Most adults need 1.3 mg of vitamin B6 per day. That number shifts slightly depending on your age, sex, and whether you’re pregnant or breastfeeding, but for anyone between 19 and 50, 1.3 mg is the target set by the National Institutes of Health. It’s an easy amount to get from food alone, though supplements are common for specific health reasons.
Recommended Intake by Age and Sex
Children need less B6 than adults, and requirements climb gradually through adolescence. After age 50, the recommendation increases slightly for both men and women. Here’s the full breakdown:
- Infants (0–12 months): 0.1 to 0.3 mg
- Children 1–3 years: 0.5 mg
- Children 4–8 years: 0.6 mg
- Children 9–13 years: 1.0 mg
- Teens 14–18: 1.3 mg for males, 1.2 mg for females
- Adults 19–50: 1.3 mg for both men and women
- Adults 51+: 1.7 mg for men, 1.5 mg for women
- Pregnant women: 1.9 mg
- Breastfeeding women: 2.0 mg
The slight bump after 50 reflects changes in how the body absorbs and uses B6 as it ages. If you’re eating a varied diet with poultry, fish, potatoes, and some fruit, you’re likely hitting these numbers without thinking about it.
What Vitamin B6 Actually Does
B6 is involved in over 100 enzyme reactions in your body, most of them related to processing protein. It also plays a role in making neurotransmitters (the chemical messengers your brain uses to regulate mood, sleep, and focus), producing hemoglobin for red blood cells, and supporting immune function. Your body can’t make B6 on its own, so it has to come from food or supplements.
Higher Doses for Specific Conditions
Some people take more than the standard recommendation for particular health reasons. These therapeutic doses go beyond what you’d get from food, and they come with different considerations.
Morning Sickness
B6 is one of the first-line options for pregnancy-related nausea. A typical dose is 10 to 25 mg taken three times a day. That’s well above the 1.9 mg pregnancy RDA, but it’s a recognized treatment approach. The general guidance is to stay under 200 mg daily during pregnancy unless directed otherwise by a healthcare provider.
Homocysteine Levels and Heart Health
Homocysteine is an amino acid in your blood, and elevated levels are linked to higher cardiovascular risk. B6 works alongside folate and B12 to help break homocysteine down. A 2024 systematic review in Nutrition Reviews found that the most effective combination for lowering homocysteine in healthy adults was 1 mg of folate, 7.2 mg of B6, and 20 micrograms of B12. That combination ranked first for efficacy across multiple subgroup analyses, including in men specifically and in people whose homocysteine was already in normal ranges.
Best Food Sources
B6 is widely available in both animal and plant foods. Some of the richest sources per serving include chickpeas, beef liver, yellowfin tuna, salmon, chicken breast, and potatoes. A single cup of canned chickpeas provides about 1.1 mg, nearly the full daily requirement for most adults. A serving of salmon or tuna gets you close to 1 mg. Even a medium banana or a cup of fortified cereal contributes meaningfully.
Because B6 is water-soluble, some of it leaches out during cooking, especially boiling. Roasting, baking, or steaming preserves more of the vitamin than submerging food in water.
The Upper Limit and Risk of Nerve Damage
The tolerable upper intake level for adults is set at 100 mg per day. But that number may give a false sense of security. A review by Australia’s Therapeutic Goods Administration found that peripheral neuropathy, a type of nerve damage causing numbness, tingling, or pain in the hands and feet, can occur at doses under 50 mg. In their review of 32 cases, 66% involved daily doses of 50 mg or less.
The TGA’s conclusion was striking: there is no established minimum dose, minimum duration, or specific risk factor that reliably predicts when nerve damage will occur. Some people develop symptoms at relatively modest supplement doses, while others tolerate higher amounts without problems. The nerve damage is usually reversible once supplementation stops, but not always completely.
This is why taking high-dose B6 supplements “just in case” is a poor strategy. Unlike some vitamins where excess is simply excreted, B6 accumulation can cause real harm.
Pyridoxine vs. P5P Supplements
Most B6 supplements contain pyridoxine hydrochloride, the inactive form. Your body has to convert it into its active form (called P5P, or pyridoxal-5′-phosphate) before it can use it. Some supplements sell P5P directly, marketed as being more readily usable by the body.
There’s an interesting wrinkle here. Research published in Toxicology in Vitro found that high concentrations of the inactive pyridoxine form actually compete with and block the active form in your cells. In other words, flooding your body with pyridoxine doesn’t just fail to help at a certain point; it can actively interfere with B6 function. This is sometimes called the “vitamin B6 paradox.” Pyridoxine also has limited ability to cross into the brain, which means excessive supplementation could disrupt signaling in peripheral nerves while leaving central nervous system levels unchanged.
For people taking B6 at or near the RDA, the form likely doesn’t matter much. But if you’re taking higher therapeutic doses, the distinction between pyridoxine and P5P becomes more relevant.
Signs You Might Not Be Getting Enough
True B6 deficiency is uncommon in people eating a varied diet, but it does happen, particularly in older adults, people with alcohol use disorder, and those with certain digestive conditions that impair absorption. Mild deficiency can cause cracked or sore lips, a swollen tongue, irritability, confusion, and weakened immune response. More severe deficiency leads to a specific type of anemia where red blood cells are small and pale, and in rare cases, seizures.
B6 deficiency rarely occurs in isolation. It typically shows up alongside low levels of B12 and folate, since these vitamins work closely together. A blood test measuring the active form of B6 in your plasma can confirm whether your levels are adequate.