Vitamin B6, also known as pyridoxine, is a water-soluble vitamin essential for human health. The body cannot produce it, so it must be obtained through diet or supplementation. As a water-soluble vitamin, excess amounts are typically excreted, meaning the body doesn’t store large reserves.
Why B6 is Essential
Vitamin B6 acts as a coenzyme, assisting enzymes in over 100 metabolic reactions. It helps metabolize proteins, carbohydrates, and fats, converting food into energy. This vitamin also aids in synthesizing neurotransmitters like serotonin, dopamine, and GABA, which are crucial for mood and brain function.
Vitamin B6 is also important for forming hemoglobin, the protein in red blood cells that carries oxygen. It supports immune function by promoting antibody and white blood cell production, which fight infections.
Recommended Daily Intake
The Recommended Dietary Allowance (RDA) for vitamin B6 varies by age, sex, and life stage. For most adults aged 19–50 years, the RDA is 1.3 milligrams (mg) per day. This increases for older adults, with men over 50 needing 1.7 mg and women over 50 needing 1.5 mg daily.
Pregnant individuals require 1.9-2.0 mg per day, and breastfeeding individuals need approximately 2.0 mg daily. Children’s requirements range from 0.4 mg for infants (7-12 months) to 1.0-1.3 mg for adolescents. These guidelines aim to meet the nutritional needs of most healthy people and prevent deficiency.
Sources of B6
Vitamin B6 is widely available in a variety of foods, making it generally achievable to meet daily requirements through a balanced diet. Sources include poultry (chicken, turkey) and fish (salmon, tuna). Starchy vegetables like potatoes and fruits like bananas also contribute significantly.
Legumes such as chickpeas and nuts are good plant-based sources. Many breakfast cereals are fortified with vitamin B6, offering another accessible option. While a diverse diet is the preferred method, B6 is also available in dietary supplements for those who may need additional intake.
When More B6 Might Be Needed
Some individuals may need more vitamin B6 than recommended or face a higher deficiency risk. Symptoms of B6 deficiency include skin rashes and neurological issues like peripheral neuropathy, causing numbness or tingling in the hands and feet. Other signs can involve confusion, depression, irritability, weakened immune function, and certain types of anemia.
Populations with an elevated risk of B6 deficiency include those with impaired renal function (e.g., kidney disease) and malabsorption syndromes (e.g., celiac disease, inflammatory bowel disease). People with alcohol dependence and those taking certain medications (e.g., some antiepileptic drugs, tuberculosis treatments) may also experience reduced B6 levels. Consulting a healthcare professional is important before increasing B6 intake through supplements, especially for specific health conditions.
Potential Harms of Excessive B6
While food sources of vitamin B6 rarely cause adverse effects, excessive supplement intake can lead to toxicity. The Tolerable Upper Intake Level (UL) for adults, the maximum daily intake unlikely to cause harm, is generally 100 mg per day. However, some European authorities set a lower UL of 12 mg daily for adults, including pregnant and lactating women, due to neurotoxicity concerns.
Symptoms of B6 toxicity are mainly neurological, including severe peripheral neuropathy with nerve damage causing numbness, tingling, and pain in the extremities. Individuals may also experience loss of muscle control, severe sensory abnormalities, skin lesions, and photosensitivity. These effects are almost exclusively linked to high-dose supplementation, often exceeding the UL, and usually improve upon discontinuing supplements.