Why Dieting and Strenuous Exercise Make Us Overweight and Depressed

New research shows that low-calorie dieting and strenuous exercise as part of a weight loss regimen reduces serotonin, the chemical in the brain that regulates mood and feelings of well being. This loss of serotonin leads to disruptive moods, unhappiness and, if unchecked, chronic depression.

In order to lose weight most overweight people revert to low-calorie dieting, and/or an aggressive exercise regimen. These practices have now been linked to the inability to lose or to stop gaining weight, a craving for refined carbohydrates and fats — and mood disturbances that can lead to a downward spiral of chronic depression.

 

At the beginning of a starvation diet you’ll lose a lot of weight quickly. But this weight loss is mostly water and lean muscle tissue — very little fat. You lose lean muscle tissue, the furnace where fat is burned, because your brain converts the muscle, which is a protein, into glucose (sugar) for energy. This process is called gluconeogenesis and is responsible for the look of gauntness associated with dieting.

 

Low-calorie dieting triggers your brain’s starvation defenses. The brain’s hypothalamus constantly monitors calorie or energy intake. When intake drops below, on average, 1,500 calories per day your brain interprets this deprivation as the onset of starvation.

 

To sustain your survival,  your brain holds on to fat reserves (you don’t lose weight), increases your appetite (cravings) for sugars, for quick energy, and fat for sustenance. In addition, you become tired and lethargic. You don’t want to move because doing so will help accelerate the burning of precious stored survival-sustaining fat.

 

After you give into the cravings, you eat out of control — it’s not your fault — your brain is just trying to survive — and you gain back all of the weight you lost plus an additional 20% as a cushion against a future bout of starvation (dieting). This stress on your brain and body leads to negative mood changes and ultimately to chronic depression.

 

A recent study observed that a low-calorie weight loss diet significantly lowers levels of an amino acid tryptophan and thus diminishes the positive effects of the brain’s mood regulating chemical serotonin. Tryptophan is the key catalyst in the production of serotonin.  Serotonin promotes feelings of calm, happiness, relaxation and sleepiness.  A lack of serotonin is associated with depression.

 

A reduction of tryptophan caused by dieting diminishes the production of serotonin. This sets off a negative mood and depressive downward spiral causing the overweight yo-yo  dieter to give up hope and thus lose their zest for life.

 

Most dieters think they need to engage in strenuous physical exercise to lose weight. Actually excessive physical exercise may induce the breakdown of tryptophan which can lead to neuropsychiatric symptoms such as fatigue, low mood and depression. In contrast moderate physical exercise such as walking helps increase tryptophan levels, improves mood states and helps prevent uncontrolled weight gain.

 

Thus, a balance between eating habits (avoid starvation diets, feed yourself plenteous and balanced amounts of complex carbohydrates [vegetables, grains, nuts, tubers, and fruits], protein [lean meats, eggs, beans, nuts], unsaturated fats [cold pressed olive, avocado, walnut oils, Omega 3 and Omega 6 essential fatty acid-rich foods]) and the optimal dose of

physical activity needs to be reached to effectively lose excess body fat and

enjoy a lifetime of health and happiness.