BioStacks
NFH

L-Theanine SAP

1 Capsule · 60 servings · $0.23/serving

iHerbAmazon

Best for

Stress & MoodSleep

Ingredients (1)

L-Theanine

100%

Dose

250 mg

Target

100–250 mg

Form

—

Other Ingredients (5)

CarboxymethylcelluloseThickener

Carboxymethylcellulose was the second emulsifier (with polysorbate 80) in Chassaing et al. 2015 (Nature, PMID 25731162), which showed mucus-barrier thinning, a microbiota shift toward pro-inflammatory species, low-grade inflammation, and metabolic syndrome in mice. Chassaing 2022 (Gastroenterology, PMID 34774538) tested CMC directly in a randomized controlled human feeding trial and found reduced microbial diversity and bacterial encroachment into the normally sterile mucus layer in a susceptible subset of participants. EFSA's 2018 re-evaluation could not establish a safe level due to data gaps. For a purely textural excipient, the gut-barrier risk profile is unfavorable when safer thickeners are widely available.

Silicon DioxideAnti-caking

Fine silica powder used to prevent clumping

Magnesium StearateLubricant

A salt of stearic acid used as a lubricant in tablet and capsule production

Microcrystalline CelluloseBinder

Plant-derived cellulose used as a binder and filler in supplements

Purified WaterSolvent

Water meeting USP specifications used as solvent/vehicle in gummies and liquids

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

Adults: Take 1 capsule daily or as directed by your healthcare practitioner.

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

Price Check

$13.86

$10$20$50

Cheaper than 82% of 122 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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