Creatine, an amino acid that is produced in minute amounts by the liver, kidneys, and pancreas, helps muscles replenish adenosine triphosphate, which fuels muscle contraction. The daily creatine requirement for a human is 2 grams, most of which is supplied by eating fish or red meat. Synthetic creatine, a relatively simple mixture of water and the salts cyanamide and sarcosine, was first made by an American pharmaceutical company in the late 1950s. By the 1980s, Eastern bloc countries had been using it, with anabolic steroids, for over a decade. Tubs of the powder, a chalky substance that can be mixed with liquids, started hitting American stores in the early '90s.
Creatine helps weightlifters and runners squeeze in extra reps or stair climbs.
That translates into added brawn and bulk. The weight gains can be startling. It is not uncommon for users taking the 10-gram recommended daily dose to gain 20 to 30 pounds in a few months. Little wonder, given that a pound of creatine equals the amount of protein in 100 pounds of red meat. However, no studies have measured creatine's effects for more than three months, and most of those have been financed by supplement-manufacturing companies.