What Niacin Does
Niacin (vitamin B3) is a water-soluble vitamin that becomes the coenzymes NAD and NADP in the body. In that form it drives several hundred enzyme reactions — most of them in the pathways that turn carbohydrate, fat, and protein into usable energy. It also supports skin, digestive tract, and nervous system health.
The FDA Daily Value is 16mg. Severe deficiency causes pellagra, historically common where corn was the dietary staple, but it is rare in the US today — niacin is widespread in animal protein, and enrichment of flour and cereals has been standard practice since the 1940s.
Whole-Food Sources, per 100g
Fish and poultry lead the whole-food list. All values are per 100g of edible portion, cooked where a food is normally eaten cooked.
| Food (FDC ID) | Niacin (mg) | % Daily Value (16mg) | Calories (kcal) |
|---|---|---|---|
| Rice bran, crude(169713) | 34.0 | 213% | 316 |
| Tuna, yellowfin, cooked, dry heat(172006) | 22.1 | 138% | 130 |
| Anchovy, European, canned in oil, drained(174183) | 19.9 | 124% | 210 |
| Tuna, skipjack, cooked, dry heat(172005) | 18.8 | 118% | 132 |
| Chicken breast, meat only, fried(171078) | 14.8 | 93% | 187 |
| Peanuts, all types, dry-roasted, no salt(173806) | 14.4 | 90% | 587 |
| Mushrooms, shiitake, dried(168436) | 14.1 | 88% | 296 |
| Chicken breast, meat only, roasted(171477) | 13.7 | 86% | 165 |
| Tuna, light, canned in water, drained(171986) | 13.3 | 83% | 116 |
| Turkey, light meat, cooked, roasted(171491) | 11.8 | 74% | 147 |
| Pork tenderloin, lean only, roasted(168250) | 7.4 | 46% | 143 |
| Beef, ground, 93% lean, cooked(174754) | 5.4 | 34% | 192 |
| Bread, whole-wheat, commercially prepared(172688) | 4.4 | 28% | 252 |
| Almonds(170567) | 3.6 | 23% | 579 |
Source: USDA FoodData Central. % Daily Value calculated against the FDA reference of 16mg.
⚡ See the full niacin ranking across all foods →Why the Raw Ranking Looks Strange
If you sort the entire USDA database by niacin, almost nothing above ranks near the top. The list is instead led by yeast extract spread (127.5mg per 100g), fortified wheat bran flakes (90.6mg), fortified drink powders (80.0mg), and energy bars (around 45mg).
None of these are naturally high in niacin — they are fortified. US enrichment standards add niacin back to refined flour, breakfast cereals, and many formulated products, often at multiples of the Daily Value per 100g of dry product. That is a real dietary contribution, but it says nothing about the food itself, and per-100g figures for dry cereal or drink powder overstate what anyone actually eats in one sitting.
The table above deliberately excludes fortified and formulated products so the comparison reflects niacin that is intrinsic to the food.
Your Body Makes Niacin from Protein
Niacin is unusual among vitamins: the body synthesizes it from tryptophan, an essential amino acid, at a ratio of roughly 60mg tryptophan to 1mg niacin. This is why niacin requirements are often expressed in niacin equivalents (NE), which count both preformed niacin and the contribution from dietary protein.
The practical consequence is large. Foods that look poor on a niacin table can still contribute meaningfully once tryptophan is counted:
| Food (FDC ID) | Niacin (mg) | % Daily Value (16mg) | Calories (kcal) |
|---|---|---|---|
| Egg, whole, hard-boiled(173424) | 0.1 | 1% | 155 |
| Milk, whole, 3.25% milkfat(171265) | 0.1 | 1% | 61 |
| Rice, white, long-grain, cooked(168935) | 0.4 | 3% | 130 |
| Beans, black, cooked, boiled(173735) | 0.5 | 3% | 132 |
| Lentils, cooked, boiled(172421) | 1.1 | 7% | 116 |
Eggs and milk contain almost no preformed niacin, yet both are rich in tryptophan — so a protein-adequate diet supplies far more niacin equivalent than a preformed-niacin table suggests. If you are eating enough protein, you are almost certainly meeting your niacin needs.
Cooking and Retention
- ✓Niacin is water-soluble, so it leaches into cooking water. Soups, stews, and pan sauces keep what boiling would discard.
- ✓It is comparatively heat-stable — losses from cooking alone are smaller than for vitamin C or folate.
- ✓Canned tuna keeps most of its niacin (13.3mg per 100g drained), making it one of the most convenient sources available.
- ✓Dried shiitake concentrate to 14.1mg per 100g, but a serving is only a few grams rehydrated.
- ✓Niacin from supplements (as nicotinic acid) can cause skin flushing at high doses, which is why a tolerable upper intake level exists. Food sources do not cause this.
Key Takeaways
- ✓Among whole foods, yellowfin tuna leads at 22.1mg per 100g cooked — 138% of the 16mg Daily Value in one portion.
- ✓Anchovies (19.9mg), chicken breast (13.7mg roasted), dry-roasted peanuts (14.4mg) and dried shiitake (14.1mg) are the other standouts.
- ✓The unfiltered USDA ranking is topped by fortified cereals, drink powders, and energy bars — that is enrichment, not the food.
- ✓The body converts tryptophan to niacin at about 60:1, so eggs and milk contribute despite showing ~0.1mg of preformed niacin.
- ✓Deficiency is rare in the US. If protein intake is adequate, niacin generally takes care of itself.
- ✓Water-soluble but heat-stable: cook in liquid you will eat, and losses stay small.
Related reading: Vitamin B1, Vitamin B2, Vitamin B6, Vitamin B12, and Protein Per 100g Compared.
Data Source
・USDA FoodData Central — Foundation Foods and SR Legacy
・FDA Daily Values (21 CFR 101.9)
This article is general nutrition information and is not intended to diagnose or treat any condition.