A double-blind, placebo-controlled trial has demonstrated that supplementation with nicotinamide mononucleotide (NMN), a precursor to the essential coenzyme NAD+, significantly improves cognitive function and brain blood flow in adults over 60.
The 12-month trial enrolled 280 cognitively healthy participants aged 60 to 85 and randomized them to receive either 500mg of NMN daily or a placebo. Those receiving NMN showed a 15% improvement in working memory, a 12% improvement in processing speed, and a 20% increase in cerebral blood flow as measured by functional MRI.
"NAD+ levels decline dramatically with age, and the brain is particularly vulnerable to this decline," said Dr. Shin-ichiro Imai of Washington University in St. Louis, a pioneer in NAD+ research. "This trial provides the most robust evidence to date that replenishing NAD+ through NMN supplementation can meaningfully protect cognitive function."
NAD+ is essential for mitochondrial energy production, DNA repair, and the activity of sirtuins — proteins that regulate aging and stress response. The age-related decline in NAD+ is considered one of the fundamental drivers of aging across multiple organ systems.
While the results are encouraging, researchers caution that long-term safety data is still being collected. The study also found that benefits were most pronounced in participants with the lowest baseline NAD+ levels, suggesting that testing NAD+ status before supplementation may help identify those most likely to benefit.