The 5 Best Supplements for Better Sleep
Better sleep is the foundation of everything. These science-backed supplements help you fall asleep faster and wake up recovered.
Sleep Is Your Superpower
Alcohol destroys sleep quality. Even one drink reduces REM sleep by up to 24%. When you quit, your sleep improves — but the right supplements can accelerate that recovery. We are not talking about sleeping pills. These are natural, science-backed compounds that support your body's own sleep mechanisms.
What We Looked For
Every supplement on this list has peer-reviewed research supporting its effectiveness. We evaluated them on scientific evidence, quality of ingredients, third-party testing, and real-world results from our own 90-day testing period.
The Verdict
Magnesium Glycinate is the single best supplement for sleep — it is well-researched, affordable, and effective. L-Theanine is perfect for calming a racing mind. Ashwagandha (KSM-66) helps with both stress and sleep. ZMA combines zinc and magnesium for recovery-focused sleep, and Vitamin D3+K2 addresses a deficiency that affects most people and impacts sleep quality.
Our Top Picks
Magnesium Glycinate
Magnesium Glycinate is the most bioavailable form of magnesium for sleep. It promotes relaxation, reduces muscle tension, and supports GABA production — the neurotransmitter that calms your nervous system. This is the single supplement we recommend most.
Pros
- Most bioavailable magnesium form
- Promotes GABA production for calm
- Reduces muscle cramps and tension
- Well-researched with strong evidence
- Affordable at $15 for 120 tablets
Cons
- Large tablet size
- Takes 2-3 weeks for full effect
- May cause loose stools at high doses
L-Theanine
L-Theanine is an amino acid found in green tea that promotes alpha brain waves — the same waves produced during meditation. It reduces anxiety without drowsiness, making it perfect for calming a racing mind before bed.
Pros
- Promotes calming alpha brain waves
- No drowsiness or grogginess
- Works within 30-60 minutes
- Thorne is NSF-certified
- Can be stacked with magnesium
Cons
- Subtle effect — not a knockout
- Higher price for Thorne brand
- Some people feel no difference
KSM-66 Ashwagandha
KSM-66 is the most clinically studied ashwagandha extract. It reduces cortisol by up to 30%, improves sleep quality, and supports testosterone levels. The adaptogenic properties help your body handle stress more effectively.
Pros
- Reduces cortisol by up to 30%
- Supports testosterone levels
- Improves sleep onset and quality
- Most studied ashwagandha extract
- Dual stress and sleep benefits
Cons
- Takes 4-6 weeks for full effect
- Should cycle on and off
- May interact with thyroid medication
- Not recommended during pregnancy
Optimum Nutrition ZMA
ZMA combines zinc, magnesium aspartate, and vitamin B6 — three nutrients that many active men are deficient in. It supports deeper sleep, muscle recovery, and healthy testosterone production. Take it on an empty stomach before bed.
Pros
- Combines three essential nutrients
- Supports testosterone production
- Improves sleep depth
- Affordable from trusted brand
- Good for athletes with mineral depletion
Cons
- Must take on empty stomach
- Vivid dreams can be unsettling
- Zinc can cause nausea in some
- Magnesium form is not the best for sleep
K2 + D3
Most people are deficient in Vitamin D, and this deficiency directly impacts sleep quality. D3+K2 ensures proper calcium metabolism while supporting immune function, mood, and circadian rhythm regulation.
Pros
- Addresses widespread D3 deficiency
- K2 ensures proper calcium use
- Supports circadian rhythm
- Softgel form for easy absorption
- Third-party tested
Cons
- Effects take weeks to notice
- Requires fat for absorption
- Not a direct sleep supplement
- May need blood test to dose correctly
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