L-Theanine vs Magnesium for sleep
Short answer: For sleep, more users report improvement with Magnesium — 88% of 426 reports, versus 78% of 368 for L-Theanine.
L-Theanine has 18 meta-analyses and 78 randomized trials on PubMed; Magnesium has 82 and 210.
Based on 3,445 reports about L-Theanine and 2,377 about Magnesium. Not medical advice.
| L-Theanine Supplement | Magnesium Supplement | |
|---|---|---|
| User score | 54 | 50 |
| Verdict | Mostly positive | Mostly positive |
| Positive of reports that state an outcome | 65% | 73% |
| Reports | 3,445 | 2,377 |
| Research | AResearch: Strong | AResearch: Strong |
| Meta-analyses / RCTs | 18 / 78 | 82 / 210 |
| Mainly used for | ||
| Appetite % reporting improvement | 100% (2) | 67% (3) |
| Focus % reporting improvement | 88% (496) | 80% (45) |
| Energy % reporting improvement | 68% (97) | 75% (83) |
| Sleep % reporting improvement | 78% (368) | 88% (426) |
| Anxiety % reporting improvement | 91% (1278) | 90% (287) |
| Mood % reporting improvement | 77% (222) | 82% (116) |
| Memory % reporting improvement | 67% (12) | 100% (9) |
| Performance % reporting improvement | — | 88% (17) |
| Recovery % reporting improvement | — | 97% (32) |
| Pain & inflammation % reporting improvement | 100% (5) | 93% (43) |
| Digestion % reporting improvement | — | 82% (33) |
| Libido % reporting improvement | 25% (12) | 67% (15) |
| Hormones % reporting improvement | 50% (2) | 89% (27) |
| Blood sugar % reporting improvement | — | 100% (4) |
| Heart & lipids % reporting improvement | 88% (8) | 96% (26) |
| Skin & hair % reporting improvement | — | 100% (2) |
| Immunity % reporting improvement | 100% (2) | 88% (8) |
| Longevity % reporting improvement | — | 100% (3) |
| Common side effects | drowsiness, brain fog, vivid dreams, fatigue | diarrhea, drowsiness, stomach issues, vivid dreams |
| Typical dose reported | 200 mg / bedtime | daily |
This meta-analysis provides evidence that theanine plus caffeine, and theanine alone, could be beneficial for cognitive and mood outcomes. More research using tea beverages or tea-equivalent bioactive doses and research in free-living participants is needed.
Nutr Rev, 2025 ↗“This morning was my first time taking this combination along with my other daily vitamins and wow, what a difference it has made in my overall mood and anxiety!”
This review confirms that the quality of literature is substandard for physicians to make well-informed recommendations on usage of oral magnesium for older adults with insomnia. However, given that oral magnesium is very cheap and widely available, RCT evidence may support oral magnesium supplements (less than 1 g quantities given up to three times a day) for insomnia symptoms.
BMC Complement Med Ther, 2021 ↗“after supplementing with 400mg of Magnesium daily. Winter blues hit me hard and my multivitamin wasn't doing any justice, but once I began supplementing Magnesium, everything changed.”
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Percentages come from first-hand user reports and are not clinical outcomes. Talk to a doctor before starting, stopping or combining anything. How we rate