NMN
Nicotinamide Mononucleotide · NAD+ Precursor
Supplement
NAD+LongevitySublingualSinclair Protocol
Direct NAD+ precursor that enters cells via the Slc12a8 intestinal transporter. Requires only one conversion step to become NAD+. Available in sublingual form for potentially faster absorption. Standard dose 250--500mg/day. More expensive than NR but favored in Sinclair-style protocols.
NMN dosing guide →
NR
Nicotinamide Riboside · NAD+ Precursor
Supplement
NAD+LongevityMore RCTsLower Cost
NAD+ precursor absorbed as NR intact and converted to NMN intracellularly before becoming NAD+. Has more published human randomized controlled trials than NMN. Standard dose 300mg/day. Lower cost per gram than NMN. Does not have a sublingual form. Well-tolerated with a strong safety record.
NR dosing guide →
The Verdict
Both NMN and NR reliably raise NAD+ levels in humans -- that is settled. The debate is which does it more efficiently. NMN has a direct intestinal transporter and one fewer conversion step to NAD+, which is theoretically more efficient. NR has more published human randomized controlled trials. For most people, start with NR (cheaper, more evidence) and consider switching to NMN if you want the sublingual option or want to follow Sinclair's specific protocol. At standard doses the real-world difference is likely small. Consistency matters more than which one you choose.
Frequently Asked Questions
Is NMN or NR better for raising NAD+?
Both NMN and NR reliably raise blood NAD+ levels in humans -- that is proven in multiple RCTs. NMN has a direct intestinal transporter (Slc12a8) and requires only one conversion step to NAD+, which is theoretically more efficient. NR has more published human randomized controlled trials. For most people the real-world NAD+ increase is similar at standard doses. Start with NR if cost is a factor; switch to NMN if you want the sublingual option or follow Sinclair-style protocols.
What dose of NMN should I take?
Standard NMN dose is 250--500mg/day taken in the morning, preferably fasted. Research doses range from 250mg to 1g/day. David Sinclair has reported taking 1g/day. Most human studies showing NAD+ elevation used 250--500mg. Higher doses increase NAD+ further but also increase cost. Start at 250mg and assess after 4--8 weeks.
Can I take NMN and NR together?
Yes, there is no known safety concern with combining NMN and NR. However, there is little evidence that combining them produces additive benefits beyond what either alone achieves at a sufficient dose. Most researchers and practitioners use one or the other rather than both. If budget allows, stacking is unlikely to be harmful but may not be necessary.
Does NMN need to be refrigerated?
Yes, refrigeration is recommended for both NMN and NR to preserve potency. NMN is sensitive to heat and moisture, and room-temperature storage over months can degrade the compound. Keep in a sealed container in the refrigerator. Some manufacturers package NMN with desiccants and dark glass to extend shelf life at room temperature, but cold storage is the safer default.
How long does NMN or NR take to work?
Blood NAD+ levels can increase within hours of a single dose. However, meaningful physiological effects -- such as improved energy, better sleep, or enhanced recovery -- typically take 4--12 weeks of consistent use. Some people notice subjective energy improvements in the first 1--2 weeks. NAD+ declines with age, so younger people may notice less change than those over 40.