Vitamin B6, also known as pyridoxine, is a water-soluble vitamin that your body needs for several functions.
It’s significant to protein, fat and carbohydrate metabolism and the creation of red blood cells and neurotransmitters (1).
Your body cannot produce vitamin B6, so you must obtain it from foods or supplements.
Most people get enough vitamin B6 through their diet, but certain populations may be at risk for deficiency.
Consuming adequate amounts of vitamin B6 is important for optimal health and may even prevent and treat chronic diseases ().
Here are 9 health benefits of vitamin B6, backed by science.
Vitamin B6 plays an important role in mood regulation.
Vitamin B6 may also play a role in decreasing high blood levels of the amino acid homocysteine, which have been linked to depression and other psychiatric issues (, ).
Several studies have shown that depressive symptoms are associated with low blood levels and intakes of vitamin B6, especially in older adults who are at high risk for B vitamin deficiency (, , ).
One study in 250 older adults found that deficient blood levels of vitamin B6 doubled the likelihood of depression ().
However, using vitamin B6 to prevent or treat depression has not been shown to be effective (, ).
A controlled two-year study in approximately 300 older men who did not have depression at the start found that those taking a supplement with B6, folate (B9) and B12 were not less likely to have depressive symptoms compared to the placebo group ().
Summary Low levels of vitamin B6 in older adults have been linked to depression, but research has not shown that B6 is an effective treatment for mood disorders.
Vitamin B6 may play a role in improving brain function and preventing Alzheimer’s disease, but the research is conflicting.
On the one hand, B6 can decrease high homocysteine blood levels that may increase the risk of Alzheimer’s (, , ).
One study in 156 adults with high homocysteine levels and mild cognitive impairment found that taking high doses of B6, B12 and folate (B9) decreased homocysteine and reduced wasting in some regions of the brain that are vulnerable to Alzheimer’s ().
However, it’s unclear if a decrease in homocysteine translates to improvements in brain function or a slower rate of cognitive impairment.
A randomized controlled trial in over 400 adults with mild to moderate Alzheimer’s found that high doses of B6, B12 and folate decreased homocysteine levels but did not slow decline in brain function compared to a placebo ().
In addition, a review of 19 studies concluded that supplementing with B6, B12 and folate alone or in combination did not improve brain function or reduce the risk of Alzheimer’s ().
More research that looks at the effect of vitamin B6 alone on homocysteine levels and brain function is needed to better understand the role of this vitamin in improving brain health.
Summary Vitamin B6 may prevent a decline in brain function by decreasing homocysteine levels that have been associated with Alzheimer’s disease and memory impairments. However, studies have not proven the effectiveness of B6 in improving brain health.
Due to its role in hemoglobin production, vitamin B6 may be helpful in preventing and treating anemia caused by deficiency ().
Hemoglobin is a protein that delivers oxygen to your cells. When you have low hemoglobin, your cells don’t get enough oxygen. As a result, you may develop anemia and feel weak or tired.
Studies have linked low levels of vitamin B6 with anemia, especially in pregnant women and women of childbearing age (, ).
However, vitamin B6 deficiency is thought to be rare in most healthy adults, so there is limited research on using B6 to treat anemia.
A case study in a 72-year-old woman with anemia due to low B6 found that treatment with the most active form of vitamin B6 improved symptoms ().
Another study found that taking 75 mg of vitamin B6 daily during pregnancy decreased symptoms of anemia in 56 pregnant women who were unresponsive to treatment with iron ().
More research is needed to understand the effectiveness of vitamin B6 in treating anemia in populations other than those at increased risk for B vitamin deficiency, such as pregnant women and older adults
Summary Not getting enough vitamin B6 can lead to low hemoglobin and anemia, so supplementing with this vitamin may prevent or treat these issues.
Vitamin B6 has been used to treat symptoms of premenstrual syndrome, or PMS, including anxiety, depression and irritability.
Researchers suspect that B6 helps with emotional symptoms related to PMS due to its role in creating neurotransmitters that regulate mood.
A three-month study in over 60 premenopausal women found that taking 50 mg of vitamin B6 daily improved PMS symptoms of depression, irritability and tiredness by 69% ().
However, women who received a placebo also reported improved PMS symptoms, which suggests that the effectiveness of the vitamin B6 supplement may have been due in part to a placebo effect ().
Another small study found that 50 mg of vitamin B6 along with 200 mg of magnesium per day significantly reduced PMS symptoms, including mood swings, irritability and anxiety, over the course of one menstrual cycle ().
While these results are promising, they’re limited by small sample size and short duration. More research on the safety and effectiveness of vitamin B6 in improving PMS symptoms is needed before recommendations can be made ().
Summary Some research has indicated that high doses of vitamin B6 may be effective at decreasing anxiety and other mood issues associated with PMS due to its role in creating neurotransmitters.
Vitamin B6 has been used for decades to treat nausea and vomiting during pregnancy.
In fact, it’s an ingredient in Diclegis, a medication commonly used to treat morning sickness ().
Researchers are not entirely sure why vitamin B6 helps with morning sickness, but it may be because adequate B6 plays several vital roles in ensuring a healthy pregnancy ().
A study in 342 women in their first 17 weeks of pregnancy found that a daily supplement of 30 mg of vitamin B6 significantly reduced feelings of nausea after five days of treatment, compared to a placebo ().
Another study compared the impact of ginger and vitamin B6 on reducing episodes of nausea and vomiting in 126 pregnant women. The results showed that taking 75 mg of B6 each day decreased nausea and vomiting symptoms by 31% after four days ().
These studies suggest that vitamin B6 is effective in treating morning sickness even in durations of less than one week.
If you’re interested in taking B6 for morning sickness, speak with your doctor before starting any supplements.
Summary Vitamin B6 supplements in doses of 30–75 mg a day have been used as an effective treatment for nausea and vomiting during pregnancy.
Vitamin B6 may prevent clogged arteries and minimize heart disease risk.
Research shows that people with low blood levels of vitamin B6 have almost double the risk of getting heart disease compared to those with higher B6 levels ().
This is likely due to the role of B6 in decreasing elevated homocysteine levels associated with several disease processes, including heart disease (, , ).
One study found that rats deficient in vitamin B6 had higher blood levels of cholesterol and developed lesions that could cause artery blockages after being exposed to homocysteine, compared to rats with adequate B6 levels ().
Human research also shows a beneficial effect of B6 in preventing heart disease.
A randomized controlled trial in 158 healthy adults who had siblings with heart disease divided participants into two groups, one that received 250 mg of vitamin B6 and 5 mg of folic acid every day for two years and another that received a placebo ().
The group that took B6 and folic acid had lower homocysteine levels and less abnormal heart tests during exercise than the placebo group, putting them at an overall lower risk of heart disease ().
Summary Vitamin B6 may help reduce high homocysteine levels that lead to narrowing of arteries. This may minimize heart disease risk.
Getting enough vitamin B6 may lower your risk of developing certain types of cancer.
The reason why B6 may help prevent cancer is unclear, but researchers suspect that it’s related to its ability to fight inflammation that may contribute to cancer and other chronic conditions (, ).
A review of 12 studies found that both adequate dietary intake and blood levels of B6 were associated with lower risks of colorectal cancer. Individuals with the highest blood levels of B6 had an almost 50% lower risk of developing this type of cancer ().
Research on vitamin B6 and breast cancer also shows an association between adequate blood levels of B6 and a decreased risk of the disease, especially in postmenopausal women ().
However, other studies on vitamin B6 levels and cancer risk have found no association (, ).
More research that includes randomized trials and not merely observational studies is needed to assess the exact role of vitamin B6 in cancer prevention.
Summary Some observational studies suggest a link between adequate dietary intake and blood levels of vitamin B6 and a decreased risk of certain types of cancer, but more research is needed.
Vitamin B6 may play a role in preventing eye diseases, especially a type of vision loss that affects older adults called age-related macular degeneration (AMD).
Studies have linked high blood levels of circulating homocysteine with an increased risk of AMD (, ).
Since vitamin B6 helps reduce elevated blood levels of homocysteine, getting enough B6 may lower your risk of this disease ().
A seven-year study in over 5,400 female health professionals found that taking a daily supplement of vitamin B6, B12 and folic acid (B9) significantly reduced AMD risk by 35–40%, compared to a placebo ().
While these results suggest that B6 may play a role in preventing AMD, it’s difficult to tell if B6 alone would offer the same benefits.
Research has also linked low blood levels of vitamin B6 to eye conditions that block veins that connect to the retina. A controlled study in over 500 people found that the lowest blood levels of B6 were significantly associated with retinal disorders ().
Summary Vitamin B6 supplements may reduce your risk of age-related macular degeneration (AMD). Additionally, adequate blood levels of B6 may prevent issues that affect the retina. However, more research is needed.
Vitamin B6 may help reduce symptoms associated with rheumatoid arthritis.
The high levels of inflammation in the body that result from rheumatoid arthritis may lead to low levels of vitamin B6 (, ).
However, it’s unclear if supplementing with B6 decreases inflammation in people with this condition.
A 30-day study in 36 adults with rheumatoid arthritis found that 50 mg of vitamin B6 daily corrected low blood levels of B6 but did not decrease the production of inflammatory molecules in the body ().
On the other hand, a study in 43 adults with rheumatoid arthritis that took 5 mg of folic acid alone or 100 mg of vitamin B6 with 5 mg of folic acid daily showed that those who received B6 had significantly lower levels of pro-inflammatory molecules after 12 weeks ().
The contradictory results of these studies may be due to the difference in vitamin B6 dose and study length.
While it appears that high doses of vitamin B6 supplements may provide anti-inflammatory benefits for people with rheumatoid arthritis over time, more research is needed.
Summary Inflammation associated with rheumatoid arthritis may lower blood levels of vitamin B6. Supplementing with high doses of B6 may help correct deficiencies and reduce inflammation, but more research is needed to confirm these effects.
You can get vitamin B6 from food or supplements.
The current recommended daily amount (RDA) for B6 is 1.3–1.7 mg for adults over 19. Most healthy adults can get this amount through a balanced diet that includes vitamin-B6-rich foods like turkey, chickpeas, tuna, salmon, potatoes and bananas (1).
Studies that highlight the use of vitamin B6 to prevent and treat health issues focus on supplements rather than food sources.
Doses of 30–250 mg of vitamin B6 per day have been used in research on PMS, morning sickness and heart disease (, , ).
These amounts of B6 are significantly higher than the RDA and sometimes combined with other B vitamins. It’s difficult to assess if increasing intake of B6 from dietary sources has the same benefits for certain conditions that supplements may provide.
If you’re interested in taking vitamin B6 supplements to prevent or address a health issue, speak to your healthcare provider about the best option for you. In addition, look for a supplement that has been tested for quality by a third party.
Summary Most people can get adequate vitamin B6 through their diet. In some cases, taking higher amounts of vitamin B6 from supplements under the supervision of a doctor may be beneficial.
Getting too much vitamin B6 from supplements can cause negative side effects.
Vitamin B6 toxicity is not likely to occur from food sources of B6. It would be nearly impossible to consume the amount in supplements from diet alone.
Taking more than 1,000 mg of supplemental B6 a day may cause nerve damage and pain or numbness in the hands or feet. Some of these side effects have even been documented after just 100–300 mg of B6 per day ().
For these reasons, the tolerable upper limit of vitamin B6 is 100 mg per day for adults (3, ).
The amount of B6 used to manage certain health conditions rarely exceeds this amount. If you’re interested in taking more than the tolerable upper limit, consult your doctor.
Summary Too much vitamin B6 from supplements can cause damage to nerves and extremities over time. If you’re interested in taking a B6 supplement, speak to your healthcare provider about safety and dosage.
Vitamin B6 is a water-soluble vitamin obtained from food or supplements.
It’s needed for many processes in your body, including creating neurotransmitters and regulating homocysteine levels.
High doses of B6 have been used to prevent or treat certain health conditions, including PMS, age-related macular degeneration (AMD) and nausea and vomiting during pregnancy.
Getting enough B6 through your diet or a supplement is crucial for staying healthy and may have other impressive health benefits as well.