Melatonin, Dr. Reiter said, is a potent anti-oxidant. W hat seems most significant is that melatonin levels decline as people age, stripping their defenses against disease. Landmark discoveries about melatonin have been coming from Dr. Reiter's laboratory for years. He is credited with earlier findings that helped show how melatonin runs the body's clock for sleep, reproduction and moods. Synthetic melatonin has become a popular diet supplement in health food stores.
People take it for insomnia, jet lag and seasonal depression.
The U.S. Food and Drug Administration, meanwhile, is examining several prescription applications for melatonin. Melatonin is named for melanin, or skin pigment, and serotonin, a neurotransmitter found abundantly in the pineal gland. It was discovered by a Yale dermatologist who found that the extract from cow pineal glands lightened the skin of frogs. Melatonin later was identified as a hormone. Starting in 1992, Dr. Reiter's group produced evidence that melatonin neutralizes the body's most toxic free radical, the hydroxyl radical.