Food Energy & Weight Loss

Below is an excerpt from Part Two of

The 2004 Multi-Diet

by Anderson A. Anonymous, M.D., Ph.D.

Fat is for Storing

A large number of experiments over the past 15 years have consistently demonstrated that the body’s initial “preference” for handling dietary fat is to store it as body fat. A normal meal usually provides fat, carbohydrate, and protein. During the digestive process, the fat is “packaged” in the form of chylomicrons. In this form, it cannot be used as energy by the cells. The chylomicrons are absorbed into the bloodstream where they circulate until “cleared” from circulation by being picked up by fat cells all over the body. The fat cells “unpackage” the fat and either store it or release it into the bloodstream as “free fatty acids” (depending on the body’s energy need at the time). Free fatty acids are the form in which fat can be used for energy by other cells.

The important point is that all dietary fat first gets stored in fat cells before it gets released for energy (except for very small amounts under very unusual circumstances). Hence, “fat is for storing”. This is one reason to try to eat as little fat as possible in meals.

However, when they read this, some people (not you, of course ) always think: “OK, I just won’t eat any fat, then there won’t be any to store”. Good logic! Wrong, but still logical. The problem is that some dietary fat has two functions. The first is the commonly understood function of providing all that energy you don’t need (else why would you be reading a diet book? ). The second is as a provider of essential fatty acids (EFAs), which are vital to you for other things than energy.

If you’ve been eating the wrong kinds of fat for a long time, it is very possible for you to have a huge surplus of bodyfat and a serious deficit of EFAs—at the same time. And this means that The Beast will be wide-awake trying (in its clumsy, brutish way) to force you to eat more food in order to get more EFAs.

In other words, by itself, simpleminded low-fat dieting won't work. Instead you must learn to get the right kinds of fat in the right amounts and no more than that. As we discussed in Part One, this is not difficult once you know how. There is also some other good news about getting rid of fat.

As I mentioned above, the muscles in particular “prefer” to use fat for fuel, rather than carbohydrate (or protein). And fat is exactly what they will use—unless they are forced to do otherwise. This is great news for dieters because muscles are what power the heart, breathing, and all other body movement twenty-four hours a day. That takes a lot of energy, which can use up a lot of fat—if we avoid doing foolish and ignorant things that interfere with this fabulous fat-fighting function.

There are two things that do interfere—dramatically—with the normal fat burning process.

1.    Hard, fast, aerobic exercise slows fat burning because it forces the muscles to switch over to using carbohydrate (glycogen) as a fuel source. This probably happens because intense exercise uses energy faster than it can be delivered to the muscles by fat delivery systems, so the muscles must begin to use your limited store of glycogen (the stored form of carbohydrate) to maintain the pace.

2.    Too much dietary carbohydrate (or dietary carbohydrate of the wrong type) suppresses fat burning because of the particular “preference” your body has for handling carbohydrate. (We discuss this in carbohydrate is for burning.)

Hard, fast exercise that forces the muscles to switch over to burning glycogen (stored carbohydrate) is a bad idea for dieters. Obviously, fat is what we want to burn and “glycogen ain’t fat”. But there is also another reason. Your body can’t store very much glycogen—so hard exercise will use it up very quickly. This creates an “insufficiency” of glycogen that wakes up The Beast, which now wants you to eat to replace the glycogen. The glycogen must be replaced because your brain, nervous system, and blood cells need it for energy and they get very unhappy when they don’t have the energy they need. The switchover from fat to carbohydrate happens when you exercise at a rate that forces you up to between 55% and 65% of your “VO2 max” or higher. (You will find the discussion of this term and techniques for managing it in more on… exercise.)

On the other hand, slow, steady exercise that stays below the approximately 60% switchover point (walking, slow jogging, etc.) is very good for dieters because the muscles are burning mostly fat and the fat cells are probably having no trouble sending it to them fast enough.