A metabolic disorder occurs when abnormal chemical reactions in the body disrupt a proper metabolism. When this happens, there might be too much of some substances or too little of other ones which are needed to stay healthy. There are different groups of disorders. One group are the mitochondrial diseases, which affect the parts of the cells that produce the energy Another group affect the breakdown of amino acids, carbohydrates, or lipids. A metabolic disorder can develop, when some organs, such as liver or pancreas, become diseased or do not function normally. Diabetes is only one example.