Melatonin is the most widely used sleep supplement, and for most people with occasional trouble falling asleep, a low dose taken one to two hours before bed is a reasonable starting point. But melatonin is far from the only option. Several other supplements, foods, and over-the-counter products can help with sleep, each working through different mechanisms and suited to different problems.
Melatonin
Melatonin is a hormone your brain naturally produces as it gets dark, signaling your body that it’s time to wind down. Taking it as a supplement works best when your internal clock is out of sync, whether from jet lag, shift work, or a sleep schedule that’s drifted later than you’d like. It’s less effective as a sedative and more effective as a timing tool.
For short-term sleep problems, the NHS recommends a 2mg slow-release tablet taken one to two hours before bedtime. For persistent insomnia, the same 2mg starting dose is taken 30 minutes to one hour before bed, with the option to gradually increase up to 10mg if needed. Most sleep researchers suggest starting at the lowest dose that works, since more isn’t necessarily better. Common side effects include headache, dizziness, nausea, and next-day drowsiness. That last one matters: avoid driving or operating machinery within five hours of taking it. Less common effects include mild anxiety, confusion, and short-lived feelings of depression.
Magnesium
Magnesium plays a role in several brain pathways that regulate relaxation and sleepiness, including those involving GABA (your brain’s main calming signal), cortisol (a stress hormone), and melatonin itself. Many people are mildly deficient in magnesium without knowing it, and correcting that shortfall can improve sleep quality even without changing anything else.
The form matters. Magnesium glycinate and magnesium bisglycinate are most commonly recommended for sleep because they’re well absorbed and less likely to cause digestive issues than magnesium oxide or citrate. The Sleep Foundation recommends capping supplemental magnesium at 350mg per day to avoid side effects like loose stools and stomach cramps. Taking it about 30 to 60 minutes before bed is a common approach. Magnesium is one of the gentler options on this list, and many people combine it with melatonin without issues.
L-Theanine
L-theanine is an amino acid found naturally in tea leaves. It doesn’t knock you out. Instead, it promotes a calm, alert state that makes it easier to transition into sleep. It works partly by boosting calming brain activity and reducing the mental chatter that keeps people staring at the ceiling.
Clinical studies typically use doses between 100 and 400mg per day. Many people find that 200mg taken in the evening hits the sweet spot: enough to feel noticeably more relaxed without any morning grogginess. It’s one of the better-tolerated sleep supplements, with very few reported side effects, and it can be useful for people whose main sleep problem is an overactive mind rather than a broken body clock.
Glycine
Glycine is another amino acid, this one found in bone broth, meat, and collagen-rich foods. Research suggests it helps with sleep by lowering core body temperature, which mimics the natural cooling your body does as you drift off. It also appears to increase serotonin levels in the brain, which plays a role in sleep regulation.
The dose used in human studies is 3 grams, taken before bed. At that amount, researchers found no side effects. Glycine is particularly interesting for people who feel like they sleep long enough but never wake up feeling rested, since some evidence points to improvements in sleep quality and next-day alertness rather than just faster sleep onset.
Valerian Root
Valerian is a flowering plant that’s been used as a sleep remedy for centuries. Multiple studies suggest it can reduce the time it takes to fall asleep and improve overall sleep quality. The challenge is that dosages have varied widely across studies, and the research hasn’t pinpointed the most effective amount or how long you need to take it before seeing results.
Most supplements contain 300 to 600mg of valerian extract, taken 30 minutes to two hours before bed. Many people notice a mild, calming effect within the first few nights, but some need a week or two of consistent use. Valerian has an earthy, somewhat unpleasant smell, which is normal. It’s generally well tolerated, though it can occasionally cause headaches or digestive upset.
Tart Cherry Juice
Tart cherry juice is one of the few food-based sleep aids with some research behind it. Montmorency tart cherries contain more than six times the melatonin of other tart cherry varieties, which partly explains the effect. Small studies suggest that drinking tart cherry juice can improve both sleep duration and sleep quality, particularly in people with insomnia.
The typical approach in studies is 8 ounces of tart cherry juice in the morning and another 8 ounces in the evening, one to two hours before bed. It’s a gentle option and a good fit for people who’d rather not take pills, though the sugar content is worth considering if you’re watching your intake. Look for 100% tart cherry juice concentrate rather than cherry-flavored blends.
Over-the-Counter Antihistamines
Many drugstore sleep aids rely on older antihistamines, the same ingredients found in allergy medications, to cause drowsiness as a side effect. These products work in the short term, but they come with real limitations. Your body builds tolerance quickly, meaning they stop working after a few nights of regular use. They can also amplify the effects of alcohol or other medications.
Harvard sleep expert Dr. Lawrence Epstein notes these products are acceptable for an occasional bad night but aren’t meant for ongoing use. For older adults especially, antihistamine-based sleep aids carry risks of confusion and falls. There’s also limited long-term safety data. If you find yourself reaching for them more than a couple of nights a week, a different approach is worth exploring.
CBD
CBD has gained enormous popularity as a sleep aid, but the clinical evidence is surprisingly thin. A randomized, placebo-controlled trial testing 50mg and 100mg daily doses of CBD over eight weeks found no significant improvement in insomnia symptoms compared to placebo. That doesn’t mean CBD does nothing for anyone. Some people report that it helps with anxiety, which can indirectly improve sleep. But at the doses commonly sold in consumer products, the direct sleep-promoting effect hasn’t held up in rigorous testing.
Choosing the Right Option
The best choice depends on why you’re not sleeping well. If your problem is falling asleep at the right time, melatonin addresses the root cause most directly. If you lie awake with a racing mind, L-theanine or magnesium targets that mental restlessness. If you fall asleep fine but wake up feeling unrested, glycine may improve the quality of the sleep you’re already getting.
Combining a couple of these is common and generally safe. Magnesium plus melatonin is one of the most popular pairings. L-theanine and magnesium also complement each other well, since they work through different pathways. Start with one supplement at a time so you can tell what’s actually helping, and give each option at least a week before deciding it isn’t working. Sleep supplements tend to have subtler effects than prescription medications, so the improvements may be gradual rather than dramatic.