Riboflavin (Vitamin B2)
Also known as Vitamin B2
Riboflavin is a water-soluble B vitamin at the center of energy production from food. It also helps the body use other B vitamins and acts in antioxidant defense.
Why it matters
What it does in your body
- Energy metabolism
- Coenzyme (as FAD and FMN) in cellular reactions
- Helps convert vitamin B6 and folate into active forms
- Antioxidant defense (glutathione recycling)
- Normal growth and red blood cell production
By age, sex, and life stage
How much you need
Values are RDAs except for infants, which are Adequate Intakes (AI). Requirements are given in mg/day and rise with age and during pregnancy and lactation.
Recommended intake across life
in mg/dayBars scale to the highest recommendation shown. Where men and women differ, both values are listed.
Full reference table
| Life stage | Male | Female |
|---|---|---|
| Infants 0-6 mo | 0.3 (AI) | 0.3 (AI) |
| Infants 7-12 mo | 0.4 (AI) | 0.4 (AI) |
| Children 1-3 | 0.5 | 0.5 |
| Children 4-8 | 0.6 | 0.6 |
| Children 9-13 | 0.9 | 0.9 |
| Teens 14-18 | 1.3 | 1.0 |
| Adults 19+ | 1.3 | 1.1 |
| Pregnancy | n/a | 1.4 |
| Lactation | n/a | 1.6 |
Values in mg/day. AI marks an Adequate Intake, used when there is not enough evidence for a formal recommendation.
What moves the number
What changes your needs
Age
Needs rise from 0.5 mg/day in early childhood to 1.3 mg/day (men) and 1.1 mg/day (women) in adulthood.
Sex
Adult men need 1.3 mg/day and adult women need 1.1 mg/day.
Body weight / size
Because riboflavin supports energy metabolism, needs scale modestly with body size.
Pregnancy and lactation
Pregnancy raises the need to 1.4 mg/day and lactation to 1.6 mg/day.
Diet pattern
Vegans and people who consume little milk or dairy are more likely to fall short and may need to plan intake carefully.
Running low
Signs you might not get enough
Most at risk: Vegans and people with little dairy intake, vegetarian athletes, pregnant or lactating women with limited meat and dairy intake, and people with the rare inherited riboflavin transporter deficiency.
Too much
Can you get too much?
Riboflavin from food and supplements at many times the RDA shows no observable toxicity. High doses may turn the urine bright yellow, which is harmless.
Where to get it
Best food sources
The bottom line
Milk, yogurt, eggs, lean meats, and fortified grains supply plenty of riboflavin. Adults need 1.1 to 1.3 mg/day, and there is no known risk from getting too much.
Track riboflavin (vitamin b2) automatically
Riboflavin (Vitamin B2) is one of the 92 nutrients Vora reads from a photo of your meal, so you can see where you stand without weighing or logging by hand.
Sources and method
The recommended intakes, upper limits, and food-source amounts on this page come from the primary references below. Numbers were checked against the current NIH Office of Dietary Supplements fact sheets and the Institute of Medicine (now the National Academies) Dietary Reference Intakes.
- NIH Office of Dietary Supplements, Riboflavin Fact Sheet for Health Professionals
- Institute of Medicine (IOM/NASEM), Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (1998)
This page is for general education, not medical advice. Reference intakes are population averages for healthy people and do not replace guidance from your doctor or a registered dietitian, especially if you are pregnant, managing a health condition, or considering supplements.