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Sleep is an important activity to all of us. It allows the body to repair its
tissues, rejuvenate other body parts and revitalize the brain. It gets us ready for the next day.
Why we sleep at night is linked to pineal gland, a pea-sized gland located in the
brain. It secretes a neurohormone melatonin. At day the pineal gland is inactive,
but at night it secretes high levels of melatonin, which makes sleep all the more
inviting to all of us.
Because of its involvement in the body's circadian rhythm, consumers
are driven to think of it as a sleep inducer, especially when attacked
by insomnia or jet lag.
Just how effective it is in curing insomnia has been a subject of many scientific
studies, and results so far are mixed. Some have shown positive
findings, but most had significant limitations, like the duration of
the studies or lack of female
participants.
If you have insomnia, it is recommended to know its underlying cause.
Modifications to present lifestyle and sleeping environment also help,
as some factors when changed or eliminated have shown to bring improved
quality of sleep to some people for a long time.
Another notion worth of attention here is the levels of melatonin in old people
compared to those in younger people. Many elders have trouble falling
asleep, and it is attributed to their declining melatonin levels.
However, a recent study had cast doubt on the popular notion that
melatonin levels actually go down as people age.
A team consisting of Dr. Charles Czeisler, M.D., Ph.D. and his
colleagues at Harvard Medical School and Brigham and Women's Hospital
studied 34 healthy elders, male and female, free from sleep disorders
and medications ranging from 65-81 years of age, by comparing their
nighttime melatonin levels with those from 98 younger men aged 18-30.
By taking and analyzing their blood samples, they discovered that the melatonin
levels of the older group had no significant difference from those belonging to the younger group.
"The idea that a pineal aging clock winds down as you get older is
simply not true," says Jamie Zeitzer, Ph.D. "Being older does not cause
a person to have low melatonin levels. While we know that some older
individuals have low melatonin levels, it isn't because of their age
per se."
However, melatonin as a supplement seems promising in fighting jet lag and in
promoting daytime sleepiness.
Dr. James K. Wyatt of Rush University Medical Center and his colleagues
at Harvard Medical School assigned a group of people free from sleep
disorders to be put on a 20-hour sleep-wake schedule, simulating a
traveller crossing four time zones eastward every day. They were asked
to take 0.3 or 5 mg of melatonin or a look-alike placebo pill 30
minutes before each scheduled sleep period, which lasted for 7 hours.
People who took melatonin had longer sleep time during the day when the
body doesn't normally produce it, compared to those who took placebo,
the study found out. But when they were given melatonin at night when
the body produces its own melatonin, no added benefits were discovered.
Also, melatonin as a supplement seems to lift winter depression by resetting the
circadian rhythms in people affected by Seasonal Affective Disorder (SAD).
The researchers assigned 68 SAD patients to take either low doses of
melatonin or placebo in the morning or afternoon for one winter month.
Then they analyzed their sleep activity, melatonin rhythms, and
depression symptoms. The researchers had found out that melatonin had
more antidepressant properties compared to placebo.
SAD happens when there is a delay in daily circadian rhythm due to the later winter dawn.
In addition to melatonin, getting enough morning sunlight works best to people with SAD.
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