People mainly take Niacinamide for skin & hair, sleep, longevity. Based on 20 first-hand reports and 144 meta-analyses & systematic reviews in the medical literature. Ranked #892 of 1,974 overall.
Of reports that state an outcome, 25% are positive.
Of the people who reported each effect, the share who said it got better.
Systematic reviews and meta-analyses from PubMed, with their published conclusions.
3+ meta-analyses or systematic reviews and 10+ randomized controlled trials in humans. The grade measures how much human research exists — read the conclusions below for what it found.
Conclusion: Oral nicotinamide should be considered in healthy patients or organ transplant recipients with history of skin cancer (GRADE: weak recommendation; moderate-quality evidence), in particular of BCC and cSCC.
PubMed 35134311 ↗Conclusion: Retinoids, hydroxy acids and broad-spectrum sunscreen were supported by the greatest number of high-quality studies. Ongoing inflammation may be subtle, especially in darker skin phenotypes. Herein, we proposed an evidence-based algorithm for PIH based on the high-quality studies. There is a need to adopt a validated outcome measure for PIH to better compare efficacy between various treatments in future studies.
PubMed 34525885 ↗Conclusion: The most frequently used laser in treating AH was QS Nd-YAG without having any severe adverse effect. Various topical treatments including Niacinamide, desonide, HQ, AHA, and a few herbal extracts were shown to be effective for AH.
PubMed 40843925 ↗Conclusion: Overall, NAD⁺ augmentation shows clear biological activity, but clinical effectiveness for anti-aging or wellness outcomes remains inconclusive. Larger, well-designed randomized trials with longer follow-up and prespecified clinically meaningful endpoints are needed, particularly for parenteral approaches.
PubMed 41655607 ↗As stated by users — not a recommendation. Follow the label or your doctor.
How often each side effect came up across all reports.
Verbatim quotes, shortened only — each links to the original discussion.
“Niacinamide isn't a good option bc it inhibits sirtuin 1.”
“Niacinamide had been shown to increase the amount of NAD+ in skin, that's also one with evidence on wrinkles and dark spots.”
“using Ordinary Niacinamide and Alpha Arbutin and hyalauronic acid serums tropically”
“Exercise (by far the best thing), l-theanine, niacinamide, and phenibut on very rare occasions”
“I also take...niacinamide 50 mg morning and night”
User data from public discussions; research from PubMed. Information only, not medical advice — talk to a doctor before starting, stopping or combining anything. Data updated October 2, 2026. How we rate