Carbohydrates or “carbs”, as most people refer to them these days, are the number one enemy to fat burning in most people’s diets. While it may seem more logical to limit fat in the diet when trying to get rid of fat, the body’s biochemical reaction to excess carbs will stop fat burning dead in its tracks. This is often how lose weight programs fail, because the importance of limiting carbohydrates is not stressed enough.
Carbohydrate intake blocks the body’s ability to burn fat because it triggers the production of the hormone insulin. Most people associate insulin with the disease diabetes and with blood sugar control, but it is also directly involved in the storage of fat in the body. Insulin stimulates the tissues to convert excess blood sugar and store as fat, and at the same time will block the conversion of fat back to sugar so it cannot be burned for energy.
When you consume a high carbohydrate meal, the carbs are rapidly digested and absorbed into the bloodstream as glucose, or “blood sugar”. A rise in blood glucose above what the body needs for its immediate energy needs triggers the release of insulin from the pancreas. Insulin stimulates the tissues of the body to store the extra blood sugar as glycogen (a quick energy supply stored in the liver and muscles) and as fat to be used later. The body’s capacity for glycogen storage is pretty small compared to the capacity for fat storage. This means that the more carbs you eat and the higher your blood sugar goes, the more fat you store.
A lot of dieters think that they can get away with eating carbs if they “make up for it” with extra exercise. That’s not the case at all. Although extra exercise will burn more calories, the effects of insulin are so strong, that the calorie burning will not be in the form of fat!
When you don’t eat a lot of carbs, and don’t produce a lot of insulin, exercise stimulates the body to first burn glycogen, and then turn to burning fat when the glycogen is gone. But, in the presence of high insulin, once the glycogen is used up, the insulin blocks the conversion of fat to blood sugar, so the body has to burn something else instead to get energy. That something else is protein from your muscles, not fat!
Initially, people who are trying to lose weight and continue to eat a lot of carbs may have the illusion that they are burning fat, but in actuality, they are losing water weight and muscle mass. The longer this continues, the harder it becomes to lose weight, because the reduction in muscle mass results in a slower metabolism. The end result is that the person who continues to eat a lot of carbs while trying to lose weight winds up weak and tired and with a higher percentage of body fat than before they began their weight loss program.
