Supplement What is it What does it do Does it work? Any risks? Magnesium Mineral Decreases the amount of time it takes to fall asleep, and increases the quality and length of time that you sleep Yes. Magnesium supplements are very popular sleeping aids. Take no more than 400 mg. Too much magnesium may cause stomach upset or diarrhea. Melatonin Hormone Signals your brain that it is time to sleep Yes. Melatonin is a very popular sleeping aid. Consult with your physician before taking melatonin Antihistamine Sedative Causes drowsiness Yes. Sedatives are very effective methods of inducing drowsiness. Consult with your physician before taking antihistamines, especially if you are on other medication. You will quickly build up a tolerance, so be sure to only take sedatives once in a while. Valerian root Herb native to Europe and Asia Improves sleep quality Yes. Studies show that those who take valerian root benefit from better sleep quality. Short-term intake is safe for adults. However, safety remains uncertain for long-term use. Lavender Common plant Improves sleep quality and duration Unclear. Studies show improved sleep quality. However, more research is needed. Generally safe, though taking lavender supplements has been linked to nausea and stomach pain. Passion flower Flower native to North America, usually consumed as a tea Improves sleep quality Unclear. Studies are inconclusive. However, passion flower tea is safe to drink. Safe for adults. Glycine Amino acid. Can also be found in foods such as meat, eggs, spinach, kale, and bananas Improves sleep by lowering body temperature Yes. Studies show improved sleep quality when compared to placebo. Safe for adults. Tryptophan Amino acid Improves sleep quality and helps you fall asleep faster Unclear. Efficacy is not supported by strong scientific research. Unclear, as its use has not been extensively studied. Ginkgo biloba Natural herb Reduces stress and enhances relaxation Unclear. Efficacy is not supported by strong scientific research. Unclear, as its use has not been extensively studied. L-Theanine Amino acid Improves sleep and relaxation Unclear. Efficacy is not supported by strong scientific research. Unclear, as its use has not been extensively studied. Kava Plant native to the South Pacific islands, usually consumed as a tea Improves sleep quality Unclear. Efficacy is not supported by strong scientific research. Unsafe. Kava use has been linked to severe liver damage, and should be avoided.