Posted on March 19, 2008, 9:14 a.m. in Hormones & Pharmacological Agents
Melatonin, a hormone made by the pineal gland, affects many organs including the thymus, the pituitary, and the hypothalamus. Melatonin plays a major role in setting the body’s internal clock. Blind people use melatonin to improve their ability to sleep and to regulate their circadian cycle. It is also used to combat jet lag. Studies on mice suggest that melatonin may play an important role in increasing lifespan.
ROLE FOR ANTI-AGING:
Melatonin’s anti-aging benefits may include improved sleep rhythms, improved strength of the immune system, more positive response to stress and enhanced wellbeing. A 1987 study conducted by Walter Pierpaoli, M.D. and George J. M. Maestroni, M.D. found that mice who received melatonin in their drinking water at night lived 20% longer than untreated mice. Studies show that the effects of melatonin depend greatly on the age of the patient and the timing of the dosage in the sleep-wake cycle. A study published by the British Journal of Cancer in 2001 revealed that the incidence of breast cancer in women who had become blind before the age of 65 was 49% lower than that in normally sighted women. Researchers believe that these findings are proof that high levels of melatonin help to protect against breast cancer. More recently, results of a study in chickens found that those given a daily dose of melatonin had higher white blood cell (WBC) counts and showed significantly higher T- and B-lymphocyte proliferation. Thus suggesting that melatonin strengthens the immune system by increasing the number of circulating WBC’s and boosting the activity of both B and T-cells.
Insomnia and/or frequent waking are symptoms of melatonin deficiency.
THERAPEUTIC DAILY AMOUNT:
Melatonin is widely available in drug-store chains in both capsules and in slow-release preparations. Therapeutic doses range from 0.5-5mg per day.
MAXIMUM SAFE LEVEL:
A safety study carried out in 2000 found that a dose of 10 mg of melatonin daily produced no toxic effects when given to 40 healthy males for a period of 28 days. However, this does not mean that a similar dose of the hormone is safe for chronic use.
Melatonin causes sleepiness, so it should be taken only at bedtime. At higher doses, however, it may cause increases in depression and psychosis in patients already suffering from them. Women seeking to become pregnant, women already pregnant, children, people suffering from cancer, Hodgkin’s disease, leukemia, lymphoma, and multiple myeloma should not take melatonin supplements.
It is advised that patients with prostate cancer do not take more than 3 mg of melatonin per night.