A dietary supplement (also known as food supplement) is a preparation intended to supply nutrients, (such as vitamins, minerals, fatty acids or amino acids) that are missing or not consumed in sufficient quantity in a person's diet. Some countries define dietary supplements as foods, whilst in others they are defined as drugs. In the United States, the definition of dietary supplements includes non-medicinal herbal supplements and hormones, such as DHEA, pregnenolone (both steroids) and melatonin. Supplements containing vitamins or dietary minerals are recognised by the Codex Alimentarius Commission (the United Nations' highest authority on food standards) as a category of food.