Vitamin B6
Three forms of vitamin B6 are found in food: pyridoxine, pyridoxal, and pyridoxamine. Vitamin B6 is water soluble, and so cannot be stored in body fat. It is absorbed through the intestines. Much of the body’s vitamin B6 is stored in its muscles.
Roles
What does vitamin B6 do?
Vitamin B6 plays a role in:
- Preventing cardiovascular illness;
- Producing insulin;
- Producing histamine (a substance involved in allergic reactions);
- Producing and digesting amino acids (the building blocks of proteins);
- Synthesizing hemoglobin (a molecule that transports oxygen to red blood cells).
A form of vitamin B6 is used to treat symptoms for a number of health issues, such as gestational diabetes, premenstrual syndrome, depression, and asthma.
Needs
Recommended Dietary Allowances for Vitamin B6:
| By Age Group | Recommended Dietary Allowance in mg/Day | |
| Infants | 0 to 6 months | 0,1 |
| 7 to 12 months | 0,3 | |
| Children | 1 to 3 years | 0,5 |
| 4 to 8 years | 0,6 | |
| Preteens | 9 to 13 years | 1,0 |
| Teenage boys | Age 14 to 18 years | 1,3 |
| Teenage girls | Age 14 to 18 ans | 1,2 |
| Adults | Age 19 and over | 1,3 |
| Pregnant women | Ages 14 to 18 | 1,9 |
| Ages 19 to 50 | 1,9 | |
| Nursing mothers | Ages 14 to 18 | 2,0 |
| Ages 19 to 50 | 2,0 | |
Source: DRI, Dietary Reference Intakes: The Essential Guide to Nutrient Requirements 2006, p.182.
Sources
The best source of vitamin B6 is enriched, ready-to-serve cereals. Balanced meals composed mainly of meat, fish, or poultry; white potatoes and other starchy vegetables; and fruit (except citrus) also contain vitamin B6. Beef liver and offal and highly enriched soy-based meat substitutes are also excellent sources of this vitamin.
| Foods | Portion Size | Vitamin B6 |
| Roast turkey drumstick | 100g (3½oz) | 1,3mg |
| Baked yellowfin tuna | 100g (3½oz) | 1,0mg |
| Sautéed or braised beef liver | 100g (3½oz) | 1,0mg |
| Baked skipjack tuna | 100g (3½oz) | 1,0mg |
| Sautéed lamb or veal liver | 100g (3½oz) | 0,9-1,0mg |
| Poached or grilled Atlantic salmon (pink or chum) | 100g (3½oz) | 0,6-0,9mg |
| Dehydrated salt Atlantic cod | 100g (3½oz) | 0,9mg |
| Steamed or boiled octopus | 100g (3½oz) | 0,7mg |
| Baked potato with peel | 1 medium (175g) | 0,6mg |
| Canned chickpeas | 125ml (1/2 cup) | 0,6mg |
| Dry roasted pistachios | 60ml (1/4 cup) | 0,5mg |
| Roast chicken, meat only | 100g (3½oz) | 0,5mg |
| Flaxseed | 60ml (1/4 cup) | 0,4mg |
| Banana | 1 medium | 0,4mg |
| Dried or cooked shitake mushrooms | 4 to 10 mushrooms (40g ou 125ml) | 0,1-0,4mg |
| 100% bran breakfast cereals (e.g., All-Bran) | 30g | 0,3mg |
| Whole, roast, grilled, or dehydrated sesame seeds | 60ml (1/4 cup) | 0,3mg |
| Dry or oil-roasted sunflower seeds | 60ml (1/4 cup) | 0,3mg |
| Cooked or uncooked prunes | 60ml (1/4 cup) | 0,2-0,3mg |
| Dry-roasted, unbleached hazelnuts and filberts | 60ml (1/4 cup) | 0,2mg |
Source: Health Canada, Canadian Nutrient File, versions 2001b and 2005; United States Department of Agriculture (USDA), National Nutrient Database for Standard Reference.
Deficiency
Minor vitamin B6 deficiency is relatively common. It appears in newborns whose diets lack the vitamin. It is also found in some women who take oral contraceptives, alcoholics, and smokers. Deficiency is not observed unless daily intake is 0.5 mg/day or less.
Some illnesses may reduce the amount of vitamin B6 found in the blood, such as:
- Asthma;
- Kidney disease;
- Diabetes;
- Sickle-cell anemia;
- Hodgkin’s disease (cancer of the lymph nodes).
Signs of vitamin B6 deficiency:
- Seborrhoeic dermatitis;
- Cracked lips;
- Nausea and diarrhea;
- Loss of appetite;
- Depression and confusion (extreme cases);
- Epileptic seizures (extreme cases).
Adverse effects
No harmful effects have been tied to excessive vitamin B6 intake from food sources. However, excessive intake of more than 200 mg/day resulting from a pyridoxine supplement used to treat a number of complaints such as carpal tunnel syndrome, painful neuropathy, premenstrual syndrome, asthma, sickle-cell anemia, and epileptic seizures may trigger certain symptoms.
Signs of excess vitamin B6:
- Skin lesions;
- Sensory neuropathy.
Interactions
Natural health products or vitamin supplements:
- none;
Drugs that may result in vitamin B6 deficiency:
- Medication for tuberculosis;
- Some oral contraceptives;
- Some medications used to treat rheumatoid arthritis, asthma, hypertension, depression, and some antibiotics;
- Vitamin B6 decreases the therapeutic effect of some medications used to treat Parkinson’s disease and epilepsy;
- Combining vitamin B6 and amiodarone increases photosensitivity (sensitivity to light).
Additional information
Speak with your pharmacist if you plan to take vitamin B6 supplements. Your pharmacist can help you choose the solution that’s best for you based on your health and any drugs you take.
Other names
Vitamin B6, Pyridoxine, Pyridoxal, Pyridoxamine