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Tools›Compare›NAD+ vs P21

NAD+ vs P21

Side-by-side comparison of key properties, dosing, and research.

Anti-Aging & Longevity
NAD+
Cognitive EnhancementAnti-Aging & Longevity
P21
Summary
NAD+ (Nicotinamide Adenine Dinucleotide) is a coenzyme found in all living cells that declines dramatically with age. It is critical for energy metabolism, DNA repair, and sirtuin activation. IV and subcutaneous NAD+ supplementation is used in anti-aging protocols and addiction recovery programs.
P21 is a synthetic peptide derived from CNTF (ciliary neurotrophic factor) that promotes hippocampal neurogenesis, enhances memory and spatial learning, and may reduce amyloid-beta pathology. It is used as a neurogenic and cognitive enhancer with potential anti-Alzheimer's applications.
Half-Life
Varies by route; IV provides direct cellular delivery
Not well characterized; likely short, but neurogenic effects persist long after administration
Admin Route
IV, SubQ, Oral
SubQ, Intranasal
Research
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Typical Dose
500–1000 mg
100–500 mcg
Frequency
Daily for 4–10 days (loading), then monthly maintenance
Once daily
Key Benefits
  • Restored cellular energy production (ATP)
  • Sirtuin activation for longevity and metabolic regulation
  • Enhanced DNA repair capacity
  • Improved mitochondrial function and biogenesis
  • Cognitive clarity and mental energy
  • Reduced inflammation
  • Addiction withdrawal support (opioids, alcohol, benzodiazepines)
  • Improved sleep quality
  • Enhanced athletic endurance
  • Promotes hippocampal neurogenesis
  • Enhances spatial memory and learning
  • Increases BDNF expression
  • Reduces amyloid-beta plaque formation (animal models)
  • Anti-tau pathology potential
  • Cognitive enhancement without stimulant effects
  • Potential therapeutic for Alzheimer's and cognitive aging
Side Effects
  • Flushing and warmth during IV infusion
  • Nausea during rapid IV administration
  • Chest tightness (from rapid infusion — slow the rate)
  • Injection site irritation (subcutaneous)
  • +1 more
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
Stacks With
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