NAD+ decline with aging is driven by two mechanisms: reduced synthesis and increased consumption (primarily by CD38 in senescent immune cells). Senolytics eliminate the highest CD38-expressing cells, reducing the NAD+ drain. NMN/NR replenishes the pool. Quercetin inhibits CD38 directly. This three-pronged approach addresses all major NAD+ decline mechanisms simultaneously.

Which should I prioritize if budget allows only one: NMN or fisetin?

If you are over 50 with established senescent cell burden: fisetin (monthly protocol) addresses the root cause. If you are under 40 with low senescent burden: NMN addresses the NAD+ decline driving early aging. Combine as budget allows.

How do I know if my NAD+ is improving from senolytics?

Blood NAD+ (whole blood) can be measured via specialized testing (Jinfiniti, Alive by Science). Before-and-after testing (post-senolytic cycle at 4 weeks) can confirm the expected NAD+ increase from senescent cell clearance.