Many people feel very frustrated and overwhelmed because it seems like the more they try to loose weight, the more they actually gain!
Often with dieting they might loose some weight, but then just gain everything they have lost plus more! This common phenomenon is called yo-yo dieting. There are a couple of reasons why your body responds to dieting in this way, especially when the diet is very restrictive.
Firstly when we restrict food intake, our bodies perceive that we are in starvation mode, and respond by slowing down the metabolism. This means that we need less energy to maintain the same body weight. By supplying the body with a regular supply of energy we maintain a fast metabolism.
Secondly dieting has an effect the hormones that affect hunger, appetite and satiety. Two of these hormones are especially of importance. A hormone called leptin is produced in the healthy functioning body in response to the presence of fat to suppress appetite. This helps to regulate body weight. When we restrict food intake, however, the production of it is impaired and will lead to lack of appetite control. Another hormone called Ghrelin stimulates hunger and feeding. Ghrelin levels are highest in lean individuals and lowest in obese. Increased levels of this hormone are seen in people who are dieting, leading to increased hunger in dieting individuals.
It is interesting that a large proportion of women exhibit a poor relationship with food. Generally men seem to have a better relationship with food and therefore find it easier to stick to a diet and loose weight. Interestingly though, it has been found that when men start dieting, they also obscure their relationship with food and might develop binge eating disorder. This is what was found in a study conducted almost 50 years ago by the University of Minnesota (Keys et al, 1950). Young, healthy (physically and mentally) men were studied while restricting their food intake for 6 months.
One of the most striking changes observed was a dramatic increase in preoccupation with food. In the study presently discussed, the men became so preoccupied with thoughts of food and eating, that it became increasingly difficult to concentrate on usual activities. They became intensely interested in cookbooks, menus and food bulletins and started collecting recipes and even other kitchen items.
Most of the men experienced hunger during the restrictive phase of the study and for a few this led to a complete breakdown in control and subsequent bingeing episodes. Binge eating was inevitably followed by self-reproach. After bingeing one of the participants suffered a severe emotional upset, with nausea, and vomited. He felt disgusted with himself and expressed self-criticism. Sadly, during the re-feeding phase of the study, many of the subjects have lost control of their appetite and “ate more or less continuously”.
These are very common patterns seen in people following or trying to follow restrictive diets.
