Riboflavin (vitamin B2) is a water-soluble B vitamin that forms two coenzymes, FMN and FAD, which help produce energy and support cell growth, development and function1.
As part of FMN and FAD, riboflavin helps turn the food you eat into energy2.
Needed for the growth, development and function of the cells in your body2.
Its coenzymes take part in breaking down fats, drugs and steroids1.
FAD is needed to make niacin from tryptophan, and FMN to turn vitamin B6 into its active form1.
More than 90% of the riboflavin in food is in the form of FAD or FMN, and most of it is absorbed in the upper small intestine1. The body stores only small amounts, in the liver, heart and kidneys; excess is either not absorbed or leaves in urine1.
| Food and serving | Amount |
|---|---|
| Breakfast cereal, fortified, 1 serving | 1.3 mg |
| Oats, instant, fortified, cooked, 1 cup | 1.1 mg |
| Yogurt, plain, fat free, 1 cup | 0.6 mg |
| Milk, 2% fat, 1 cup | 0.5 mg |
| Almonds, dry roasted, 1 oz | 0.3 mg |
| Cheese, Swiss, 3 oz | 0.3 mg |
| Mushrooms, portabella, grilled, ½ cup | 0.2 mg |
| Quinoa, cooked, 1 cup | 0.2 mg |
| Food and serving | Amount |
|---|---|
| Beef liver, pan fried, 3 oz | 2.9 mg |
| Beef tenderloin steak, grilled, 3 oz | 0.4 mg |
| Clams, cooked, 3 oz | 0.4 mg |
| Egg, whole, scrambled, 1 large | 0.2 mg |
| Rotisserie chicken, breast meat, 3 oz | 0.2 mg |
| Salmon, pink, canned, 3 oz | 0.2 mg |
Riboflavin dissolves in water, so boiling loses about twice as much as steaming or microwaving, and light breaks it down, which is why milk is not usually sold in clear glass1. Amounts per serving from1.
Grains and cereals are fortified with riboflavin in the U.S. and many other countries1.
Bacteria in the large intestine make some free riboflavin that can be absorbed, in amounts that depend on the diet1.
Found in multivitamins, B-complex supplements and riboflavin-only products2.
The same reference table draws the reference lines on your charts in Ayuvo. Needs differ in pregnancy and breastfeeding, which are not covered here.
| Age | Women | Men |
|---|---|---|
| 19–30 | 1.1 mg | 1.3 mg |
| 31–50 | 1.1 mg | 1.3 mg |
| 51–70 | 1.1 mg | 1.3 mg |
| 71+ | 1.1 mg | 1.3 mg |
RDA (Recommended Dietary Allowance) is the daily amount that meets the needs of nearly all healthy people. Per day, for adults1.
Signs like these have many possible causes. They are a reason to talk to a clinician, not to self-treat.
Deficiency is extremely rare in the U.S., and people who have it usually lack other nutrients too; vegans and people who eat little dairy are more at risk1.
No adverse effects have been reported from high intakes from food or supplements, possibly because the gut absorbs only limited amounts, so no upper limit is set1.
Riboflavin status is not routinely measured in healthy people. The erythrocyte glutathione reductase activity coefficient (EGRAC) compares a red blood cell enzyme with and without added FAD; it is a stable, sensitive measure, but the best cutoffs are uncertain1.
| EGRAC | What it may mean |
|---|---|
| 1.2 or less | Usually read as adequate |
| 1.2–1.4 | Marginal deficiency |
| Above 1.4 | Deficiency |
Labs use different units and ranges. Your clinician reads a result alongside your history and other tests.
Riboflavin is in many multivitamins and B-complex products and is sold on its own; most supplements use the free form1.
The form in most supplements; free riboflavin is about as bioavailable as the FMN and FAD in food1.
Another name for FMN, one of the two coenzyme forms; used in some supplements1.
Some hold much more riboflavin than recommended, but the body cannot absorb large amounts at once2.
Supplements can interact with medicines. Talk to a clinician or pharmacist before you start one, especially at high doses.
Riboflavin is a naturally yellow, fluorescent compound. When a supplement provides more than the body needs, the extra that is absorbed leaves in urine and can colour it bright yellow. Discoloured urine is described as a minimal side effect.
Vegans and people who eat little dairy are more likely to fall short, because milk, yogurt, cheese and eggs are major sources. Fortified cereals and oats, almonds, mushrooms, spinach and quinoa also provide riboflavin.
Some small studies found fewer migraine attacks with high-dose riboflavin supplements and others did not. Some headache specialist groups list it as a possible option for prevention because side effects are few. Anyone considering it should talk to a clinician first.
Food logging does not estimate riboflavin, so Ayuvo tracks it from supplements you log in Medications, and from Apple Health on iPhone or Health Connect on Android when another app saves it there. Charts by day, week, month and year use the reference lines from this page, personalised by age and sex where they differ. Free, with no account.
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Facts on this page come from these sources, checked on the dates shown. Intake numbers come from Ayuvo's shared reference table, which cites the sources marked for them.
General information, not medical advice. This guide is for healthy adults and does not cover pregnancy, breastfeeding, children or medical conditions. It cannot diagnose or treat anything. Talk to a clinician before starting high-dose supplements, or if you think you may have too little or too much of a nutrient. Spotted an error? Email us.