Safety evaluation of β-nicotinamide mononucleotide oral administration in healthy adult men and women

This randomized double-blind trial tested a relatively high oral NMN dose, 1,250 mg once daily, in 31 healthy adults for four weeks. The study was designed primarily to assess short-term safety rather than clinical benefit.

The investigators reported no severe adverse events and no clinically concerning changes in anthropometric measures, hematology, clinical chemistry, urinalysis, or body composition. The findings therefore add short-duration tolerability evidence for the specific tested formulation and dose.

Because the trial was small and lasted only four weeks, it cannot establish long-term safety, uncommon adverse-event rates, anti-aging effects, or health benefits.

• No severe adverse events were observed during the four-week intervention.
• Clinical laboratory, urine, body-composition, and physical measurements did not show changes judged to exceed normal physiological variation.
• The study directly tested repeated 1,250 mg/day oral NMN, a higher daily dose than most earlier human NMN trials.
• The publication's conclusions concern short-term safety and tolerability, not demonstrated clinical efficacy.

• Only 31 participants were studied.
• Exposure lasted four weeks, so longer-term safety was not evaluated.
• The sample consisted of healthy adults and may not generalize to people with major chronic diseases.
• The study was funded by the manufacturer of the NMN test material, and five authors were company employees.
• The study was not powered to detect rare adverse events or to establish anti-aging or disease-related benefits.