Why is it so hard to lose fat?

The most basic goal of every living creature is survival and the most basic requirement for survival is energy - in the form of calories taken in from food. In order to survive in the harsh conditions that have existed for most of human history, the human body had to find a way to make the most of food when food was abundant, so that it could keep going when food was scarce. It achieved this goal in two ways: energy storage and energy conservation. When there are a lot of calories in the diet, the body uses what it needs and stores the rest in fat cells. When calories are cut back, the body conserves energy by slowing down its energy burning processes, or metabolism.

Your body will draw on the fat that is stored in your fat cells any time you reduced your caloric intake. But like an investor who doesn't want to withdraw any principal, the body "sees" its fat cells as the last resort in the fight against starvation. It is quick to make deposits into the fat bank but very slow to make withdrawals. And it is this basic biological fact that poses such a problem for modern humans, particularly modern humans who want to lose weight.

Many scientists suggest that whenever you try to lose weight by severely cutting back on calories (particularly if the cutback is drastic) your body sees the caloric reduction as a famine. It responds by going into survival mode. It slows down the basic processes of day-to- day living and the body's tissues to get some of the additional energy (calories) it believes it needs. Unfortunately, it doesn't turn to the fat cells for that extra energy. Instead, it first breaks down some of your muscle tissue, and that's bad.

Muscle cells, unlike fat cells, are active; they actually work. The mitochondria of muscle cells are like little energy plants - they are responsible for burning many of the calories we take in each day. The more muscle tissue you have, the more efficiently you burn calories. Conversely, when you lose muscle tissue, you lose some of your body's ability to burn calories. When the body uses up muscle tissue to compensate for the "starvation" of dieting, it accomplishes two tasks at once. It gets extra energy but it also slows down your metabolism.

The fact is, you can't trick your body into becoming permanently thin by temporarily depriving it of food. It's too smart to fall into that trap. It is the descendant of millions of other bodies that survived true starvation - famines far worse than anything you could impose while on a diet. As far as your body is concerned, it has one job: to keep alive and to keep those fat cells filled up and ready for the next time the food supply runs out. And there is some evidence that the more you diet, the better your body gets at its job!