BioStacks
Nutricost

L-Theanine 200 mg

1 Capsule · 120 servings · $0.10/serving

iHerbAmazon

Best for

Stress & Mood

Ingredients (1)

L-Theanine

100%

Dose

200 mg

Target

100–250 mg

Form

—

Other Ingredients (2)

Rice FlourFiller

Rice-based ingredients carry risk of inorganic arsenic contamination (FDA and Consumer Reports). Rice accumulates arsenic from soil at higher rates than other grains. Used as a cheap filler — adds nothing beneficial.

GelatinCapsule

Protein derived from collagen, used in traditional capsule shells

How to Take It

Best taken in the evening

Calming — common before bed, or in the morning when paired with caffeine for focus.

With or without food

On the label

As a dietary supplement, take 1 capsule daily with 8-12 oz of water or as directed by your healthcare professional.

General guidance based on the ingredients, not a substitute for the label or your doctor.

Price Check

$11.95

$10$20$50

Cheaper than 88% of 101 theanine supplements

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Sources & Scoring

Nutrient data (RDA, UL, and safety thresholds) sourced from: NIH Office of Dietary Supplements and National Academies Dietary Reference Intakes (DRI).

This is not medical advice. Consult a healthcare provider before making changes to your supplement routine.

The score analyzes what's on the label: ingredient doses vs. clinical ranges, chemical forms, evidence levels, and known interactions. It does not verify label accuracy or test for contaminants — for that, look for third-party certifications like USP or NSF.

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