from Ohio, should have finished the study below three stone (he would, of course, have died long before this).

3) The less you eat, the less you must continue to eat to have any chance of losing more weight and weight loss will stop, at some point, whether you like it or not.

As Keys showed, the men needed 3,200 calories, on average, to maintain their weight. As the men were given 1,570 calories a day in the ‘starvation period’, they lost weight and their energy need fell and therefore the calorie level needed to fall, to maintain the deficit.

Interestingly, Keys rejected the 3,500 formula from the outset and relied instead on adjusting the calorie intake every week to try to induce his desired weight loss of 25%. Keys found he needed to limit some men to 1,000 calories a day to try to induce further weight loss (the men should have been losing over 5lbs per week, at this calorie intake, having created a deficit of almost 2,500 calories a day from their original calorie need. In reality the body had adjusted energy need to resist any further weight loss).

All reached a plateau around week 20 and further weight loss could not be induced. At least one diary recorded weight gain in the final month of the ‘starvation’ period.

4) The body will do whatever it takes to reverse the effects of starvation/dieting.

During the restricted rehabilitation period, the four different groups of men were given 400, 800, 1,200 or 1,600 additional calories per day. Within each group of eight men, some were also given additional vitamin and protein supplements. Ancel Keys concluded that the only thing that determined the speed at which the men recovered was the calorie intake. The body didn’t respond to vitamins or protein – it just wanted the energy (calorie) deficit to be reversed.

It can be no surprise; therefore, that when given free access to food, in the final two months, the men overate and binged to correct the calorie deficit they had suffered. One man managed to eat 11,500 calories in one day and men still felt hungry consuming twice the number of calories that maintained their weight in the control period. They all gained all their weight back and approximately 10% more than they weighed before the experiment. Men who had previously shown no awareness of body size and image reported ‘feeling fat’.

http://www.zoeharcombe.com/2009/12/the-minnesota-starvation-experiment/

fittiephd

Hm that's really interesting. Also shows the mentality of the time..

mandiemma

Wow, that's quite the read! Thanks for the share :-)

cjw6

Important to note that the study started off with people who were a normal healthy weight. The bodies of people with substantial excess weight would respond differently.

StarryEyed500

3) The less you eat, the less you must continue to eat to have any chance of losing more weight and weight loss will stop, at some point, whether you like it or not.

Interesting. No wonder so many "plateau".

mastone99

Wow...

Vailery

Seems like you wouldn't be very healthy only eating starchy carbs no matter how many calories you ate..

rbbrrmqn

Thanks so much for posting this!!!!!

MinimalistShoeAddict

Important to note that the study started off with people who were a normal healthy weight. The bodies of people with substantial excess weight would respond differently.

This is an extremely important distinction. The MN study was unique because the WW2 conscientious objector "volunteers" were all lean to begin with. Naturally their fuel source (body fat) would become depleted much faster than those who were morbidly obese. This was by design.

Here is a picture of someone from the study:



Minnesota Starvation Experiment:
http://jn.nutrition.org/content/135/6/1347.full

"The Minnesota Starvation Experiment, as it was later known, was a grueling study meant to gain insight into the physical and psychological effects of semistarvation and the problem of refeeding civilians who had been starved during the war."

Here is an extreme example of how different the results of a "starvation" diet was for someone who was morbidly obese to begin with (27 year old male with a starting weight of 456 pounds):

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2495396/pdf/postmedj00315-0056.pdf

The key takeaway here is that a VLCD has a vastly different impact on lean/underweight individuals than it does on obese individuals. All of these studies were closely controlled and and under doctor supervision.

Mr_Knight

The conclusion is that an average height male can get his body to maintenance level of 1600 calories, and by the time they do, the body will be extremely extremely lean. Considering the BMR of a 150 pound skinny male is already under 1600, that isn't much of a revelation.

To say that further weight loss could not be induced is incorrect - if calories had been dropped more, more weight would have been lost.

There was an extended "experiment" in starvation diets during WW2. It was called a concentration camp, where the caloric intake averaged approximately 800 calories/day. Unfortunately, nobody plateaued, they just kept losing weight until they died or where rescued.

The key takeaway here is that a VLCD has a vastly different impact on lean/underweight individuals that it does on obese individuals.

I'm baffled why this distinction is so hard for so many to grasp.

gigglesinthesun

2) You may have heard of the saying “To lose 1lb of fat you need to create a deficit of 3,500 calories.” The Minnesota experiment alone renders this statement invalid.

The deficit, in Keys’ study, started off at 1,640 calories a day. Assuming that the deficit remained at 1,640 for the 24 week ‘starvation’ period, if the 3,500 formula were correct, during the 24 weeks, every man should have lost at least 78 pounds in fat alone and more on top of this in water and lean tissue. The average weight loss of the men was less than half of this – 37 pounds – 1.5 pounds per week. If the 3,500 formula were correct, the lightest man in the study, Bob Villwock from Ohio, should have finished the study below three stone (he would, of course, have died long before this).

3) The less you eat, the less you must continue to eat to have any chance of losing more weight and weight loss will stop, at some point, whether you like it or not.

As Keys showed, the men needed 3,200 calories, on average, to maintain their weight. As the men were given 1,570 calories a day in the ‘starvation period’, they lost weight and their energy need fell and therefore the calorie level needed to fall, to maintain the deficit.

Interestingly, Keys rejected the 3,500 formula from the outset and relied instead on adjusting the calorie intake every week to try to induce his desired weight loss of 25%. Keys found he needed to limit some men to 1,000 calories a day to try to induce further weight loss (the men should have been losing over 5lbs per week, at this calorie intake, having created a deficit of almost 2,500 calories a day from their original calorie need. In reality the body had adjusted energy need to resist any further weight loss).

All reached a plateau around week 20 and further weight loss could not be induced. At least one diary recorded weight gain in the final month of the ‘starvation’ period.

is it truly rendered invalid though? These men were not obese or even overweight to begin with so it leaves to reason that they simply got to the stage when they couldn't lose anymore weight, because they were very underweight and had little body fat and probably very little LBM left. There are anorexics out there that gain on very little calories, but that does not necessarily apply to overweight individual.

It does not prove that plateaus are inevitable, it merely shows that when you have nothing left to lose you don't continue to lose until you drop dead. As the pictures of the men showed when they got to the stage that they stopped losing it was unequivocally clear that they were very underweight. It does not indicate that overweight/obese individuals, who restricted their calories for a 24 week period, would inevitably plateau from week 20 onwards. In fact the countless success stories on this site of people losing significant body weight over a period of 12-24 months could serve as proof perhaps that this is not the case.

Mr_Knight

is it truly rendered invalid though? These men were not obese or even overweight to begin with so it leaves to reason that they simply got to the stage when they couldn't lose anymore weight, because they were very underweight and had little body fat and probably very little LBM left.

Right. The crucial point here is what did NOT happen - their BMR/TDEE did not shrink to that low level until they had achieved a ridiculous level of leanness.

IE, they didn't stall on weight loss until they were long past the point of needing weight loss.

(I'm not suggesting you disagree with this, just highlighting it because so many on MFP truly do not get it - and need to)

lisabinco

3) The less you eat, the less you must continue to eat to have any chance of losing more weight and weight loss will stop, at some point, whether you like it or not.

Interesting. No wonder so many "plateau".

Good read. Thanks for posting. I wouldn't have any energy either on such a poor, starchy diet.

rcd0920

Thanks so much for posting this ^_^