Pyridoxine (B6)
What is vitamin B6?
Vitamin B6, also known as pyridoxine, is an essential nutrient that supports metabolic processes throughout the body. Vitamin B6 exists in six different forms, called vitamers. These vitamers are pyridoxal, pyridoxine, pyridoxamine, pyridoxal 5’ phosphate (PLP), pyridoxine 5’ phosphate (PNP), and pyridoxamine 5’ phosphate (PMP). PLP is the active form of vitamin B6.1 We can consume vitamin B6 in any of its forms, as all six vitamers are interchangeable in the body. Vitamin B6 is a water-soluble vitamin, which means it is not stored in the body in large amounts. Since our bodies cannot produce vitamin B6, we must get it through food or supplements.
Why we need it
Most of vitamin B6’s functions are attributed to its role as a coenzyme, which is a substance that is required by an enzyme for a reaction to take place. Vitamin B6 is a coenzyme for more than 150 enzymes in the body, including enzymes involved in forming or breaking down amino acids, fatty acids, and glycogen (a form of carbohydrates, stored in the body for energy).1 Vitamin B6 also supports enzymes that help produce neurotransmitters, which are chemical messengers that transmit signals throughout the brain.1 Additionally, vitamin B6 serves as a coenzyme in the production of heme, which is a precursor to hemoglobin (a protein in red blood cells that transports oxygen throughout the body).2
Vitamin B6 can also act as an antioxidant, which is a substance that protects the body against oxidative stress (a phenomenon in which reactive species can damage our cells and contribute to disease). For example, vitamin B6 can scavenge (inactivate) free radicals, thereby protecting against oxidative stress.1
Where it’s found
Vitamin B6 is found in many different foods, including both animal-based and plant-based foods. It is usually present as pyridoxine in plant-based foods, and as pyridoxal or pyridoxamine in animal-based foods. Examples of foods rich in vitamin B6 include:
- Meat and poultry
- Beans
- Fortified cereals
- Whole grains
- Bananas
- Nuts and seeds
- Potatoes
- Spinach
Vitamin B6 can also be taken as a supplement, either by itself or as part of a multivitamin or B-complex supplement. In supplements, vitamin B6 is usually in the form of pyridoxine or PLP.3
Daily requirements
The daily Recommended Dietary Allowance (RDA) for vitamin B6, or the amount that is likely to meet the needs of most healthy people, is 0.1–0.3 milligrams (mg) for infants; 0.5–0.6 mg for children (aged 1 to 8 years); 1.0 mg for male and female adolescents aged 9–13; 1.3 mg /b>for males aged 14–50 years; 1.7 mg for males over 51 years; 1.2 mg for females aged 14–18 years; 1.3 mg for females aged 19–50 years; and 1.5 mg for females over 51 years.4 The RDA increases to 1.9 mg and 2.0 mg for women who are pregnant or breastfeeding, respectively.4
Vitamin B6 deficiency
Vitamin B6 deficiency can affect systems across the entire body. Symptoms of vitamin B6 deficiency may manifest in the skin (e.g., itching, rashes, and blistering), through digestion (e.g., nausea, vomiting, and stomach pain), or through psychological function (e.g., anxiety, confusion, and irritability).4 Additionally, severe vitamin B6 deficiency may increase the risk of other illnesses, such as heart disease and cancer.4
Vitamin B6 deficiency is rare in developed countries, as most people get enough of this vitamin through food. Nonetheless, vitamin B6 deficiency does still occur in some people. Groups that may be at higher risk include individuals with alcoholism (since alcohol interferes with the body’s ability to form active vitamin B6), kidney disease, and malabsorptive conditions like inflammatory bowel disease or celiac disease.2
Can you get too much vitamin B6?
Although rare, vitamin B6 toxicity is possible. Excessive consumption of vitamin B6 may cause sensory neuropathy, a condition that involves nerve damage and loss of sensation throughout the body.4 Other potential symptoms of vitamin B6 toxicity include skin lesions and digestive issues like nausea and heartburn.3
To prevent toxicity, a Tolerable Upper Intake Level (UL) has been established for vitamin B6. The UL for vitamin B6, or the maximum amount that is considered safe, is 100 mg per day for adult men and women.4
Fun facts
Vitamin B6 may help prevent or treat heart disease. This is in part due to the fact that vitamin B6 can lower levels of homocysteine, an amino acid that is a known risk factor for heart disease. Nonetheless, further research is needed to clarify the effectiveness of vitamin B6 for heart disease prevention and management.3
Vitamin B6 is vital for mental health, given its role in producing neurotransmitters. For example, vitamin B6 is involved in the production of serotonin, a neurotransmitter that helps regulate mood and fight against depression.2 Thus, vitamin B6 is important not only for our physical health, but also for our happiness and overall well being.
References
- Ueland, P. M., McCann, A., Midttun, Ø., & Ulvik, A. (2017). Inflammation, vitamin B6 and related pathways. Molecular aspects of medicine, 53, 10–27.
- Parra, M., Stahl, S., & Hellmann, H. (2018). Vitamin B₆ and Its Role in Cell Metabolism and Physiology. Cells, 7(7), 84.
- U.S. Department of Health and Human Services. (2022). Vitamin B6: Fact Sheet for Health Professionals. NIH Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/VitaminB6-HealthProfessional/#h8
- Institute of Medicine. (1998). Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: The National Academies Press.
- Chawla, J., & Kvarnberg, D. (2014). Hydrosoluble vitamins. Handbook of clinical neurology, 120, 891–914.
Dietary supplement
You can use a dietary supplement of Pyridoxine (B6) if you think your diet lacks this nutrient.
Use the list below to check if your diet has enough Pyridoxine (B6) intake.
Food high in Pyridoxine (B6)
This list shows food that are top sources of Pyridoxine (B6) and the quantity of Pyridoxine (B6) in 100g of food
