Can melatonin extend lifespan?

Health experts are now seriously studying the possibility of the potential benefit of the natural sleep-enhancing food supplement melatonin in extending lifespan.

In test-tube and animal experiments, researchers have found that melatonin protects cells, strengthens the immune system, slows the growth of some tumors, and protects the heart and blood vessels.

Tests with laboratory mice suggest that melatonin might also reduce the effects of aging and enhance sexual function, but scientists caution that these results are very preliminary and still not conclusive.

Experts agree, though, that the preliminary findings are exciting and promising.

Regarding the question if melatonin can extend lifespan, melatonin, in tests on both rats and mice, caused a significant 20 percent increase in their lifespan. There are, however, no human studies to support this contention, but if a similar effect is present in humans, this could translate into an additional 10 to 14 years of additional lifespan.

Experts believe that if melatonin does allow one to live longer and healthier, it is likely due to melatonin’s benefit of reducing free radical damage, stimulating an aging immune system, protecting the cardiovascular system, preserving a youthful circadian rhythm, and stimulating the production of growth hormone.

Aside from melatonin’s potential anti-aging effects, a 1995 rodent study suggests that taking small amounts of melatonin on a regular basis may prevent the age-related decline in testosterone levels, allowing men to be more active sexually in their later years.

In a research published in the prestigious Lancet journal by scientists at the Institute for Cardiovascular Diagnosis and Therapy in Salzburg, Austria, the findings suggest that melatonin also has a protective effect on the heart and blood vessels.

The scientists found that melatonin levels in the patients with coronary artery disease was five times lower than in healthy subjects.

They speculated that since melatonin reduces noradrenaline, which may inflict damage on arterial walls, the lack of melatonin in individuals with coronary heart disease fails to keep their noradrenaline levels in check.

In its feature on melatonin, Newsweek magazine labeled the food supplement as "the all-natural nightcap."

It is secreted by the pineal gland, a pea-sized structure at the center of the brain, and its secretion is stimulated by darkness at nighttime.

Melatonin secretion decreases as people get older. Scientists believe this may be the reason why older people have problems sleeping and they have shorter hours of sleep.

Studies suggest that melatonin supplements can help hasten sleep and ease jet lag, without the hazards or side effects of prescription sleeping pills.

Travelers and people suffering from mild sleep disorders and who lack energy because of lack of sleep or poor quality of sleep may benefit the most from melatonin supplementation. According to the Newsweek article, a typical comment from discussion groups on the Internet is, "Folks, I have tried it and it’s great. It has... restored my sleep cycle, given me lots of energy."

According to Francis Melegrito, marketing director of Trianon International which distributes Melatonin-T capsules locally, although melatonin has been shown to be safe in past studies even if taken in big doses, women who are pregnant or nursing, and people with severe allergies or autoimmune diseases should not take it.

Women trying to conceive should also think twice about taking the hormone, since high doses (25 to 30 times the usual dose) can act as a contraceptive.

For those with any concomitant medical condition should consult their physician first before taking melatonin.

Trianon Melatonin-T in 3-mg capsules is available as an over-the-counter supplement in Mercury, Watson and other leading drug stores nationwide.

The usual dose is one capsule daily before bedtime for sustained long-lasting effect. The brand has received several awards locally for marketing excellence.