NMN moved no measure of blood sugar, blood fats or weight
Two meta-analyses looked at fasting glucose, insulin, HbA1c, the lipid panel, weight and BMI at 250 up to 2,000 mg a day. Not one moved against placebo.
What the study found
Pooled trials find NMN changing no metabolic marker at all
Two meta-analyses of the randomised NMN literature looked at fasting glucose, fasting insulin, HbA1c, insulin resistance, the lipid panel, body weight and BMI. Not one moved against placebo, at doses from 250 up to 2,000 mg a day and durations up to 24 weeks.
The caveat · Tested mostly in healthy people
Eight trials and 342 people in the metabolic pool, so a modest real effect could be missed. Participants were mostly healthy and not diabetic, which is the population least likely to show a metabolic improvement and leaves the question open in people who already have metabolic disease. Several pooled trials ran fourteen days, far too short for HbA1c, which reflects about three months of blood sugar, to move at all.