Is your mind constantly consumed by thoughts of food? Do you tense up when you see food left on someone’s plate and wish it was socially acceptable for you to eat it? Do you spend all day fixating on your next meal and get a “high” when you go shopping for the ingredients? 

If you have never maintained a severe caloric deficit for months or dieted far below your setpoint, then it might be hard to imagine these types of thoughts ever crossing your mind. However, as many chronic dieters and disordered eaters can attest, these types of thoughts are more common than you’d imagine.

In fact, given enough time and severe enough caloric restriction, thoughts of this animalistic variety will arise in even the most mentally robust among us. That is exactly what occurred to the 36 subjects of the Minnesota Starvation Experiment…    

Minnesota Starvation Experiment

This article on Hunger and food cravings during restriction is part of a series that highlights the various symptoms that many experience from chronic dieting and overtraining. In order to examine these common symptoms, we will look at excerpts and quotes regarding the Minnesota Starvation Experiment, which is the most comprehensive study on caloric restriction and semi-starvation ever conducted. If you are not familiar with the study, or just need a refresher, you can read an overview of the study by expanding the two sections below.

Overview of Study
The Minnesota Starvation Experiment, which was conducted from 1944 to 1945 by Ancel Keys and his colleagues, included 36 healthy male participants, all of whom were men who were conscientious objectors of WW2. That is to say, they agreed to participate in the study rather than fight in the war. The purpose of the study was to examine semi-starvation with the goal of determining the most effective method of rehabilitating both starving citizens and prisoners of war come the end of the war. The observations and results of the study were meticulously recorded and later published in an over 1,300 page, two-volume book titled The Biology of Human Starvation.
Methods of Study
•Control Period (12 weeks): Approximately 3,200 calories per day, with the goal or creating a baseline for later comparison.

•Restriction Period (6 months): Approximately 1,560 calories per day and comprised of food similar to those found during times of famine: potatoes, rutabagas, turnips, bread and macaroni, etc. This period also included 22-miles of additional walking each week.

•Restricted Rehabilitation (12 weeks): The men were divided into four groups which consisted of either 400, 800, 1200 or 1600 more calories than during the restriction period. The highest calorie group was basically back to baseline calories, while the lowest calorie group was just under 2,000 calories.

•Unrestricted Rehabilitation (8 weeks): In the period, the men ate ad libitum, meaning that they ate as much as they wanted. For most men this ended up being around 5,000 calories per day, however, a few of the men ate as much as 11,500 calories on some days.

(Keys, 1950, pg. 70)

Health Context

To fully appreciate the impact that this experiment had on the psyche of these men, I want to give some context to where these participants were healthwise before the study. In order to ensure that the changes observed in the experiment could be attributed to caloric restriction rather than external factors, the researchers selected only volunteers who were in peak physical and mental health. After a series of health assessments and phycological evaluations, only 36 out of several hundred volunteers were ultimately selected. 

Cultural Context

It is also important to consider the cultural contexts of the 1940’s from which this experiment took place: dieting was rare, processed food was nascent, and the ideal body image, at least for men, was of little concern. 

Consider this quote by one of the participants regarding his weight gain post recovery, “Now, eight months after the end of starvation, I am fat and healthy.” – Could you imagine this coming out of the mouth of someone today? Me neither.

Food Fixations & Hunger From Restriction

  • I’m hungry. I’m always hungry —not like the hunger that comes when you miss lunch but a continual cry from the body for food. At times I can almost forget about it but there is nothing that can hold my interest for long. I wait for mealtime. When it comes, I eat slowly and make the food last as long as possible.  (Keys, 1950, p. 852).
  • All food tastes good. Even dirty crusts of bread in the street look appetizing and I envy the fat pigeons picking at them. No food is wasted and the sight of people wasting it in restaurants is intolerable(Keys, 1950, p. 852).

I Can Relate With These Obsessive Food Thoughts

During the summer of 2018, when I was deepest in my restriction and bulimia, my food obsession was at an all-time high. I vividly remember walking past a bakery and seeing a large clear garbage bag filled with bagels in the trash on the street. They must have thrown them away because they were stale, but the thought of these going to waste, stale or not, was devastating to my starving self. 

My heart raced as I imagined how great it would be to have some and devised a plan in my head to make that a possibility. I walked around the block, passing this stale bag of bagels several times; with each pass the tension grew more intense until my rational brain was finally able to convince my reptilian brain that it was a bad idea. I quickly left while I still had control because I knew from experience that the voice in my head would be back and given a second chance he might win.

Food Takes Center Stage

  • Things that would arouse their interest: loss of body weight, hunger, and food. In discussing these, the men would often become animated (Keys, 1950, p. 836).
  • Food in all its ramifications became the principal topic of conversation, reading, and daydreams for almost all Minnesota subjects. When they read books or attended movies, they were much impressed by the frequency with which food and eating were mentioned (Keys, 1950, p. 853).
  • If we see a show, the most interesting part of it is contained in scenes where people are eating (Keys, 1950, p. 852).

Binging On All Things Food

Not long after I started extreme dieting, I became fixated on show about food. It was not uncommon for me to watch shows like Man Vs. Food or other Cooking Channel shows 24 hours into a fast. The hungrier I was, the more these shows appealed to me.

This habit continued throughout my time with my eating disorder. I can remember an entire semester when I would accompany my food binges by binge watching this British show called Supersize vs Superskinny. Looking back, it’s a rather silly show, but the way it showed the participant eating each other’s diets was really captivating in that restricted state.

Social Isolation

  • Social graces, interests, spontaneous activity and responsibility take second place to concerns of food. I lick my plate unashamedly at each meal even when guests are present. I don’t like to sit near guests, for then it is necessary to entertain and talk with them. That takes too much energy and destroys some of the enjoyment that comes from my food (Keys, 1950, p. 852-853).

This desire to be isolated socially is very common in disordered eaters

It’s sad to admit but I would get annoyed and stressed out if someone or something would interfere with my plans to binge. I remember thinking many times, I wish everyone would just go to sleep so I could finally raid the pantry. I always felt really guilty about these thoughts.

This tendency was also true when it came to dieting. For instance, If I had plans to get back on a strict diet, but then someone invited me to go out on the weekend, I would get really frustrated. I would think, damn, my plans are all messed up. Now I have to wait until after the weekend before I go back to my diet.

Unusual Eating Habits From Restriction

  • The men often reported that they got a vivid vicarious pleasure from watching other persons eat or from just smelling food. Large quantities of water were consumed with and between meals, and the subjects increased the bulk of their food by “souping.” (Keys, 1950, p. 829). 
  • The men attempted to keep the stomach full by consuming large amounts of liquids and felt they were less hungry as a result. It is known that under conditions of natural starvation people fill their stomach with all kinds of materials, even clay(Keys, 1950, p. 829).
  • Excess Coffee & Tea Consumption: Some of the men increased their consumption to 15 or more cups daily, it became necessary to limit all subjects to a maximum of 9 cups per day(Keys, 1950, p. 835).
  • Gum Chewing: chewing rapidly became excessive. Heavy gum chewers would take 2 or 3 sticks at a time, chew them until the sweet taste was gone, discard them, and then replace them with fresh sticks in chain fashion. One of the men chewed up to 40 packages of gum per dayand developed a sore mouth from such continuous exercise. Thereafter, the use of gum was restricted to 2 packages a day (Keys, 1950, p. 835).
  • Odd Food Combinations: In many cases the men were not content to eat “normal” menus but persevered in their habits of making fantastic concoctions and combinations. The free choice of ingredients, moreover, stimulated “creative” and “experimental” playing with food (Keys, 1950, p. 843).

Food Concoctions

The act of making strange food combinations is quite common for those with disordered eating. In fact,“a study of 407 college students plus 45 patients being treated for compulsive overeating or binge-eating disorders, 24.6% reported that they sometimes concocted food mixtures for themselves that they were too ashamed or embarrassed about to make in front of others.” (Q&A, 2017).

I certainly made strange food combinations

In my experience, these behaviors would increase in proportion to the severity of my caloric restriction and body fat levels, which is not surprising. While I can’t speak for everyone, for me, this was a way too increase the high of binging: effectively getting hits of dopamine through both heightened anticipation and the novelty of new combinations.

As I wrote about recently, another instance in which these food combinations are common, though possibly for different reasons, during the initial stages of satiety recovery

Trading Sex for Hunger

The chart portrays the approximate severity and length that hunger and cravings were affected. The letters at the bottom C, S, and R represent the control, starvation, and rehabilitation periods respectively, while the numbers represent the number of weeks into the period. As you can see by the food drive curve at the top, hunger rose throughout the restriction period reaching its peak during the final week before rehabilitation.

Following the initiation of the refeeding period, these hunger ratings began to return to normal, though still only slightly more than 50% recovered 12 weeks into rehabilitation. Also noteworthy is the inverse correlation of hunger with both libido and activity drives. For more on the effect of this experiment on the sex drive of the participants check out my article here. (Keys, 1950, p. 823).

Symptoms at Week 24 of Restriction

During the final week of restriction, participants were asked to assign a rating to their various symptoms. The items in which there was the greatest amount of deterioration during starvation were: “tiredness” (+3.5), “appetite” (+3.1), “muscle soreness” (+2.1), “irritability,” “apathy,” and “hunger pain” (+1.8), and “ambition,” “self-discipline,” and “concentration” (—1.8) (Keys, 1950, p. 821).

*An increase in the particular symptom was rated on a scale from More = 1 to Extremely More = 5; a decrease was rated on a scale from Less = —1 to Extremely Less = —5 

Takeaway

An important insight that I think we can get out of this experiment is that food fixations and disordered eating doesn’t always arise from some deep emotional problem or even the cultural pressure to have an ideal body–all it takes is enough restriction and enough time

If you think someone could benefit from hearing this message, please share with your friends and family. ✌️

References:

Keys, A. B. (1950). The Biology of Human Starvation (Vol. I & II). Minneapolis: University of Minnesota Press.

Q & A: Weird Food Combinations. (2017, January 30). Retrieved from https://eatingdisordersreview.com/q-a-weird-food-combinations/