Episode 042: On this week’s episode of Real Health Radio I’ll be discussing The Minnesota Starvation Experiment.
This fascinating experiment has had a huge impact on me as practitioner so I want to share some insights about it with you. I explain the background of the experiment and why it happened, what took place as part of it, and what the results were. As I go through I also explain why I think this information is so useful, both for those who diet but also for those that suffer with eating disorders.
00:00:00
00:01:00
00:03:00
00:04:30
00:06:00
00:07:05
00:07:35
00:08:40
00:09:15
00:20:20
00:21:25
00:24:00
00:28:35
00:31:20
00:32:50
00:00:00
Chris Sandel: Welcome to Episode 42 of Real Health Radio. You can find the links I talk about as part of this episode in the show notes. That’s at www.seven-health.com/042.
Welcome to Real Health Radio: Health advice that’s more than just about how you look. Here’s your host, Chris Sandel.
Hey, everyone. It’s Chris Sandel here, and welcome to another installment of Real Health Radio. This week is another show where it’s me on my own. I’m sitting in front of my laptop and talking about a particular topic. Today’s chosen topic is the Minnesota Starvation Experiment. Two weeks ago I released a podcast about an overeating experiment I did at the start of the year.
00:01:00
I then used that overeating experiment to launch into a talk about weight and weight loss and calories in and calories out and a whole load of stuff along those lines. This episode did extremely well. Within 4 days, it was my second most downloaded show of all time. I’m recording this episode a week in advance, as I’m going to be on holiday from tomorrow, and when this actually comes out, I’ll be in the South of France. But I would wager quite a bit of money that by the time that this goes live, that overeating experiment podcast will be the most downloaded show I’ve done of all time.
So I’m going to link to that show again in the show notes, so for anyone who missed it the first time around, I would highly recommend checking it out.
I’ve always found the Minnesota Starvation Experiment really fascinating. I wanted to go into a bit of detail on it because it seems that these kinds of experiments, if I’m looking at how well my last podcast did, are something that also fascinates other people. It’s an experiment that would never be able to be done today for ethical reasons, and it’s why I think if we can then look at this in such great detail, it can provide us with a real wealth of knowledge.
I know for me personally, this study and the reading that I’ve done around it has had a huge impact on the way that I think about metabolism and body weight and cravings and food behaviors and just so much more. It really has had a big impact on me as a practitioner.
What I want to do is explain about the experiment, what took place, what the results were, and as I’ll go through, I’ll explain why I think this information is really useful – and this is both from a dieting perspective, but also for those who suffer with eating disorders. This is going to be a much shorter episode than the last solo one. The last solo one was like 2 hours 15 minutes. But hopefully you’ll still find it just as insightful.
00:03:00
The Minnesota Starvation Experiment was conducted between 1944 and 1945. The Second World War had created conditions that meant that it was likely that millions of people in Europe and also in Asia were going to face severe famine. Through the experiment, what they hoped to glean from it was to look at how the body reacts to starvation and to look at, because of that and the information they got from it, solutions that could be useful with the impending food shortage and also how people move out of being in a starvation state.
Rather than simply just focusing on the nutritional requirements for say refeeding a starving person, the study wanted to look at other insights about how starvation – or as part of this study, it was really semistarvation – how that, to quote the researchers, “alters the changes in motivation, then behavioral consequences or physical changes, and finally, the emotional, intellectual, and social changes which so profoundly influence the personality.” So they really wanted to look at starvation from every different angle to see how it would affect individuals so they could then have a better understanding of how that was going to affect population level if the impending famine was to take place.
00:04:30
The person who was head of running this study and then wrote a massive two-volume, 1300-page opus on the experiment is a guy called Ancel Keys. Most people know the name Ancel Keys because of his connection with the low fat movement and making the connection between cholesterol and heart disease. This is stuff that he’s done subsequent to his study. That was stuff that he did in the ’50s and ’60s, whereas this study was back in the mid-’40s.
In a lot of circles, Ancel Keys is portrayed as this bumbling scientist who was very selective in his figures that were used and that this is the reason we got into this whole low fat diet trend in the 1980s. This idea or myth around Ancel Keys really isn’t correct, and I highly recommend people checking out Denise Minger’s book Death by Food Pyramid. She’s also written other articles on it that really looks at Ancel Keys, the whole low fat movement, and sets the story straight on this stuff.
I know this is slightly digressing from the starvation experiment, but for all the hate that is thrown at Ancel Keys, the majority of it is totally unwarranted. If you look at his earlier work and what he’s done in terms of the starvation study, he’s provided so much good information for the scientific community.
00:06:00
Back to the study. There were 36 men who were used for or were part of the study, but in the end only 32 of them were used in the final evaluation. I’ll explain later on why that was the case. The subjects were all white males ranging from 22 to 33 years of age. The final 36 were picked from an original group of 400 men, with candidates chosen because of their mental and physical health and their commitment to the study. They were strong, healthy men who were conscientious objectors, so they didn’t want to fight in the war, but they were happy to support the country by participating in this study.
The men as part of the study had some pretty basic daily work assignments. They were required to walk 22 miles a week, and they also had to keep a diary, but aside from the mealtime, there really weren’t any restrictions placed on these guys’ social lives.
00:07:05
The study started with 12 weeks of a control period where the men would eat approximately 3,200 calories a day. This was to get them to their ideal weight, and it was really to create a calorie balance. This was roughly what they were normally eating in everyday life – and a lot of these guys were doing physical labor. I know the calories look quite high as part of that, but that was what was needed for them to be maintaining their weight and maintaining calorie balance.
00:07:35
One thing I would say with the figures of the 3,200 calories and then the figures I’m going to talk about later in terms of the restriction part of the experiment is it’s likely these figures were possibly a little lower than they actually appear.
I don’t want to go into a whole history lesson around calories, but what I would mention is that the amount of calories that are in a food isn’t necessarily what someone gets out and is able to digest. Lots of the figures that we use today to work out calories are modified numbers that are based on some figures that were then released in 1955 that took into consideration this ability to digest different foods in different ways. So as this experiment was down prior to that – nearly 10 years prior to that – some of the calorie figures may be a little bit out, and they may appear slightly higher because people couldn’t digest all the food that was in them.
But in the whole scheme of things, I’m really just nitpicking with this, and I just wanted to mention it.
00:08:40
After that initial 12 week period of the control period, the next 24 weeks were the starvation or the semistarvation part of the experiment. During this part, the men had their calorie intake cut to approximately 1,560 calories a day. During this 24 week period, the men lost approximately 25% of their body weight, which was on average 16.5 kilos or 37 pounds.
00:09:15
As part of that, they experienced lots of different common symptoms that I want to go through as part of this. During this period, their basal metabolic rate plummeted, and it fell by as much as 50%. Your basal metabolic rate is the rate of the calories that your body uses to do its most basic functions. I often describe this for people as what you would use within a coma to do the basic functions of rebuilding, to do very basic digestion. What happens is if there’s not enough coming in, that basal metabolic rate just drops right down. So even if you’re not covering the basics, it’s like “we don’t have enough.”
They also had a decreased pulse. Pulse would drop, and for some individuals it was around 30 or 40 beats per minute at rest. This is another common sign for people who have really low metabolic rate that their pulse starts to come down.
There was a real increased sensitivity to cold. All the men wore heavier clothes, much more layers. They wanted to have hot baths and boiling hot drinks and hot food. They had freezing cold hands and feet, and their skin in general.
They had a real increased tolerance for heat. For example, the subjects could hold really hot plates without any discomfort, and they asked for their food, for their coffee, for their tea to be served unusually hot. The men unsurprisingly felt like little physical activity and doing physical exercise, and they spent a lot of their time just lying in the sun trying to keep warm. Tea and coffee intake increased, and the satisfaction that the participants got from having these drinks markedly increased. When some of the men were hitting 15 cups a day, it started to cause problems, so they set a 9 cup a day limit on coffee and tea.
They started to have a real thirst for water, and I think a lot of this was to drink more water to get that sense of fullness. Some of them would start to take up smoking to stave off hunger. Others chewed lots of gum. When some of them started chewing up to 40 packs of gum a day, the laboratory then started to set a maximum on this so that they could only have two packs a day, because they were doing lots of damage to their mouth, getting ulcers, etc., from chewing so much gum.
There was real increased amounts of irritability. There was a decreased interest in sex, with much less frequent erections. As time went on as part of the starvation, the men’s desire became almost nonexistent. There were some subjects that this didn’t impact as much, but for the vast majority of it, their interest in sex basically disappeared.
This wasn’t just about the desire, but it actually affected their reproductive abilities. For example, they took sperm samples during the final week of the starvation experiment, and then they also took sperm samples after 20 weeks of refeeding (and I’ll talk about the refeeding in a sec). When they looked at the sperm motility when they were in that last week of the starvation period, on average the sperm would swim for 4.8 hours. After the 20 weeks of refeeding, the sperm motility and how long they would swim for was 25.5 hours. So a huge difference. If we’re looking at reproductive ability, sperm that’s only going to swim for 4.8 hours isn’t going to do very well in terms of getting someone pregnant.
There was much lower amounts of red blood cells. Red blood cells are the ones that carry oxygen around the body, so they developed an anemia of sorts. Certain white blood cells were also decreased, and this was as high as a 30% decrease. White blood cells are part of your immune system. There were actually other white blood cells that increased, and sometimes this increase can be associated with autoimmune type issues or the immune system not working so well. There’s often increased numbers, but the ability of those cells to function properly is greatly reduced.
Their hair would grow much more slowly and it would fall out prematurely. Their nails would grow much more slowly or they actually stopped growing.
The men developed really strong cravings for salt.
They developed different signs of mental illness, and this got worse, again, as the starvation period went on longer. For example, one of the men “accidentally” cut off three of his fingers while chopping wood. To give you a perspective of his mental state, he was later quoted as saying, “I admit to being crazy mixed-up at the time. I’m not ready to say I did it on purpose. I’m not ready to say that I didn’t.”
Food obsession became a really big part of this. Food became the principal topic of conversation and their thoughts. They read books about it. They’d be reading cookbooks and menus, and information on food production became intensely interesting to many of the men who’d previously had no interest in diet or agriculture. There were reports of men staying up till 5:00 in the morning reading through cookbooks. A few, as part of their diaries, even planned on becoming cooks and opening restaurants once the experiment was over.
To quote one of the researchers, they said, “They would coddle their food like a baby and handle it and look after it like it was some kind of gold. They played with it like kids making mud pies.” There was this real interest when the food was given to them, and how this then changed their behavior.
There was also a lot of plate licking that became very commonplace, and ways that the men would look for of extending mealtime or extending their sense of fullness as part of this. They would dilute their potatoes with water. They would hold the food in their mouth for a much longer time before swallowing it. There’d be these bizarre rituals in terms of how they would eat their food and the order of eating it and how they would divide it up on their plate. They’d be doing this labored combining of different foods on their plate – really overly bizarre behaviors that started to develop around eating and eating rituals.
Sticking to the restricted eating became more and more difficult as the experiment went on, especially then when they went into town or places where food was available. One of the subjects was eventually eliminated from the project for sneaking unauthorized food while they were in town. This sneaking of food in this individual initially led to a really big high, and then it was followed by a real depressive low.
To quote one of the researchers when talking about this experiment where he’d sneaked food while he was in town and then he’d stopped off at all of these other different shops, he said, “He kidded with the fountain girls, thought the lights were more beautiful than ever, felt that the world was a happy place. Then this denigrated into a period of extreme pessimism and remorse. He felt he had nothing to live for, that he had failed miserably to keep his commitment of staying on his rations.”
In total, four of the subjects as part of the experiment were excluded, and they had reactions that would be defined or described as character neurosis. The men were then unable to stay on this semistarvation diet. Two of the subjects, their response to the stress was particularly violent and bordered on psychosis. Obviously one of the men I talked about earlier, who chopped off his fingers as part of the experiment was one of the men who was exclude.
The men aged prematurely, and this is in terms of both their appearance and how they looked, but also their functioning. There was low blood pressure and regular dizziness on standing – getting out of bed, getting out of a chair. This dizziness could be just normal dizziness, it could be something like vertigo. Some men would even experience momentary blackouts because of the low blood pressure or other things going on within their body.
They would have frequent urination, like day and night, constantly urinating. Constipation became a real problem. To start with, the men were going once a day. Towards the end and as the experiment went on, they were maybe going twice a week, once a week.
Cuts and bruises would heal very slowly. They’d start to get muscle cramps. Muscle pain was really common. Their skin became very rough, and it became very thin. There was a loss of ambition. They had real difficulty concentrating and increased amounts of depression. They spent more and more time on their own and wanted to be more alone. The men became very reluctant to plan activities, to make decisions, to participate in any kind of group activities.
There’s a really great quote that I want to share with you from one of the participants that really sums everything up. He said, “I’m cold, I’m weak, and now I have edema [which is water retention]. Social graces, interests, spontaneous activity, and responsibility take second place to concerns of food. I don’t like to sit near guests, for then it’s necessary to entertain and talk with them. I am one of about three or four who still goes out with girls. I fell in love with a girl during the control period, but I see her only occasionally now. It’s almost too much trouble to see her, even if she just visits me in the lab. It requires effort to hold her hand. Entertainment must be tame. If we see a show, the most interesting part of it is contained in scenes where people are eating. I couldn’t laugh at the funniest picture in the world, and love scenes are completely dull.”
I think that gives a really good snapshot into how the starvation part of the experiment started to affect someone not just from a physical perspective, but from a mental and emotional perspective and their outlook on the world.
00:20:20
Following on from the 24 week starvation period, there was then a period called restricted rehabilitation. This restricted rehabilitation lasted for 12 weeks, and the men were split up into different groups and were given varied diets as part of this restricted rehabilitation to analyze the benefits of say different proteins or different supplement regimes. This part of the experiment was to help understand what would be the best rations as part of the refeeding if the world was to fall into the mass food shortages that could possibly happen.
What came out of this 12 week restricted rehabilitation wasn’t all that fruitful because the calories were still really low in comparison to what these men needed, and there wasn’t much improvement. There wasn’t much difference between the different diets that these men were put on as part of that restricted rehabilitation.
00:21:25
The final period was then 8 weeks of unrestricted rehabilitation. As part of this, the men could eat whatever calorie intake and whatever food content that they wanted. During the first week of unrestricted rehabilitation, the individual intakes of calories varied from 4,400 calories to as much as 10,000 calories per day. Some of the men commented that they were still hungry at the end of eating very large meals, even though they were unable to ingest any more food.
I talked about, as part of my overeating experiment, having a similar sensation where I would be really full and then really hungry at the same time, in this limbo land where I wasn’t really knowing what the body really wanted.
During the unrestricted rehabilitation period, the men rapidly put on both weight and body fat, and they saw health improvements as part of this rehabilitation, with some of them being pretty instantaneous. In a 3 day period, one subject gained 6 pounds and has resting pulse go from 36 beats per minute to 60 beats per minute. Another participant had his BMR (basal metabolic rate) nearly double in a 3 day period. Not everything improved this quickly, and there were lots of things that took a long time to improve, but some of it did.
But at the end of 3 months of rehabilitation – that’s 3 months of eating an unrestricted amount, eating whatever they wanted – even for those subjects who were maintaining the highest calorie intake, their overall physical condition was considerably inferior to their pre-starvation status. Later reports from the subjects really indicated that it was not until an additional 3 months on top of that, so we’re talking about 6 months of normal living and super normal eating, that their physical capacity started to get back to something approaching their pre-experiment levels.
Some of the subjects continued to binge to the point of sickness, and this is even 8 months after the study was over. There was at least one of the participants who was hospitalized for several days after having to have his stomach pumped because of eating so much food.
00:24:00
It’s interesting to look at what happened to these subjects from a weight perspective. After eating 12 weeks of as much as they wanted, their body fat percentages matched up where they were at pre-experiment levels despite the fact that they weighed a lot less. This is very common in refeeding, especially when calorie intake is high. Fat deposits tend to increase at a much faster rate than the active tissue – things like muscles and organs, which have previously been broken down to be used as an energy source. Fat is given preferential treatment in the order of healing, and fat goes on first before any of this other stuff.
This is why in recovery from restrictive eating disorders – things like anorexia – getting someone back to where they were at pre-disorder weight isn’t where the recovery should stop, because at this stage the body has only been prioritizing the fat gain as opposed to rebuilding the muscle and rebuilding the organs. Really, weight needs to go much higher than this.
If we go back to the experiment, 8 months of unrestricted eating after the starvation period, the men had their lean body mass restored to their pre-experiment levels, but their abdominal body fat was 40% higher than when they started. They’d got back to where their lean mass was after 8 months, but their body fat was now much higher than when they started.
But it was around this 8 month period that the fat levels really started to hit that ceiling and started to drop down despite the fact that the men weren’t now dieting, the fact that the men were just eating to satiety. This then continued on. It was by about 46 weeks of this unrestricted eating that the weight and the body fat percentages had returned to basically pre-experiment levels. This is the men using hunger cues and eating what they needed for their body, and it then naturally started to return to the weight it had been before they started.
If we look at body weight and body fat throughout the experiment, at the start, body weight started to drop down as part of the starvation, which is as you would expect. Then when they started to eat an unrestricted amount, it then naturally came back up and went way higher than it was to start with, and then it started to come back down basically to baseline levels.
The same thing happened with their body fat, but to a much higher degree. During the starvation point, their body fat dropped down much more significantly than their total body weight, but also, when they did the rehabilitation, they ate more, their body fat then came up way higher as a percentage than their weight did. But as time went on and the longer they kept this up, the more it started to come back to close to where it started.
I will just say that the weight didn’t come all the way down to where it had started again. The differences range from 0.7 of a kilo above where someone started all the way up to 7.2 kilos above where they started. If I’m doing that in pounds, you’re looking at roughly 1.5 pounds heavier than where they started, or being somewhere around 13 or 14 pounds heavier than where they started.
I don’t have information, and I don’t think it was tracked, on what happened to these men a year after this or 5 years after this. I don’t know how many of these men lost further weight to get closer to their original starting weight, or how many of them then gained weight. But what I would say is based on the available information, this seems to indicate that by eating to satiety, weight can come back to where it started or close to where it started for some individuals, whereas in other cases the weight set point that someone sits at is then affected due to starvation or due to dieting, and this can then lead to them sitting at a higher level than where they previously started.
While I think the health side of things is really important, let’s just put that to the side for a moment and focus on weight.
00:28:35
When someone restricts their calories – and if we’re talking about outside of this experiment, in a real world situation – when someone restricts their calories – and this can be either through conscious restriction, through conscious dieting, or it can be someone who isn’t realizing they’re eating in a restricted way, but because they’re eating healthy or because they’re really busy and they’re not prioritizing food, their calories become low. This in a sense is doing the same thing as was happening in the experiment. When this low calorie intake ceases, what happens?
What happens is weight goes on with a disproportionate amount in the beginning being put on as fat rather than as lean muscle. What happens normally in a real world situation when this happens is there is an unfortunate knee-jerk reaction of someone thinking “oh damn, I need to change this,” so they start restricting again. They try and lose weight again. Some weight is lost; they then stop dieting, and then fat is added again.
They get into this vicious cycle where someone feels trapped, and with each extra diet, their weight goes up maybe a little bit more. Or even if the weight comes back to where it was before they start dieting again, the percentage of body fat starts to increase higher and higher and the percentage of lean tissue comes lower and lower because of how the body then prioritizes that as part of those rebuilding.
I think one of the biggest lessons for the experiment is what happens with the body when it’s given what it needs to heal. At first the weight is stored as fat, but with time, things start to change, and the body then in a sense realizes that it doesn’t need to be storing so much for a rainy day and that there can be decent amounts of food that’s going to be coming in next week, next month, so the body can start to shift to let more of that weight drop off, to start to put more of its resources into rebuilding the lean tissue as opposed to just storing fat, and the body can then start to return to a lower weight through normal eating and normal living.
I’m by no means saying that this will happen to every person in every situation, but it does go to show that weight is so largely dictated by unconscious processes that are dictated by the body and that when you give the body what it needs and in a lot of ways get out of the way, it can start to do a lot of those functions on its own.
00:31:20
It’s interesting for me when I look at the list of symptoms that the men experienced during the starvation phase because this covers nearly everything that people come and see me for – constipation, reproductive or libido issues, always being cold, irritability, moodiness, frequent urination, muscle pain, water retention. Undereating is a huge cause or a very likely cause of all of these things. I’m not saying that it is the only cause, and I’m not saying that it is the only component, but it is often a big piece of the puzzle.
Maybe I only see a certain percentage of the population, so making generalized comments about what happens at a population level maybe isn’t the best idea. But from what I do see, I would say that large sections of the population are undereating from what their body needs, and this is leading to a lot of the symptoms that they are then getting.
And this can be people who have very different body shapes and sizes. I think in a lot of people’s minds when they think of someone who’s undereating, it’s someone who’s skin and bones. They have this picture in their mind of someone who’s very petite or someone who looks underweight or looks malnourished, but that isn’t always the case. You can have someone who’s heavier who is still in a very malnourished state.
00:32:50
The final thing I want to mention before I wrap this up is in relation to eating disorders. For lots of people who end up with an eating disorder, especially something like anorexia, it often first started out as them going on some diet. Maybe they had a friend’s wedding coming up or they were going on holiday, so they went on some restrictive diet, and now it has unfortunately just spiraled.
If you then fast forward, they find themselves restricting their food, but having lots of obsessive thoughts around food, having ritualistic or seemingly weird eating behaviors. It starts to affect them socially. There’s lots of anxiety. They don’t want to participate as members of society. There’s a lot of isolating.
For a lot of people that I talk with in this situation, often there’s a feeling that they want to get on top of this mental/emotional stuff and their relationship with their food and their neuroses around food and society, and then they can start to eat more, like they need to deal with that other stuff first, and then they’ll get on to the eating.
But as this study clearly showed, a lot of those problems are created simply by being in a starvation state. Someone’s not going to get over these thoughts around their eating and around anxiety, etc., until they have started to eat and until they have started to eat a significant amount of calories and done this for an extended period of time.
I know that eating disorders like anorexia aren’t purely because of lack of calories and that just getting someone to eat more food won’t erase everything that is going on. But it is a big component of it, and if someone is not eating the food, then the likelihood of someone improving their thoughts around their body and their worldly outlook isn’t really going to change. This stuff really can’t be the first thing that changes and then someone deals with the food. It has to be the other way around.
From a body weight perspective, the pattern that is seen as part of this starvation experiment is the pattern that is part of recovery. Getting someone back to their original weight and then maintaining that really isn’t enough. There needs to be an increase above their original weight for proper repair to take place. There can be lots of not-very-nice symptoms that go alongside this apart from just the weight gain. There can be lots of water retention, there can be lots of puffiness, there can be lots of skin outbreaks. For someone who is overly worried and anxious about their appearance and this has been part of the drive into why someone has an eating disorder, this can be really difficult to deal with.
But the sad reality is there’s no way around this stuff. Believing that this can be avoided or seeing it as not fair or believing that something else should happen doesn’t change that fact. If people aren’t willing to go through this, then there isn’t really a way to get over it. I know this isn’t often what people want to hear, but it is the sad reality. At some point, the pain of staying where they are will start to outweigh the pain of change. This is when the change then becomes doable.
This is the end of today’s show. I hope that you have found the Minnesota Starvation Experiment as fascinating as I have and that it’s helped to explain certain things that occur when people under-eat. It’s not just because your body is broken or that you’re going through something that no one else does. It’s because of basic physiology and how the body reacts to starvation. I think it’s an important thing to remember, because so often people can think “it’s just me, this doesn’t happen to everyone else,” and in reality, this happens to anyone who starts to drop their calories or restrict their food in a way that leads to starvation or semistarvation for the body.
I will be back next week with another show. That show will be with a guest, but until then, have a great week and I’ll speak to you then.
Thanks for listening to Real Health Radio. If you are interested in more details, you can find them at the Seven Health website. That’s www.seven-health.com.
Thanks so much for joining this week. Have some feedback you’d like to share? Leave a note in the comment section below!
If you enjoyed this episode, please share it using the social media buttons you see on this page.
Also, please leave an honest review for The Real Health Radio Podcast on iTunes! Ratings and reviews are extremely helpful and greatly appreciated! They do matter in the rankings of the show, and I read each and every one of them.
And finally, don’t forget to subscribe to the show on iTunes to get automatic updates.
Thanks for joining me on this episode. Here is a link to see the other shows. Until next time!
Policies
Social
Copyright © 2012 – 2023
seven-health.com · All Rights Reserved.
hello, been listening to your podcast which has been helping me alot in my remission from disordered eating. I find that the podcast of about 30mins are best for the listeners as longer ones require a lot more time and energy to listen to completion. just a tiny feedback. thanks once again!
[…] Real Health Radio Podcast – The Minnesota Starvation Experiment […]