Vitamin B complex: how much to take
A B complex combines several B vitamins in one pill. Amounts vary a lot between brands, and B6 is the one to watch.
Calculator Official intake Study doses Best form Safety Sources
Official daily intake
Values per B vitamin for adults (your row is highlighted after you set your profile):
Thiamin (B1)
EFSA (European Food Safety Authority)
PRI (population reference intake)
Safe upper limit: not set
No safe limit set (not enough data).
EFSA sets thiamin per energy eaten (0.1 mg per MJ), so there is no single daily number.
NIH / NASEM (United States)
RDA (recommended dietary allowance)
| Men | 1.2 mg |
|---|---|
| Women | 1.1 mg |
| Pregnancy | 1.4 mg |
| Breastfeeding | 1.4 mg |
Safe upper limit: not set
No safe limit set.
Source: National Academies (NASEM) 2019
Riboflavin (B2)
EFSA (European Food Safety Authority)
PRI (population reference intake)
| Men | 1.6 mg |
|---|---|
| Women | 1.6 mg |
| Pregnancy | 1.9 mg |
| Breastfeeding | 2 mg |
Safe upper limit: not set
No safe limit set (not enough data).
NIH / NASEM (United States)
RDA (recommended dietary allowance)
| Men | 1.3 mg |
|---|---|
| Women | 1.1 mg |
| Pregnancy | 1.4 mg |
| Breastfeeding | 1.6 mg |
Safe upper limit: not set
No safe limit set.
Source: National Academies (NASEM) 2019
Niacin (B3)
EFSA (European Food Safety Authority)
PRI (population reference intake)
Safe upper limit: not set
EFSA safe limit depends on the form: 10 mg for nicotinic acid, 900 mg for nicotinamide. Pick the form below.
EFSA sets niacin per energy eaten (1.6 mg NE per MJ), so there is no single daily number.
NIH / NASEM (United States)
RDA (recommended dietary allowance)
| Men | 16 mg |
|---|---|
| Women | 14 mg |
| Pregnancy | 18 mg |
| Breastfeeding | 17 mg |
Safe upper limit: 35 mg a day
Safe limit applies to niacin from supplements and fortified foods (flushing).
Source: National Academies (NASEM) 2019
Pantothenic acid (B5)
EFSA (European Food Safety Authority)
AI (adequate intake)
| Men | 5 mg |
|---|---|
| Women | 5 mg |
| Pregnancy | 5 mg |
| Breastfeeding | 7 mg |
Safe upper limit: not set
No safe limit set (not enough data).
NIH / NASEM (United States)
AI (adequate intake)
| Men | 5 mg |
|---|---|
| Women | 5 mg |
| Pregnancy | 6 mg |
| Breastfeeding | 7 mg |
Safe upper limit: not set
No safe limit set.
Source: National Academies (NASEM) 2019
Vitamin B6
EFSA (European Food Safety Authority)
PRI (population reference intake)
| Men | 1.7 mg |
|---|---|
| Women | 1.6 mg |
| Pregnancy | 1.8 mg |
| Breastfeeding | 1.7 mg |
Safe upper limit: 12 mg a day
EFSA lowered the B6 safe limit to 12 mg in 2023 (nerve damage at high long-term intakes).
NIH / NASEM (United States)
RDA (recommended dietary allowance)
| Men 18-50 | 1.3 mg |
|---|---|
| Men 51+ | 1.7 mg |
| Women 18-50 | 1.3 mg |
| Women 51+ | 1.5 mg |
| Pregnancy | 1.9 mg |
| Breastfeeding | 2 mg |
Safe upper limit: 100 mg a day
Source: National Academies (NASEM) 2019
Biotin (B7)
EFSA (European Food Safety Authority)
AI (adequate intake)
| Men | 40 µg |
|---|---|
| Women | 40 µg |
| Pregnancy | 40 µg |
| Breastfeeding | 45 µg |
Safe upper limit: not set
No safe limit set (not enough data).
NIH / NASEM (United States)
AI (adequate intake)
| Men | 30 µg |
|---|---|
| Women | 30 µg |
| Pregnancy | 30 µg |
| Breastfeeding | 35 µg |
Safe upper limit: not set
No safe limit set.
Source: National Academies (NASEM) 2019
Folate (B9)
EFSA (European Food Safety Authority)
PRI (population reference intake)
| Men | 330 µg |
|---|---|
| Women | 330 µg |
| Pregnancy | 600 µg |
| Breastfeeding | 500 µg |
Safe upper limit: 1,000 µg a day
Safe limit is for folic acid and methylfolate from supplements and fortified foods, counted as plain µg (not DFE).
NIH / NASEM (United States)
RDA (recommended dietary allowance)
| Men | 400 µg |
|---|---|
| Women | 400 µg |
| Pregnancy | 600 µg |
| Breastfeeding | 500 µg |
Safe upper limit: 1,000 µg a day
Safe limit is for synthetic folic acid, counted as plain µg (not DFE).
NIH advises women who could become pregnant to take 400 µg folic acid a day from supplements or fortified food.
Source: National Academies (NASEM) 2019
Targets are in µg DFE (dietary folate equivalents). 1 µg folic acid taken with food counts as about 1.7 µg DFE.
Vitamin B12
EFSA (European Food Safety Authority)
AI (adequate intake)
| Men | 4 µg |
|---|---|
| Women | 4 µg |
| Pregnancy | 4.5 µg |
| Breastfeeding | 5 µg |
Safe upper limit: not set
No adverse effects defined, so no safe limit.
NIH / NASEM (United States)
RDA (recommended dietary allowance)
| Men | 2.4 µg |
|---|---|
| Women | 2.4 µg |
| Pregnancy | 2.6 µg |
| Breastfeeding | 2.8 µg |
Safe upper limit: not set
No safe limit set.
Over 50, NIH advises getting B12 mainly from fortified food or a supplement (absorption from food drops).
Source: National Academies (NASEM) 2019
Doses used in studies
These are doses tested in research, not personal advice. Some exceed the upper limit because they were short courses or given under medical care.
B complex is checked per vitamin. Enter each amount from your label.
Best form and why
No best form
Why: Pick a B complex with vitamin B6 at or below 12 mg (the EFSA safe limit) and folic acid at 400 µg or less. Doses of 50 to 100 mg of each B vitamin are rarely needed.
Food sources
Whole grains, meat, eggs, dairy, legumes, leafy greens.
Interactions
See the single-vitamin pages: biotin affects lab tests, folic acid can mask B12 deficiency.
Safety
Many "B-50" and "B-100" products contain 50 to 100 mg B6, several times the EFSA safe limit of 12 mg.
Pregnant, breastfeeding, on medication, or managing a health condition? Check with a doctor or pharmacist before starting a supplement.
Sources
- Official reference EFSA (2017). Dietary Reference Values for nutrients: Summary report. EFSA Supporting Publications
- Official reference EFSA (2025). Overview on Tolerable Upper Intake Levels as derived by the SCF and the EFSA NDA Panel (version 11, August 2025). EFSA
- Official reference National Academies (NASEM) (2019). Dietary Reference Intakes: RDA, AI and UL tables (via NIH ODS Nutrient Recommendations). Food and Nutrition Board
Values checked: November 12, 2026.
Fact sheets on other sites
Independent summaries to read alongside this page. PillMath is not affiliated with these sites.