Niacin

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Connected to · 5

food source · 1

Chicken
Chicken is a good dietary source of niacin (vitamin B3). Niacin is the raw material for NAD, the molecule that carries hydrogen when cells draw energy out of food.
Mechanism · 2
Mechanism · The go-between that carries hydrogen
Getting energy from food means pulling hydrogen off the fuel and finally handing it to oxygen. A molecule has to catch the hydrogen, carry it over and hand it off, and its backbone is made from niacin: empty-handed it is called NAD, and carrying hydrogen it is called NADH. So niacin does not give you energy directly; it is the tool that lets energy be drawn out. In severe deficiency, the skin, the digestive tract and the nerves run into trouble together, because cells in all three turn over quickly and burn a lot of energy.
In practice · What else comes with the meat
Niacin comes in the same piece of chicken as complete protein, vitamin B6 and selenium. Dark meat such as thigh has more iron and zinc than breast; if you want the most protein with the least fat, breast is still the choice.

synergy · 1

Riboflavin
The electron transport chain that makes energy in mitochondria has two main entry points: one takes electrons from NADH and the other from FADH₂. NAD comes from niacin (B3) and FAD from riboflavin (B2), so the two vitamins each guard one entry to the same chain.

cofactor · 1

α-Lipoic Acid
On the two large enzyme complexes that feed fuels such as pyruvate into the citric acid cycle, lipoic acid acts like a swinging arm, passing the electrons stripped off the fuel through a riboflavin-based coenzyme to NAD⁺. NAD⁺ is made from niacin (vitamin B3) and is the last to take the baton in this relay.

contrast · 2

NMN / NR
NMN, NR, niacin and nicotinamide all belong to the vitamin B3 family and all feed NAD⁺ synthesis in the cell. NMN and NR are sold as new anti-aging products; niacin and nicotinamide are cheap old vitamins. In human trials NMN and NR did raise NAD⁺ in the blood (Martens 2018, Yoshino 2021), but whether that brings any health benefit has not been shown.
Chromium
In the 1970s and 1980s, a popular glucose tolerance factor theory held that chromium and niacin formed a complex that helped insulin work, and marketing used it widely. Later research did not confirm this complex, and whether chromium is an essential nutrient at all has been questioned. It is a historical claim, not a reason to take supplements.

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Two electron-carrying molecules

EVIDENCEGUIDE 1 · MECH 1

READ THE ORIGINAL

Inside the cell, vitamin B3 is built into two molecules, and NADP. Their job is to catch electrons and hand them on. That is how cells pull energy out of food, and how they build things and fend off oxidation.

B3 in food and supplements comes in several forms: niacin, nicotinamide, and precursors such as nicotinamide riboside () and nicotinamide mononucleotide (). Once inside the cell, all of them feed the same NAD⁺ pool.

An analogy: NAD is like a power line that carries electrons from food to the generating station; NADP is like the point of use, spending electrons to build and to put out fires. The two cannot stand in for each other. The analogy ends there; they are not actual wires.

NAD (NAD⁺ when empty-handed, NADH once it holds electrons) leans toward breaking fuel down for energy. In the main energy loop, the tricarboxylic acid () cycle, it collects electrons and carries them into the mitochondria's power chain, which makes , the energy currency.NADP leans toward building and defense. Making fat, making cholesterol, and recycling glutathione for antioxidant defense all rely on (the loaded form of NADP, carrying electrons) to hand over electrons.
Cells keep NAD mostly empty-handed and NADP mostly loaded, so one system collects electrons while the other delivers them, without getting in each other's way.

Watch this step as a mechanism animationOpen mechanism

Educational content, not medical advice — consult a clinician.

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