The best supplements for sleep,
ranked by evidence.
The best supplements for sleep are rarely the loudest ones. Ranked by the evidence behind them, the list looks different: melatonin and glycine come out ahead, and magnesium, the internet's favorite, lands lower than you'd expect.
This guide covers 8 supplements with real sleep data: what each one does, the studied dose, and when to take it. Every evidence grade comes from the same catalog that powers the Suplagen app.
| Supplement | Evidence | Daily dose | When |
|---|---|---|---|
| Melatonin | moderate | 0.5-5 mg | Night |
| Glycine | moderate | 3-5 g | Night |
| Valerian Root | moderate | 300-600 mg | Night |
| L-Theanine | moderate | 100-400 mg | Morning, Night |
| Ashwagandha | moderate | 300-600 mg | Morning, Night |
| Magnesium Glycinate | limited | 100-350 mg elemental | Night |
| Apigenin | emerging | 50-100 mg | Night |
| Magnesium L-Threonate | emerging | 1000-2000 mg | Night |
The stack, ranked
0.5-5 mg · Night
Melatonin is a circadian signal rather than a sedative. It tells your brain the day is over, which is why it works best for jet lag and shifted schedules. Use the lowest dose that works, and treat it as a short-term tool; long-term nightly use is less studied.
3-5 g · Night
Glycine is the quiet overperformer here. 3 g about an hour before bed improved subjective sleep quality in trials, earning a moderate grade. It's cheap, tastes mildly sweet, and stays well tolerated even at the top of the range.
300-600 mg · Night
Valerian works on a delay. The trials showing better sleep quality run 2 to 4 weeks of consistent use, so judge it after a month, not a night. Don't drive after taking it, and know the strong smell is normal.
100-400 mg · Morning, Night
L-theanine helps you switch off without sedating you. The evidence for relaxed alertness is moderate, which makes it the pick when stress, not schedule, keeps you up. It works with or without food, any time of evening.
300-600 mg · Morning, Night
Ashwagandha earns its spot through stress. Moderate evidence supports lower cortisol and anxiety, and better sleep tends to ride along. Take it with food in the evening, and cycle it: 8 weeks on, 2 weeks off.
100-350 mg elemental · Night
Magnesium is the most recommended sleep supplement online, and the direct sleep evidence is honestly limited. It matters most when your intake runs low, which is common. Glycinate is the gentle evening form; keep supplemental magnesium at or under 350 mg elemental.
50-100 mg · Night
Apigenin is the chamomile compound, concentrated. The evidence is emerging and mostly extrapolated from chamomile research, so treat it as a supporting act. 50 to 100 mg before bed is gentle enough for nightly use.
1000-2000 mg · Night
Magnesium L-threonate is the brain-targeted form, and its dose (1,000 to 2,000 mg) refers to the compound, not elemental magnesium. For sleep specifically the evidence is emerging. If you already take glycinate, pick one form instead of stacking both.
How to combine them
Almost everything here times to the last hour before bed. Glycine goes about an hour out, valerian and apigenin 30 to 60 minutes, melatonin 30 to 90. L-theanine is flexible.
Two combinations need care. Valerian plus melatonin stacks sedation, so lower both doses if you combine them. And the two magnesium forms count toward one total, so pick one or track elemental magnesium closely.
The bigger sleep lever is what you do in the morning: caffeine within 6 to 8 hours of bedtime undoes most of this. If you take sedatives or sleep medication, clear this stack with your doctor first.
Common questions
Can you take magnesium and melatonin together?
Yes. They work through different mechanisms, and our catalog lists no interaction between them. If you'd rather start with one, magnesium vs melatonin breaks down which fits your situation.
Should you take melatonin every night?
The evidence is strongest for short-term and circadian use: jet lag, shift work, schedule resets. Long-term nightly use is less studied, so keep it intermittent and stay at the lowest effective dose unless a clinician directs otherwise.
How long before bed should you take sleep supplements?
Most of this stack works in a 30 to 90 minute window before bed: glycine about an hour out, valerian and apigenin 30 to 60 minutes, melatonin 30 to 90. Suplagen spaces these automatically once you set your sleep schedule.
Keep reading
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