Biotin foods

This page shows the biotin in foods; functions, deficiency risk and the evidence on supplements are in the biotin guide. This guide does not recommend personal doses.

Which foods contain biotin?

NIH reports that many foods contain some biotin; those containing the most are organ meats, eggs, fish, meat, seeds, nuts and some vegetables (such as sweet potato). Biotin content can vary even within the same food: for example, plant variety and season in grains, and processing methods such as canning, can affect the amount of biotin. ^[1]

Biotin food table: micrograms per serving

The values below are taken from the NIH table. Servings are US measures (1 ounce is about 28 g, 3 ounces about 85 g; 1 cup is about 240 mL); “percent DV” is relative to 30 µg, the Daily Value for adults in the US, and is not the same measure as EFSA’s adequate intake value of 40 µg. In the NIH table, egg yolk does not appear as a separate row; for egg, a “whole, cooked” row is given and the serving amount is not stated. ^{[1] [3]}

What can be read from the table: a single serving of cooked liver reaches NIH’s adequate intake value of 30 µg; one cooked egg is about a third of that; nuts, seeds and sweet potato give a smaller but meaningful contribution; dairy products, bread and fruits contain very little. NIH also notes that in the US the FDA counts foods providing 20% or more of the Daily Value as a “high source”; in the table only liver and egg exceed this threshold. The content of products sold in Türkiye may differ from those in the table. ^[1]

How reliable are biotin values?

The NIH table is based on measurements that Staggs and colleagues made in 2004 on 87 foods using an HPLC/avidin binding method. The same study reports that the measurements markedly disagreed with biotin values published at the time for many foods: values came out as much as 247 times higher or up to 36% lower than the published value; of the 51 foods that could be compared, only seven agreed within analytical variability, and the authors stated that published food biotin values are highly likely to be wrong. For this reason, the numbers in the table should be read as indications of approximate magnitude, not as exact figures. NIH also reports that USDA FoodData Central does not list the biotin content of foods. ^{[2] [1]}

How is biotin in food absorbed?

Most of the biotin in foods is bound to protein; the free biotin share is smaller. According to NIH, proteases and peptidases in the digestive tract break protein-bound biotin into biocytin and biotin-oligopeptides, and the biotinidase enzyme in the intestinal lumen releases free biotin from these; free biotin is absorbed from the small intestine and most of it is stored in the liver. In biotinidase deficiency, this step does not work, so deficiency develops even if intake is normal. Absorption of free biotin in supplements is, according to NIH, 100% even at doses of up to 20 mg per day; no such percentage is given for foods, and the values in the table show the total amount in the food, not the amount absorbed. ^[1]

Does raw egg white block biotin absorption?

Avidin, a glycoprotein found in raw egg white, binds biotin tightly and blocks biotin absorption from the gut. According to NIH, cooking denatures avidin and makes it unable to impair biotin absorption. For this reason, the 10.0 µg value in the table is for cooked egg; raw egg white cannot be counted as an adequate biotin source. NIH also states that severe biotin deficiency has never been reported in a healthy person on a normal mixed diet; that is, raw egg white reducing absorption does not mean deficiency is expected on its own. ^[1]

Is enough biotin obtained from food?

NIH reports that there are no nationally representative intake data for the US, but that in other Western populations mean intake from food is about 35–70 µg per day and most people get adequate biotin. The adequate intake values are 30 µg for adults at NIH (FNB) and 40 µg at EFSA; EFSA based this value on intakes observed in the EU. ^{[1] [3]}

According to NIH, biotin deficiency is rare. For groups at risk (such as biotinidase deficiency, chronic alcohol use, and some long-term antiepileptics) the situation is different and is outside the scope of this guide; details are in the biotin guide.

Does the biotin in foods distort tests?

The reported cases of test interference involve high-dose supplements. In the cases reported by NIH, false thyroid results were seen in patients taking 10–300 mg of biotin per day, and even a single 10 mg dose disrupted thyroid tests done within 24 hours. 10 mg means 10,000 µg; this is about 140–290 times the mean of 35–70 µg obtained from food in Western populations (calculated). NIH states that high intakes, and possibly even intakes above the adequate intake value, can carry such a risk; however, the interference cases reported relate to supplement doses. ^[1]