NR 300 mg is both a studied amount and a familiar capsule label. Tru Niagen’s 300 mg product supplies nicotinamide riboside chloride, which should be distinguished from direct NAD+ and from other forms of vitamin B3.
A matching ingredient and amount can make research relevant, but it does not answer every health question. The main evidence discussed here concerns blood NAD, not a promise that each user will notice more energy or age more slowly.
300 mg NR has blood-NAD evidence and a clear one-capsule product example. That does not establish a universal daily need or guarantee a noticeable health benefit.
What the 300 mg product actually contains
Tru Niagen’s current Supplement Facts panel lists 300 mg Niagen, identified as nicotinamide riboside chloride, per one-capsule serving. Other products in the brand’s range have different serving sizes and formulas, so the product name alone is insufficient.
Use our Tru Niagen review for the brand context. Check the selected bottle and full panel rather than assuming that every product bearing the same logo contains 300 mg per capsule.
What the dose-ranging trial found
The 300 mg arm of the 2019 randomized trial showed increased whole-blood NAD relative to baseline and placebo, beginning within seven days and sustained during the eight-week study. That result supports a blood-biomarker claim under the study conditions.
It does not establish that the measured increase caused an improvement in everyday function. Keep the laboratory outcome separate from broader claims on a product page.
Why 300 mg is not a daily requirement
A studied supplement amount is not automatically a nutritional requirement. NIH’s niacin guidance explains nutritional vitamin B3 in its own framework; a branded NR serving should not be presented as the amount of NAD-related supplementation every adult needs.
A label’s missing Daily Value is not an invitation to treat more as better. It is a reason to avoid confusing the product’s serving with an established personal target.
Compare plain NR with an NR combination
Elysium Basis combines NR with pterostilbene, creating a different formula and evidence question. The Tru Niagen versus Elysium comparison examines the additional ingredient and study context.
Sorting the products only by NR milligrams would omit the extra ingredient and its implications for interpreting results. A combination’s claimed advantage needs evidence for the combination, not just a familiar precursor name.
Practical checks before choosing a bottle
Confirm capsule count, full-serving amount, purchase price, subscription terms, and any added active ingredients. If comparing the 300 mg product with NR 1,000 mg, do not assume a proportionate increase in benefit.
Bring the actual panel to a clinician or pharmacist when considering interactions or suitability. A study amount is useful information for that conversation, not a replacement for it.
Sources & reading notes
Editorial source review updated September 19, 2026. Provider pages describe their own offers; inclusion does not verify a product or its results.
- Conze et al. (2019): NR dose-ranging trial Eight-week trial of 100, 300, and 1,000 mg NR. The 100 mg blood-NAD result differed from baseline but not placebo; biomarker findings are not longevity outcomes.
- Tru Niagen: 300 mg capsules Manufacturer label lists NR chloride; not direct NAD+.
- NIH Office of Dietary Supplements: niacin Nutritional and biochemical context; not a clinical trial of NAD+ injections.
- Elysium: Basis Manufacturer label for NR plus pterostilbene; claims and lot documentation are separate evidence.
- FDA: questions and answers on dietary supplements Regulatory categories and limits of premarket review.
Educational information, not individualized medical advice. We do not claim medical review or firsthand treatment experience. Read our review standards and commercial disclosure.