Flashcards in Niacin (B3) Deck (13)
60 mg tryptophan = 1 mg niacin
Niacin equivalent (NE)
Creates NAD+ in liver
NMN (n methyl nicotinamide)
Liver catalyzes the hydrolysis of nicotinamide with glycohydrolase.
3 D's: dermatitis, diarrhea, dementia, (death)
Can be caused by deficiency in B6, riboflavin, and iron.
Caused by poor tryptophan diet.
Bound niacin not available (corn). Lime treatment.
Malabsorption, alcoholism, cancer drugs, TB.
16 NE men
14 NE women
1 NE = 1 mg niacin/ 60 mg tryptophan
Urinary excretion of niacin metabolite NMN
>1 mg/d desirable
Plasma not good indicator b/c concentrations of niacin are low in healthy individuals who are assessed.
Electron transport (NAD)
Biosynthesis pathways (NADPH)
NAD: glycolysis, oxidative decarboxylation pyruvate, oxidation of acetyl CoA, beta oxidation
NADPH: fatty acid synthesis, regenerates glutathione and vitamin C, folic acid metabolism
Niacin and Vitamin C
Glutathione recycles vitamin C
Vitamin c regenerates/ reduces vitamin E
UL 35 mg
Vasodilation due to increased histamine
6 g nicotinic acid NOT nicotinamide to treat hypercholsterolemia
Meats especially chicken and tuna.
100% absorption up to 3-4 g dose