Consuming such few calories had rather dramatic side effects: after a few months, there was a large increase in depression, hysteria, hypochondriasis, self-mutilation, and declines in sexual drive. The subjects were constantly thinking and dreaming of food. There were large declines in their basal metabolic rate to try to adapt to this dramatic new level of calorie intake. When the subjects were finally given the opportunity to eat as much as they pleased, many ate until their stomachs were packed to capacity, yet still felt hungry.
What is even more interesting than these responses is that they were almost entirely forgotten in the treatment of obesity.
By today's standards, the subjects in the Minnesota study were not eating a starvation or semi-starvation diet. They were eating 1547 calories a day, almost precisely the same amount of food prescribed today to men their size who want to lose weight. For the men enrolled in the starvation study, their calculated calorie intake that would supposedly elicit weight loss of 1 pound per week was 1570 calories, according to the widely-used Mifflin St Jeor equation. How can anyone be expected to lose weight this way and keep it off?
According to the Centers for Disease Control and Prevention, weight loss is the result of following a simple formula. To get rid of excess body fat, all you have to do is “use up more calories than you take in. Since one pound equals 3,500 calories, you need to reduce your caloric intake by 500—1000 calories per day to lose about 1 to 2 pounds per week.” We should therefore limit the amount of fat we eat, since it has 9 calories per gram.
This simplified logic suggests that the underlying regulation of our energy intake takes place at our mouths. Once it enters the body, it does not matter whether you ate 100 grams of sugar or steak, the calories will be utilized, stored, and distributed equally. This also places the entire blame for becoming overweight or obese on the person's conscious behaviors, and creates an incredible lack of empathy in the medical community. People get fat because they eat too much. It is just that simple.
But what if instead we asked the question of why?
Why are they eating too much? Maybe, just like every other self-sustaining behavior in every creature on the planet, our decisions and desires to eat more or less are regulated at the cellular level. What if they eat too much because they are fat? What if eating too much is correlated with - and not causing - obesity?
Why is there no mention of the hormonal and biochemical regulation of our fat when we talk about gaining or losing fat? It makes no sense and it is why I have created this website. It seems to me that if we want to learn what makes people fat, we should study the fat.
By definition obesity results from too many calories being stored in one's adipose tissue. Why are more calories being stored in adipose tissue as opposed to being used for fuel? What hormones are involved in either directing calories to be stored in our fat cells or inhibiting those stored calories from being mobilized into the bloodstream?
There are multiple hormones that regulate your fat cells, but by far the most potent one is insulin. When insulin is high, calories are taken up into the fat cells by an enzyme called lipoprotein lipase. Insulin also simultaneously inhibits the release of calories into the bloodstream from the fat cells via its effects on another enzyme (Hormone sensitive lipase). This is true and uncontroversial.
The next absolute truth is that the most potent stimulator of insulin is carbohydrates. This is somewhat controversial because protein spikes insulin as well, but fat does not. So a diet composed of 60-65% carbohydrates, 10% fat, and 30% protein, the generally accepted healthy diet, is quite good at stimulating insulin when compared to a low carb diet composed mostly of fat and protein. The more insulin there is, the more calories are stored as fat. At least according to every biochemistry textbook.
What makes this idea even more palatable is the amount of clinical evidence there is to support it. If a low-calorie, low fat diet is the best way to lose weight, than one would imagine that some shred of clinical evidence exists to prove this. In fact, quite the contrary is true. A low-fat, low calorie diet has never outperformed an ad-libitum (eat to your heart's desire), high protein, high fat, low carbohydrate diet. Never. Read more about this in the related science section.
The randomized clinical trials testing the safety and efficacy of low carb diets compared to low fat diets come to a few consistent conclusions:
- The low carb group usually - but not always - loses more weight. However, the low fat group never loses the most weight.
- The low carb group sees larger increases in HDL (good cholesterol, and much larger decreases in triglycerides, with small or non-existent increases in LDL (bad) cholesterol
- The low carb group sees more weight loss despite always reporting feeling full
- The low carb groups always see their LDL particles in their blood switch from small, dense, atherogenic particles, to large and fluffy. Small, dense LDL particles are associated with heart disease.
There are two possible explanations for the observed weightloss. Either something about a low carb diet causes you to spontaneously eat less, thus losing weight via the conventional explanation. Or, the alternate hypothesis would predict, that the extra weight was lost because of the net decrease in insulin levels.
In my next post, I will address this issue.