You're getting 300mg of **Magnesium** as citrate — solidly within the 100–400mg clinical range and enough to support muscle relaxation, stress reduction, and sleep quality. The powder format dissolves in water for easy absorption, and citrate is a well-absorbed form, though it can have a mild laxative effect at higher doses.

The formula adds **L-Theanine** and **GABA** at 100mg each. L-Theanine promotes calm without drowsiness, but the most-studied single dose for relaxation is 200mg — so you're getting half of that. GABA's ability to cross the blood-brain barrier when taken orally is still debated in the research, and the clinical evidence for supplemental GABA remains limited.

The magnesium dose is the real strength here. If you're taking this primarily for relaxation or sleep, the L-Theanine is a nice addition but falls short of the dose used in most studies — you'd get more from it at 200mg.

BioStacks
youtheory

Relax Magnesium Powder Berry

Powder · 6 Gram · 21 servings · $0.91/serving

iHerbAmazon

Best for

Stress & MoodSleep

Ingredients (3)

Magnesium

100%

Dose

300 mg

Target

100–400 mg

Form

Standard

L-Theanine

100%

Dose

100 mg

Target

100–250 mg

Form

—

GABA

100%

Dose

100 mg

Target

100–300 mg

Form

—

Other Ingredients (4)

XylitolSweetener

A FODMAP sugar alcohol that can cause GI distress (bloating, gas, diarrhea) at moderate doses (>10-20g/day), though supplement amounts are typically small. Extremely toxic to dogs — households with pets should store securely.

Natural FlavorsFlavor

Broad regulatory category of flavor constituents derived from natural sources. Composition is proprietary and not disclosed — 'Natural Flavors' can include several hundred different compounds depending on the target flavor profile, including hexane-extracted constituents and proprietary carrier solvents. 'Natural' is a regulatory definition (21 CFR §101.22), not a safety guarantee.

GlycineAmino Acid

Non-essential amino acid; smallest of the 20 proteinogenic amino acids. Mildly sweet taste — sometimes used as a low-glycemic flavor modifier in addition to its bioactive role

Stevia ExtractSweetener

Zero-calorie natural sweetener extracted from the leaves of Stevia rebaudiana

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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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