Sports Research L-Theanine 200 mg with Suntheanine, 60 softgels
4.6(15,416)
$19.95
The dose used in the 4-week sleep trial.
Buy on AmazonAmazon price on Sep 18, 2026.
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Products that match the form and dose used in the studies. Umbral earns a commission on some purchases; the order never changes because of it.
Moderate
200 mg
Ratings, prices and photos were read from Amazon on Sep 18, 2026. Amazon prices change; the current one is on the product page.
As an Amazon Associate, Umbral earns from qualifying purchases. Product data is provided by Amazon and may change; ratings and prices shown are Amazon’s, not Umbral’s. Recommendations are based on the evidence grade and the form used in trials, never on commission.
Sports Research L-Theanine + Caffeine Nootropic Supplement
4.5(3,677)
$22.95
The classic pairing: theanine takes the edge off caffeine's jitter without cancelling the alertness. Only useful if you are already taking caffeine — otherwise take theanine alone.
Buy on AmazonAmazon price on Sep 18, 2026.
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See all on AmazonWhat to look for
- ✓200 mg per capsule
- ✓Suntheanine® or ≥98% pure L-theanine
What to avoid
- ✕Blends with high caffeine if you want it for sleep
Safety notes
- · Very safe; additive with antihypertensives.
As an Amazon Associate, Umbral earns from qualifying purchases. Product data comes from Amazon and may change; ratings and prices are Amazon's, not Umbral's. Suggestions are based on the science and the form used in studies, never on commission.
Umbral is a wellness product, not a medical device. It does not diagnose, treat, cure or prevent any disease. Supplement information is educational; talk to a clinician before starting anything, especially if you are pregnant, under 18, managing a condition or taking medication.
These statements have not been evaluated by the Food and Drug Administration.