MANILA, Philippines ? Basking in the morning sunshine, avoiding exposure to artificial light at night while asleep could help facilitate the daily production of the natural hormone melatonin.

Melatonin (not to be confused with the vitamin supplement) is a natural hormone found in the body, and found in high levels in certain foods such as oats, corn, rice, ginger, tomatoes, banana and barley.

Melatonin, which helps keep insomnia at bay, appears to also slow the aging process, with particular probable effects such as being an antioxidant and an immune enhancer. It could also help in coping with stress, and may increase the ability to experience pleasure, as well as maintain a positive outlook and mood.

Dark environment

Optimal production of melatonin only occurs at night, however, and is dependent on a dark environment.

Doctor Neil Nedley, a doctor specializing in preventive medicine and the author of ?Proof Positive: How to Reliably Combat Disease and Achieve Optimal Health through Nutrition and Lifestyle,? who dedicated an entire chapter for melatonin in the book, cited the importance of avoiding light exposure at night while maximizing exposure to such during the daytime.

Nedley and ?Proof Positive? editor Dr. David De Rose also observed that the older we get, the less melatonin our body produces. ?Vigor declines as years advance, leaving less vitality with which to resist unhealthful influences, hence the greater necessity for the aged to have plenty of sunlight and fresh, pure air.?

Sleep before midnight

He added that sleep was worth far more before midnight than after midnight. ?Two hours of good sleep before twelve o? clock is worth more than four hours after twelve o?clock.?

Melatonin?which our body does not store but produces daily?can also be produced directly by the retina itself under conditions of darkness, with no involvement of the pineal gland, he added.

In an interview at Glaxo SmithKline?s press conference on insomnia, depression and other psychiatric disorders, Gerardo Carmelo B. Salazar, neurologist and psychiatrist, told Inquirer Science/Health that being active during the day and recuperating and resting at night is a natural sequence.

Melatonin maintains the body?s circadian rhythm, an internal 24-hour time-keeping system that plays a critical role in determining when we fall asleep and when we wake up, he said.

Insomnia sufferers

Meanwhile, the GSK press conference cited studies that 20 to 40 percent of adults have insomnia although only about a third of them seek treatment from doctors. And out of every five insomnia sufferers, two are found to have one or more psychiatric disorders as well. Generalized anxiety disorder, major depressive disorder and bipolar disorder are among the major psychiatric conditions associated with insomnia.

Dr. Paul V. Lee, associate professor of the UP College of Medicine, Department of Psychiatry and Behavioral Medicine, said in an Inquirer interview that melatonin?s benefits are nothing new, citing that melatonin has been used on some patients suffering from jet lag. Melatonin is even combined with certain antidepressants.

The natural production of melatonin is in the pineal gland (a tiny organ that is located in the exact center of the brain), Lee explained.

Nedley stressed that caffeine should be avoided because it stimulates the body?s hormone system (sympathetic nervous system) and tends to weaken melatonin production.

Caffeine can also cut melatonin production for six hours. Insomnia or disturbed sleep is usually the result, Nedley said.