B2 Supplement Guide
Evidence-based information on B2 benefits, dosage, safety, and food sources — sourced from NIH, FDA, and PubMed.
Our assessment
The evidence shows that B2 (riboflavin) is a well-tolerated and essential vitamin. Our assessment is that it plays a critical role in your body's energy production and detoxification systems, and the data indicates a very strong safety profile NIH ODS ↗.
How it works
Think of B2 as a cellular power plant operator. It works by enhancing mitochondrial efficiency and biogenesis, which means it helps your cells' energy centers work better and multiply. B2 also supports cellular ATP synthesis (your body's main energy currency) and enhances the beta-oxidation of fatty acids for energy. Additionally, it supports your liver's cytochrome P450 detoxification pathways NIH ODS ↗.
Safety profile
The safety profile for B2 is excellent. The NIH ODS states that riboflavin has not been shown to cause any harm. Data on specific side effects from the FDA is not available. Riboflavin is not known to interact with any medications, though you should always tell your doctor about any supplements you take NIH ODS ↗.
Our recommendation
Our recommendation is that B2 is a very safe supplement to consider, especially if you are looking to support your energy metabolism. Since it is water-soluble, any excess is typically excreted in your urine. Start with a standard dose found in a B-complex or as a standalone 100 mg supplement, and be aware that it may turn your urine a bright yellow color, which is harmless NIH ODS ↗.
AI-assisted analysis based on NIH ODS, FDA, and PubMed data. Citations are linked to original sources.
Recommended Dosage
| Life Stage | Recommended Amount |
|---|---|
| Birth to 6 months | 0.3 mg |
| Infants 7–12 months | 0.4 mg |
| Children 1–3 years | 0.5 mg |
| Children 4–8 years | 0.6 mg |
| Children 9–13 years | 0.9 mg |
| Teen boys 14–18 years | 1.3 mg |
| Teen girls 14–18 years | 1.0 mg |
| Men | 1.3 mg |
| Women | 1.1 mg |
| Pregnant teens and women | 1.4 mg |
| Breastfeeding teens and women | 1.6 mg |
Source: National Academies of Sciences, Engineering, and Medicine. Always consult your healthcare provider for personalized dosage recommendations.
Drug Interactions
Riboflavin is not known to interact with any medications. However, it's always important to tell your doctor, pharmacist , and other health care providers about any dietary supplements and prescription or over-the-counter medicines you take. They can tell you if the dietary supplements might interact with your medicines or if the medicines might interfere with how your body absorbs, uses, or breaks down nutrients .
Check All InteractionsFood Sources
Riboflavin is found naturally in some foods and is added to many fortified foods. You can get recommended amounts of riboflavin by eating a variety of foods, including the following: Eggs, organ meats (such as kidneys and liver ), lean meats, and low-fat milk Some vegetables (such as mushrooms and spinach) Fortified cereals, bread, and grain products
Complete food source guideHealth Goals This Supplement Supports
Frequently Asked Questions
How much B2 should I take daily?
Refer to the Recommended Dosage table above. Individual needs vary by age, gender, and health status. Always follow the dosage on your supplement label and consult your healthcare provider.
What are the side effects of B2?
Riboflavin has not been shown to cause any harm.
Can I get enough B2 from food alone?
Riboflavin is found naturally in some foods and is added to many fortified foods. You can get recommended amounts of riboflavin by eating a variety of foods, including the following: Eggs, organ meats (such as kidneys and liver ), lean meats, and low-fat milk Some vegetables (such as mushrooms and s
Does B2 interact with medications?
Riboflavin is not known to interact with any medications. However, it's always important to tell your doctor, pharmacist , and other health care providers about any dietary supplements and prescription or over-the-counter medicines you take. They can tell you if the dietary supplements might interac