Your NAD+ Builder
Niacin is the building block for NAD+ and NADP+—coenzymes involved in over 400 metabolic reactions. NAD+ is having a moment in longevity research because it declines with age and is essential for DNA repair, cellular energy, and sirtuin activation. Niacin is also the oldest lipid-lowering drug, known for raising HDL.
What is Vitamin B3 (Niacin)?
Vitamin B3 (niacin/nicotinamide) is the precursor to NAD+ and NADP+. It comes in several forms: nicotinic acid (causes flush, lowers lipids), nicotinamide (no flush), and nicotinamide riboside/NMN (newer longevity supplements). Your body can also make small amounts from tryptophan.
↑ What High Vitamin B3 (Niacin) Means
High-dose niacin supplementation causes the "niacin flush"—intense facial redness and tingling. Very high doses can cause liver damage. Prescription niacin was used for lipid management but is less common now.
Common symptoms:
Niacin flush (redness, tingling, warmth) · Nausea · Liver damage at very high doses · Elevated blood glucose
↓ What Low Vitamin B3 (Niacin) Means
Severe niacin deficiency causes pellagra: the "4 D's"—dermatitis, diarrhea, dementia, and death. Subclinical deficiency impairs energy production and DNA repair. Rare in developed countries due to food fortification.
Common symptoms:
Fatigue · Headache · Depression · Memory loss · Pellagra: photosensitive dermatitis, diarrhea, dementia
Why It Matters
When normal:
Precursor to NAD+ (essential for 400+ reactions)
DNA repair and cellular energy
Raises HDL 15-35% (nicotinic acid form)
Lowers triglycerides
May support healthy aging (NAD+ research)
Risks if abnormal:
Deficiency: pellagra (dermatitis, diarrhea, dementia)
High-dose nicotinic acid: flushing, liver damage, glucose elevation
NAD+ declines with age—may contribute to aging processes
What Can Cause Abnormal Levels?
Dietary Deficiency
35% likelyRare in developed countries. Risk in diets based primarily on corn (which has bound, unabsorbable niacin).
Alcohol Use Disorder
35% likelyAlcohol impairs niacin absorption and increases demand.
Carcinoid Syndrome
Tumors divert tryptophan away from niacin synthesis, causing deficiency.
Isoniazid Therapy
TB medication interferes with niacin metabolism.
What You Can Do
Niacin foods: poultry, tuna, salmon, peanuts, mushrooms, fortified grains
Impact: Prevents deficiency \u00B7 Timeline: 2-4 weeks
If lifestyle changes aren't enough:
Nicotinamide: 500mg daily (no-flush form)
Impact: Supports NAD+ production without flushing \u00B7 Timeline: 4-8 weeks
NMN or nicotinamide riboside: 250-500mg daily for NAD+ support
Impact: Emerging longevity research shows NAD+ restoration \u00B7 Timeline: 4-8 weeks
Recommended retest: 3-6 months
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