Caffeine!

CaffeineCaffeine is a drug that is frequently used all over the world, usually for its stimulant effects. Caffeine increases alertness, lowers the perceived exertion of exercise and decreases reaction time. Caffeine has another effect on the body that few people know about. It also acts as a fat burner!

Caffeine works by increasing the rate of fatty acid metabolism, and decreasing the rate of carbohydrate (glucose) metabolism during aerobic exercise. Every study done on the effects of caffeine during aerobic exercise that has measured muscle glycogen levels, has found that glycogen is spared after ingestion of only 150 to 250 mg of caffeine. An increased reliance on fat, and decreased reliance on glucose and glycogen translates into increased aerobic exercise endurance and increased time to exhaustion. In addition to this, for a given amount of calories used during exercise, more calories will come from body fat if caffeine is consumed prior to exercise.

Caffeine does have side effects as well. At high doses (more than 15 mg/kg body weight), caffeine can produce slowed heart rate, hypertension, nervousness, irritability, insomnia, and gastrointestinal distress.  In addition to this, it is a diuretic that blocks the release of antidiuretic hormone. This causes the kidneys to excrete more fluid than normal, which can dehydrate the body.

Caffeine is one of the least marketed, but most effective “fat burners” available. It accomplishes what L-carnitine claims to do, but does not do. Caffeine will not help you lose weight on its own, but when taken before aerobic exercise, can increase fat burning and help you exercise longer by delaying the onset of fatigue. Caffeine will not have any beneficial effect on anaerobic exercise. If you use caffeine, please use it sparingly and in small doses. Be aware of the side effects listed above, and see a physician if you suspect any complications.