← All brands · data verified 2026-07-08

21st Century

21st Century label-dose audit: 3 clinically dosed, 9 under clinical dose, 1 undisclosed — from NIH label data.

3 clinically dosed9 underdosed1 undisclosed

Ashwagandha (1)

21st Century — Ashwagandha Extract500 mg

Magnesium (12)

21st Century — 600+D3 plus Minerals Fruit Punch40 mg21st Century — Arthri-Flex Advantage + Vitamin D3200 mg21st Century — Calcium Magnesium Zinc + D3400 mg21st Century — CoraCal 1000 mg500 mg21st Century — Hair, Skin & Nails20 mg21st Century — ImmuBlast Citrus40 mg21st Century — Magnesium 250 mg250 mg21st Century — MgO-400483 mg21st Century — Sentry Adults50 mg21st Century — Sentry Energy40 mg21st Century — Sentry Senior50 mg21st Century — Sentry Senior Women's 50+100 mg

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