The Hormonal Effects of food
Many see food as simply energy. They remain unaware of the direct and indirect information both macronutrients (protein, carbohydrates and fat) and micronutrients have on physiology. Similar to the effect high intensity exercise has on the body, food can either elevate fat burning or induce a powerful fat storing effect. Food is able to regulate powerful hormones that predict hunger, energy, mood, and fat burning from one meal to the next.
When the proper dietary influences on your hormones are reached the process of sustained loss becomes much easier. It is known that protein and fiber together blunt the hunger response and decrease cravings. This is because they each generate a unique hormone response. Fiber drastically decreases the hunger hormone ghrelin and also lowers the fat storing hormone insulin. Protein on the other hand raises the fat burning hormone glucagon and increases the motivating and craving reducing neurotransmitter dopamine. Taken together, protein and fiber intake leads to decreased appetite, lower cravings, and improved fat usage between meals. The most interesting thing about these outcomes is that for many, they lead to effortless restriction of calories without the use of willpower. The body automatically regulates calories because it no longer has the constant urge and desire for food. Unlike the starvation effect induced by the calorie model, the hormonal approach to food sends signals that tell the body there is plenty of food and it does not have to worry about conserving fat.
Dietary studies comparing caloric vs. hormonal signals
In the 2003, May 22nd issue of the New England Journal of Medicine two different approaches to diet were analyzed. One approach was a traditional low fat and low calorie diet (LC) and the other was a diet where carbohydrate was replaced with higher amounts of protein (HP). In the high protein group dieters were allowed to eat as much food as they liked as long as they kept their carbohydrate intake low. The low calorie group limited their food intake to between 1200 and 1500 calories for women and between 1500 and 1800 calories for men. These two approaches directly compare the old method of calorie reduction versus the new method of hormonal approaches to weight loss. It turns out that the high protein group lost weight more quickly, voluntarily consumed fewer calories, and had improved blood chemistry tests over the calorie restricted group.
Another study published the same year in The Journal of Clinical Endocrinology & Metabolism (Vol. 88 # 4) found the same results. A high protein diet without calorie restriction yielded better results than the standard calorie reduction approach weight loss experts usually prescribe. This research like the study described above is noteworthy because it shows that the body has the ability to naturally regulate energy consumption. The studies above did not bother to find the underlying mechanism behind this response, but understanding hormonal influences on metabolism would enable you to predict this response.
One final study printed in the Journal Nutrition and Metabolism in 2004 looked at 28 overweight men and women. One group was given a low fat, high carbohydrate diet and the other a high protein and low carbohydrate diet. As we have pointed out these two diets will have very different hormonal effects. In this particular study the higher carbohydrate group took in 300 calories less on average than the high protein group (1855 Kcal/day for the high protein group and 1562 Kcal/day for the high carbohydrate group). Even with the consumption of more food daily, the high protein group lost more weight and fat with a greater proportion coming from the midsection.
It is important to point out here that self-reported food logs are inaccurate in terms of predicting calories. Many who read research on nutrition use this as an argument against negative results. In other words they will say, since catching calories is inaccurate, the other group must have eaten less and it just wasn’t captured. I feel this phenomenon, the fact that individuals consistently under report their food intake, is more evidence against the calorie model. We should be teaching people to make the right choices with food not expecting them to eat the right amount which they are incapable of calculating or controlling. Controlling the physiological sensations that lead to food intake in the first place (hunger, cravings, energy lows, etc), is a much smarter strategy. Eating foods that reduce these sensations will lead to less food intake automatically. It is the reason why a doughnut and a chicken breast, which have the same number of calories, will result in a very different outcome. I know plenty of people who can sit down and eat 5 doughnuts. I don’t know many who would be able to do the same with 5 chicken breasts.