Metabolism is a series of chemical reactions in the body that allow the body to grow, reproduce, maintain their structure, and respond to their environments. It is the rate at which the human body burns fat and is the key variable in weight control and weight loss. The speed of metabolism varies greatly from person to person and numerous factors come into account.

For many people the reason for being thin is strictly a cosmetic one. It is perceived as healthy and fits into the cultural context of what is considered attractive. But there are better reasons to avoid being overweight. Being obese puts you at a serious risk of developing disease. Staying within healthy parameters will diminish your risk and can help you feel better emotionally and physically. That’s not to say that you should be out starving yourself in order to achieve an acceptable weight, but is worth knowing where you stand in relation to body mass and risk factors.