Melatonin is a hormone your brain creates naturally. It is also found in St John’s wort, a common herbal supplement for depression. It is available for purchase over-the-counter and is recommended to normalize sleep patterns. Melatonin is an antioxidant and helps strengthen the immune system.
As you get older, your melatonin levels decrease, which might explain why adults go to bed earlier than when they were younger. Decreased melatonin can cause insomnia and other sleep disturbances. Melatonin also lowers body temperature.
There is a question about whether or not melatonin increases or decreases depression. Melatonin is produced from serotonin, a neurotransmitter commonly linked to mood. Supplemental melatonin, preferably at night since it causes drowsiness, may help treat mild depression. Low doses (10mg or less) seems to be safe for most people.
Too much melatonin can cause increased sleepiness, headaches, and to a lesser extent, mild irritability, anxiety and depression. Other side effects includes vivid dreams and stomach problems. Melatonin is only recommended for short-term or sporadic use.
As usual, please check with your doctor before taking melatonin.
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