Sleep and Anti-Aging Properties of Melatonin Supplements
Some experts recommend melatonin as a first-line agent to treat insomnia in older adults. The World Sleep Society disagrees due to its low efficacy. Subjectively, people report better sleep, though objectively a meta-analysis of studies found that melatonin only helped people get to sleep 4 minutes faster and extend overall sleep duration by about 13 minutes.
If you do want to try melatonin to help with sleep, older adults are advised to use the smallest effective dose an hour before bedtime, starting perhaps at 0.3 mg. The 12 mg supplements on the market could produce levels in the bloodstream that can be two hundred times higher than normal nightly levels, which raises safety concerns. After all, melatonin used to be known as the anti-gonad hormone, with human-equivalent doses of just a milligram or two reducing the size of sex organs and impairing fertility in laboratory animals.
Furthermore, due to poor regulation of dietary supplements, in the U.S. you never know what you’re going to get. An analysis of thirty-one different brands of melatonin supplements found that the actual melatonin content varied up to nearly 500 percent compared to what was listed on the bottle. Even within a single brand, different lots of the same product suffered similar variability. Given that there is no guarantee of the strength or purity of melatonin supplements, many countries have banned over-the-counter melatonin, making it prescription-only so the authenticity could be ensured. U.S. citizens can get certified melatonin by sending a prescription to an online Canadian pharmacy (though it’s technically illegal) or can get melatonin from their diet.
Interestingly, the rise in melatonin blood levels or metabolites in the urine consistently exceed the amount of melatonin that’s actually ingested in these foods. You can even get a spike in melatonin by eating fruit that doesn’t even appear to have any detectable melatonin at all. The answer to the puzzle may lie in the gut.
The first site outside the pineal gland where melatonin production was discovered was the human appendix. Although we now know melatonin can be produced throughout the body, the greatest accumulation appears to be in the gastrointestinal tract, estimated to contain more than 400 times more melatonin than the pineal gland. So, perhaps the consumption of certain foods can cause the release of some of this bounty into the bloodstream. This may be how magnesium supplements (500 mg a day for eight weeks) were able to improve sleep quality and quantity over placebo, given the effect was accompanied by a rise in melatonin levels.
What’s more intriguing are its purported anti-aging benefits. In addition to regulating sleep and our circadian rhythms (when properly timed it can be used to treat jet lag), melatonin can have antioxidant and anti-inflammatory properties. However, secretion of melatonin appears to progressively decline with age, dropping as much as 70 percent between middle and older age. This has led some to speculate that “aging is a syndrome of relative melatonin deficiency resulting from the gradual failure of the pineal gland.”
A variety of age-related diseases such as Alzheimer’s are associated with particularly low levels of melatonin, but we have yet to determine if this is a cause or consequence of disease. Melatonin supplementation extends the lifespan of fruit flies but shortens the lifespan of C. elegans. Mice after having their pineal glands removed appeared to age more rapidly, but when put to the test, melatonin prolonged survival of some strains of mice, but shortened the lives of others (by inducing cancer). So, are we more like New Zealand bIack mice or Bagg albino mice? Sometimes the same research group went on to publish opposite results, showing melatonin both increasing and decreasing lifespan. Not surprisingly, a meta-analysis found no overall effect when all of the mouse studies were considered together. In rats, melatonin significantly improved survival, but so did a melatonin-blocking drug.
Some experts recommend melatonin as a first-line agent to treat insomnia in older adults. The World Sleep Society disagrees due to its low efficacy. Subjectively, people report better sleep, though objectively a meta-analysis of studies found that melatonin only helped people get to sleep 4 minutes faster and extend overall sleep duration by about 13 minutes.
If you do want to try melatonin to help with sleep, older adults are advised to use the smallest effective dose an hour before bedtime, starting perhaps at 0.3 mg. The 12 mg supplements on the market could produce levels in the bloodstream that can be two hundred times higher than normal nightly levels, which raises safety concerns. After all, melatonin used to be known as the anti-gonad hormone, with human-equivalent doses of just a milligram or two reducing the size of sex organs and impairing fertility in laboratory animals.
Furthermore, due to poor regulation of dietary supplements, in the U.S. you never know what you’re going to get. An analysis of thirty-one different brands of melatonin supplements found that the actual melatonin content varied up to nearly 500 percent compared to what was listed on the bottle. Even within a single brand, different lots of the same product suffered similar variability. Given that there is no guarantee of the strength or purity of melatonin supplements, many countries have banned over-the-counter melatonin, making it prescription-only so the authenticity could be ensured. U.S. citizens can get certified melatonin by sending a prescription to an online Canadian pharmacy (though it’s technically illegal) or can get melatonin from their diet.
Interestingly, the rise in melatonin blood levels or metabolites in the urine consistently exceed the amount of melatonin that’s actually ingested in these foods. You can even get a spike in melatonin by eating fruit that doesn’t even appear to have any detectable melatonin at all. The answer to the puzzle may lie in the gut.
The first site outside the pineal gland where melatonin production was discovered was the human appendix. Although we now know melatonin can be produced throughout the body, the greatest accumulation appears to be in the gastrointestinal tract, estimated to contain more than 400 times more melatonin than the pineal gland. So, perhaps the consumption of certain foods can cause the release of some of this bounty into the bloodstream. This may be how magnesium supplements (500 mg a day for eight weeks) were able to improve sleep quality and quantity over placebo, given the effect was accompanied by a rise in melatonin levels.
What’s more intriguing are its purported anti-aging benefits. In addition to regulating sleep and our circadian rhythms (when properly timed it can be used to treat jet lag), melatonin can have antioxidant and anti-inflammatory properties. However, secretion of melatonin appears to progressively decline with age, dropping as much as 70 percent between middle and older age. This has led some to speculate that “aging is a syndrome of relative melatonin deficiency resulting from the gradual failure of the pineal gland.”
A variety of age-related diseases such as Alzheimer’s are associated with particularly low levels of melatonin, but we have yet to determine if this is a cause or consequence of disease. Melatonin supplementation extends the lifespan of fruit flies but shortens the lifespan of C. elegans. Mice after having their pineal glands removed appeared to age more rapidly, but when put to the test, melatonin prolonged survival of some strains of mice, but shortened the lives of others (by inducing cancer). So, are we more like New Zealand bIack mice or Bagg albino mice? Sometimes the same research group went on to publish opposite results, showing melatonin both increasing and decreasing lifespan. Not surprisingly, a meta-analysis found no overall effect when all of the mouse studies were considered together. In rats, melatonin significantly improved survival, but so did a melatonin-blocking drug.
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