What is Nicotinamide Riboside?
Nicotinamide Riboside (NR) is a form of vitamin B3 that serves as a direct precursor to NAD+ (Nicotinamide Adenine Dinucleotide). Found in trace amounts in milk, yeast, and green vegetables, NR has emerged as one of the most well-researched NAD+ boosters available.
NAD+ is essential for over 500 enzymatic reactions in the body, including energy metabolism, DNA repair, and cellular signaling. As we age, NAD+ levels decline by approximately 50% every 20 years, contributing to age-related decline and disease.
NR supplementation offers a proven way to restore NAD+ levels. Unlike nicotinamide or niacin, NR is highly efficient at raising NAD+ without causing flushing or other side effects commonly associated with B3 vitamins.
How NR Boosts NAD+
NR is converted to NAD+ through a two-step process involving the enzyme nicotinamide riboside kinase (NRK). This pathway is highly efficient and bypasses rate-limiting steps in other NAD+ biosynthetic routes.
Once absorbed, NR enters cells where it is phosphorylated to NMN, then converted to NAD+. Studies show oral NR supplementation can increase blood NAD+ levels by 40-90% within weeks of consistent use.
NR's Key Functions
- Activates SIRT1-7 sirtuins for cellular repair and longevity
- Enhances mitochondrial biogenesis and energy production
- Supports PARP enzymes for DNA damage repair
- Regulates circadian rhythm and metabolic health
Clinical Research
NR has more published human clinical trials than any other NAD+ precursor. A landmark 2016 study in Nature Communications confirmed that oral NR safely and effectively increases NAD+ levels in humans.
Research published in Cell Metabolism (2018) demonstrated that NR supplementation improved insulin sensitivity in prediabetic individuals. Another trial showed improvements in vascular function and reduced arterial stiffness in older adults.
The NIAGEN brand of NR has received FDA GRAS (Generally Recognized as Safe) status, further validating its safety profile for human consumption.
Benefits for Longevity
NR offers multiple pathways to support healthy aging and longevity:
- Cellular Energy: Restores mitochondrial function for improved energy and reduced fatigue
- Brain Health: Supports neuronal metabolism and may protect against cognitive decline
- Cardiovascular Health: Improves blood vessel function and reduces inflammation
- Metabolic Health: Enhances insulin sensitivity and supports healthy glucose metabolism
- DNA Repair: Activates PARP enzymes essential for maintaining genomic integrity
Dosage Recommendations
Clinical studies have used doses ranging from 100mg to 1000mg daily, with most showing benefits at 300-600mg per day. The patented NIAGEN form is the most extensively studied.
Dosage Guidelines
- Beginners: 250-300mg daily for 4-6 weeks
- Maintenance: 300-500mg daily
- Therapeutic: 500-1000mg daily (split doses)
- Best time: Morning with or without food
NR vs NMN: Which to Choose?
Both NR and NMN are effective NAD+ precursors with distinct advantages. NR has more published human clinical trials and FDA GRAS status. NMN may have advantages in direct cellular uptake through the Slc12a8 transporter.
NR is more stable and has been on the market longer with established safety data. NMN is one step closer to NAD+ in the metabolic pathway. Many longevity enthusiasts use both or alternate between them.
The choice often comes down to personal preference, cost, and individual response. Both effectively raise NAD+ levels when taken at appropriate doses.
