NOW Supplements, NAC (N-Acetyl Cysteine) 600 mg with Selenium 100 Capsules Review
NOW NAC 600 mg with Selenium is offered as capsules, listed on this page at 250 capsules per bottle, with a 100 capsule size also available in the size selector. The product is presented under the headline benefits of free radical protection, the inclusion of selenium, and support for maintaining cellular health. The page explains that N-Acetyl Cysteine (NAC) is a stable form of the non-essential amino acid L-Cysteine. It is described as a sulfur-containing amino acid that acts as a stabilizer for the formation of protein structures and is also necessary for the formation of glutathione. Selenium is described as an essential trace mineral that facilitates the production of several important enzymes. The Supplement Facts panel lists a serving size of 1 capsule with 250 servings per container. Each serving provides 600 mg of N-Acetyl Cysteine (NAC), with no established Daily Value. The selenium content is listed as elemental selenium from 5 mg of L-Selenomethionine, providing 25 mcg per serving, which the page shows as 45% of the Daily Value. The suggested use is to take 1 capsule twice daily. The page carries a warning that the product is for adults only and advises consulting a physician if pregnant or nursing, taking medication, or having a medical condition. Other ingredients are hypromellose in a cellulose capsule, vegetable source stearic acid, citric acid and microcrystalline cellulose. The page states that the product is not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish, tree nut or sesame ingredients, and that it is produced in a GMP facility that processes other ingredients containing these allergens. Storage instructions say to keep the freshness packets in the bottle until it is empty, keep the bottle tightly closed between uses, and store it in a cool, dry place after opening. The page states that the product is made and quality tested in the USA with globally sourced ingredients. The bottle is made from 100% post-consumer recycled resin. The page notes that natural color variation may occur when the product is exposed to air and that speckling in the capsule may occur without affecting product quality. Listed badges include Kosher, Non-GMO, Halal, and Dairy Free, along with a 100% Money-Back Guarantee. The page offers a one-time purchase at $29.99 or subscription delivery options ranging from every 30 days to every 120 days, with subscription orders over $35 shipping free. The listed price works out to $0.12 per serving. The page also carries the statement that these statements have not been evaluated by the Food and Drug Administration and that the product is not intended to diagnose, treat, cure, or prevent any disease.
Study, Trial or Testing Result Summary
MembersHuman studies
18 of these 91 human studies gave the ingredient by drip or inhaler, not by mouth.
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Review Totals and Summary
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RAL Summary
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Supplement Facts
Selenium 25 mcg · N-Acetyl Cysteine 600 mg
| Selenium (elemental) (from L-Selenomethionine) | 25 mcg | 45% |
| N-Acetyl Cysteine (NAC) | 600 mg | † |
Other ingredients: Hypromellose (cellulose capsule), Stearic Acid (vegetable source), Citric Acid and Microcrystalline Cellulose.
Directions: Take 1 capsule twice daily.
Label source: the brand's label · Report a label change
Where to Buy
Swanson · Pasioonline · Freshthyme
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Graded October 28, 2026 by the Reverse Age Lab evidence engine, from human studies, real reviews and our biohacker panel. How we grade. Is this medical advice? No. Rala organizes the published evidence; go over any change with your doctor, especially if you take meds.

