Oral administration of 1.25g of NMN per day was proven safe
The safety of 1.25g NMN orally per day was demonstrated in Japanese human studies
NAD+ (nicotinamide adenine dinucleotide) is a key coenzyme in energy metabolism in the human body, and its levels gradually decline with age, which can lead to metabolic disorders and a range of age-related diseases.
NMN (nicotinamide mononucleotide) is a direct precursor of NAD+, so it is hoped that the level of NAD+ can be increased by supplementing with NMN.
Previous clinical trials have shown that oral doses of 250mg/ day of Nicotinamide Mononucleotide do not cause adverse effects, but the Mitsubishi researchers found that more than four times this dose is still safe.
The study published in Scientific Reports, a Nature journal, in August 2022.
The subjects in this study healthy men and women in their mid-30s who assigned to the Nicotinamide Mononucleotide group (16 people) and the placebo group (15 people) in a double-blind condition.
The NMN group required to take 200mL of liquid medicine every day, in which 1250mg of Nicotinamide Mononucleotide dissolved, as well as dextrin, maltitol and flavor substances. The placebo group took the same amount of placebo medicine with only the adjuvant.
The duration of the study was four weeks, and two weeks after the end of the study, at week 6, the subjects underwent an additional blood test to assess the subsequent effects of stopping taking NMN.
The results found that 1250mg/ day of oral NMN did not cause adverse reactions in the subjects, and the basic indicators in their blood were not abnormal, and there was no significant change before the start of the experiment.
Unfortunately, the study did not measure the levels of metabolites associated with NMN in the subjects,
especially NAD+, so the effect of NMN supplementation cannot be verified.
However, considering that large doses of NAM (niacinamide) and NA (niacin) have the risk of liver toxicity to humans, 2,3,
and neither of them can synthesize NAD+ through a single step reaction like NMN,
the results of this clinical trial show that NMN a safer choice when large doses of supplements needed.
References:
- 1. Fukamizu, Y., Uchida, Y., Shigekawa, A. et al. Safety evaluation of β-nicotinamide mononucleotide oral administration in healthy adult men and women. Sci Rep 12, 14442 (2022).
- 2. Ito, T. K. et al. A single oral supplementation of nicotinamide within the daily tolerable upper level increases blood NAD+ levels in healthy subjects. Transl. Med. Aging 5, 43–51.
- 3. Knip, M. et al. Safety of high-dose nicotinamide: A review. Diabetologia 43, 1337–1345.
