BioStacks
Swanson

Ultimate Respiratory Defense

1 Capsule · 60 servings · $0.53/serving

iHerbAmazon

Best for

Liver

Ingredients (2)

N-Acetyl Cysteine (NAC)

100%

Dose

600 mg

Target

600–1800 mg

Form

—

Quercetin

50%

Dose

250 mg

Target

500–1000 mg

Form

—

Other Ingredients (4)

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.

Magnesium StearateLubricant

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

Silicon DioxideAnti-caking

Fine silica powder used to prevent clumping

HypromelloseCapsule

Plant-derived capsule material from cellulose

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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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