Lifestyle

In fact, it is entirely possible to eat virtually no fat at all, and yet become morbidly obese at the same time, for this very important reason: it is carbohydrates, and not fat, which make us fat.

The basics of biochemistry prove this to be true. Here’s how:

Our food is comprised of a combination of only three macronutrients (foods providing energy in the form of calories): fats, proteins, and carbohydrates. During digestion, fats are burned as an immediate source of energy, and proteins are broken down to be used as building blocks for various parts of the body. Carbohydrates are converted to glucose, or blood sugar. Like fat, glucose is also used as an immediate form of energy. But unlike fat, glucose also stimulates the secretion of the powerful hormone insulin.

Insulin is an extremely important chemical whose primary duty (it actually has many functions throughout the body) is to take excess glucose from the blood, convert it to fat, and store it in the cells for later use as energy. It is important to note that calories from fats and proteins are not stored in this fashion. This is because insulin–in the role of fat-storer–is not secreted in response to fat or protein calories by themselves, as they are not converted to glucose in the same way carbohydrates are. The bottom line is this: if there is no glucose in the blood (as there would be if you consumed carbohydrates), there can be no insulin-driven storage of fat in the cells, and you will tend to not gain weight.

But we can even go a step further and say this: limiting carbohydrates is the healthiest, most effective way to not only maintain, but to lose weight.

The simple reason for this is: for any particular caloric need (and we need at least a certain number of calories to sustain our lives), decreasing one of the three macronutrients forces an increase in the others to make up the caloric deficit. If, for example, you limit your fats, the resultant loss in calories must be made up by a commensurate increase in carbohydrates and/or proteins. And since most fats are bound together with proteins, eliminating fats often means a reduction in protein as well. The body’s only adequate source of calories, then, becomes the carbohydrates.