Melatonin is an extraordinary hormone that helps to control our sleep-wake cycles. Obviously, the most prominent side effect of melatonin is that it makes you sleepy. This is why you should never take it during your daytime hours, as it can screw up your rhythm and seriously mess up your day. That said, it does host a slew of additional side effects — some positive and some negative.
Melatonin and Blood Sugar
Even low doses of melatonin have been shown to drastically reduce glucose tolerance and insulin sensitivity in individuals suffering from type 1 diabetes. Diabetics should therefore not consume it as a supplement. Inversely, researchers found that non-diabetic people with low levels of melatonin in their body were twice as likely to develop diabetes 1.
Melatonin and Blood Pressure
Research conducted in 2004 by Harvard Medical School suggests that prolonged, consistent consumption of melatonin can lower blood pressure in people suffering from hypertension. It has also been shown to increase good cholesterol (HDL) and lower bad cholesterol (LDL). Individuals who are at risk of cardiovascular disease and/or take blood pressure medication should not consume it 2.
Melatonin and Reproduction
There is a lot of conflicting data regarding melatonin and reproduction. Some studies suggest that it enhances fertility and pregnancy rates, but other studies show that it lowers the quantity of follice-stimulating hormones (FSH). The latter is responsible for managing the menstrual cycle. The general consensus at the moment is that you should avoid it altogether if you’re pregnant or trying to conceive.
Additional Side Effects Of Melatonin
Consuming too much it can lead to severe mood changes and even outright depression. Some people have even reported experiencing delusion and hallucinations on it, though this is extraordinarily rare.
Individuals on antipsychotic medications should never consume it. Some doctors also recommend not using it if you’re on antidepressant medications as well, but I take Paxil everyday and have experienced no problems with melatonin.
Consumption of far too high doses of it (10 mg and beyond) can cause drowsiness, irritability and grogginess. It’s generally advised that you stick to lower doses between 3 mg and 5 mg. Some even go as low as .3 mg.
Overall, melatonin is fairly safe for most people to consume. More research regarding the side effects of melatonin is obviously needed, but plenty of people (including me) use it without any problems. That said, if you’re pregnant or suffer from cardiovascular issues, then you should speak to your physician before consuming it.