B6 vitamins side effects

Vitamin B6

Generic Name: pyridoxine (vitamin B6) (PIR ih DOX een)
Brand Name: Vitamin B6

Medically reviewed by Drugs.com on Apr 25, 2019 – Written by Cerner Multum

  • Overview
  • Side Effects
  • Dosage
  • Interactions
  • Pregnancy
  • Reviews
  • More

What is Vitamin B6?

Vitamin B6 is vitamin B6. Vitamins occur naturally in foods such as meat, poultry, nuts, whole grains, bananas, and avocados. Vitamin B6 is important for many processes in the body.

Vitamin B6 is used to treat or prevent vitamin B6 deficiency. It is also used to treat a certain type of anemia (lack of red blood cells). This medicine injection is also used to treat some types of seizure in babies.

Vitamin B6 taken by mouth (oral) is available without a prescription. Injectable this medicine must be given by a healthcare professional.

Vitamin B6 may also be used for purposes not listed in this medication guide.

Important Information

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Before taking this medicine

You should not use Vitamin B6 if you have ever had an allergic reaction to it.

Ask a doctor or pharmacist if it is safe for you to use Vitamin B6 if:

  • you have any other medical conditions;

  • you take other medications or herbal products; or

  • you are allergic to any drugs or foods.

To make sure you can safely receive injectable Vitamin B6, tell your doctor if you have heart disease or kidney disease.

Ask a doctor before using this medicine if you are pregnant or breast-feeding. Your dose needs may be different. High doses of pyridoxine can harm a nursing baby.

Do not give this medicine to a child without medical advice.

How should I use Vitamin B6?

Follow all directions on your prescription label. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Vitamin B6 tablets are taken by mouth. Injectable this medicine is injected into a muscle or into a vein through an IV. You may be shown how to use injections at home. Do not give yourself this medicine if you do not understand how to use the injection and properly dispose of needles, IV tubing, and other items used.

The recommended dietary allowance of pyridoxine increases with age. Follow your healthcare provider’s instructions. You may also consult the Office of Dietary Supplements of the National Institutes of Health, or the U.S. Department of Agriculture (USDA) Nutrient Database (formerly “Recommended Daily Allowances”) listings for more information.

Vitamin B6 may be only part of a complete program of treatment that also includes a special diet. Follow the diet plan created for you by your doctor or nutrition counselor. Get familiar with the list of foods you should eat or avoid to help control your condition.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Use the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not Use extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using Vitamin B6?

Follow your doctor’s instructions about any restrictions on food, beverages, or activity.

Vitamin B6 side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • decreased sensation to touch, temperature, and vibration;

  • loss of balance or coordination;

  • numbness in your feet or around your mouth;

  • clumsiness in your hands; or

  • feeling tired.

Common side effects may include:

  • nausea;

  • headache;

  • drowsiness; or

  • mild numbness or tingling.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Vitamin B6?

Other drugs may interact with pyridoxine, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Copyright 1996-2018 Cerner Multum, Inc. Version: 2.04.

Medical Disclaimer

More about Vitamin B6 (pyridoxine)

  • Side Effects
  • During Pregnancy
  • Dosage Information
  • Drug Interactions
  • Compare Alternatives
  • En Español
  • 1 Review
  • Drug class: vitamins

Consumer resources

Other brands: Aminoxin

Professional resources

  • Pyridoxine Hydrochloride (AHFS Monograph)
  • … +1 more

Related treatment guides

  • Seizures
  • Anemia
  • Dietary Supplementation
  • Drug Induced Vitamin/Mineral Deficiency
  • Nausea/Vomiting


Vitamin B6 (Pyridoxine)

Also listed as:

Table of Contents > Supplements > Vitamin B6 (Pyridoxine)

Overview Dietary Sources Available Forms How to Take It Precautions Possible Interactions Supporting Research

Vitamin B6, also called pyridoxine, is one of 8 B vitamins. All B vitamins help the body convert food (carbohydrates) into fuel (glucose), which is used to produce energy. These B vitamins, often referred to as B-complex vitamins, also help the body metabolize fats and protein. B-complex vitamins are needed for healthy skin, hair, eyes, and liver. They also help the nervous system function properly.

All B vitamins are water soluble, meaning the body does not store them.

Vitamin B6 helps the body make several neurotransmitters, chemicals that carry signals from one nerve cell to another. It is needed for normal brain development and function, and helps the body make the hormones serotonin and norepinephrine, which influence mood, and melatonin, which helps regulate the body clock.

Along with vitamins B12 and B9 (folic acid), B6 helps control levels of homocysteine in the blood. Homocysteine is an amino acid that may be associated with heart disease. Your body needs B6 in order to absorb vitamin B12 and to make red blood cells and cells of the immune system.

It is rare to have a significant deficiency of B6, although studies indicate many people may be mildly deficient, especially children and the elderly. Certain medications can also cause low levels of B6 in the body. Symptoms of serious deficiency include:

  • Muscle weakness
  • Nervousness
  • Irritability
  • Depression
  • Difficulty concentrating
  • Short-term memory loss

Heart disease

It is not clear how vitamin B6 might affect heart disease. People who do not get enough B6 in their diet have a higher risk of heart disease. And B6 plays a role in lowering levels of homocysteine in the blood. High levels of homocysteine appear to be associated with heart disease. But scientists do not know exactly what the relationship is. They also do not know whether lowering levels of homocysteine will reduce your risk of heart disease. Until more is known, the best action is to get enough B6 through food, and to take supplements if your doctor recommends them.

Nausea and vomiting during pregnancy (morning sickness)

Several studies, including one large double-blind, placebo-controlled study, found that a daily dose of 30 mg of B6 may help reduce morning sickness. However, other studies have found no benefit. If you are pregnant, be sure to ask your doctor before taking any supplements, including vitamin B6.

Age-related macular degeneration (AMD)

One large study found that women who took 50 mg of vitamin B6 daily, along with 1,000 mcg of cyanocobalamin (vitamin B12) and 2,500 mcg of folic acid, reduced their risk of developing AMD, an eye disease that can cause vision loss.


Vitamin B6 helps your body make serotonin, a chemical that influences mood. Low levels of serotonin are associated with depression, and some antidepressant medications work by raising levels of serotonin. Some researchers think that vitamin B6 might help reduce symptoms of depression. More research is needed.

Premenstrual syndrome (PMS)

Although some studies show that vitamin B6 may help improve PMS symptoms, most of these studies were poorly designed. Studies that were well designed found no benefit. Until more research is done, talk with your doctor about whether taking B6 is right for you. Some people who believe B6 is effective for PMS say it may take up to 3 months to see a noticeable change.

Carpal tunnel syndrome

Early studies suggested that B6 might help reduce inflammation and symptoms of carpal tunnel syndrome, however, most well-designed studies have found no such link.

Rheumatoid arthritis (RA)

Low levels of vitamin B6 have been associated with RA. Some studies also suggest that people with RA may need more vitamin B6 than healthy people because chronic inflammation may lower B6 levels. Eating a healthy, balanced diet, and taking a multivitamin is a good idea for anyone who has a chronic illness, such as RA. Talk to your doctor before taking B6 supplements.

Tardive dyskinesia

A few small studies have found that vitamin B6 may improve symptoms of tardive dyskinesia compared to placebo. Tardive dyskinesia is a side effect of long-term use of antipsychotic drugs, and involves involuntary movement of muscles, such as in the tongue, lips, face and jaw, arms, legs, fingers, or toes.

Dietary Sources

Good food sources of vitamin B6 include:

  • Fortified ready-to-eat cereal
  • Chicken
  • Turkey
  • Tuna
  • Salmon
  • Shrimp
  • Beef liver
  • Milk
  • Cheese
  • Lentils
  • Beans
  • Spinach
  • Carrots
  • Brown rice
  • Bran
  • Sunflower seeds
  • Wheat germ
  • Bananas
  • Whole-grain flour

Available Forms

Vitamin B6 can be found in multivitamins, including children’s chewable and liquid drops, B complex vitamins, or can be sold separately. It is available in a variety of forms, including tablets, soft gels, and lozenges. Vitamin B6 is also sold under the names pyridoxal, pyridoxamine, pyridoxine hydrochloride, and pyridoxal-5-phosphate.

How to Take It

People who eat a balanced diet should meet the daily requirement for vitamin B6 without taking a supplement. As with all medications and supplements, check with a health care provider before giving vitamin B6 supplements to a child.

Daily recommendations for dietary vitamin B6 are:



Larger doses have been used in some studies. But you should not take doses above 100 mg per day without a doctor’s supervision. Large doses of B6 may cause nerve damage.


You should take dietary supplements only under the supervision of a knowledgeable health care provider because of the potential for side effects and interactions with medications.

Very high doses, 200 mg or more per day, of vitamin B6 can cause neurological disorders, such as loss of feeling in the legs and imbalance. Stopping high doses usually leads to a complete recovery within 6 months.

There have been rare reports of allergic skin reactions to high doses of vitamin B6 supplements.

Other side effects can include:

  • Sensitivity to sunlight
  • Headache
  • Nausea
  • Abdominal pain
  • Loss of appetite

Possible Interactions

If you are being treated with any of the following medications, you should not use vitamin B6 supplements without talking to your health care provider first.

Medicines that reduce levels of B6 in the body. If you take any of these medications, be sure to get enough B6 in your diet:

  • Cycloserine (Seromycin), used to treat tuberculosis
  • Hydralazine (Apresoline), used to treat high blood pressure
  • Isoniazid, used to treat tuberculosis
  • Penicillamine, used to treat RA
  • Theophylline (TheoDur), used to treat asthma

Antibiotics, tetracycline: All B complex vitamins, including vitamin B6, interfere with the absorption and effectiveness of antibiotic tetracycline. You should take tetracycline at different times from vitamin B6 and other B vitamins.

Antidepressant medications: Taking vitamin B6 supplements may improve the effectiveness of some tricyclic antidepressants such as nortriptyline (Pamelor), especially in elderly people. Other tricyclic antidepressants include amitriptyline (Elavil), desipramine (Norpramin), and imipramine (Tofranil).

On the other hand, antidepressants called monoamine oxidase inhibitors (MAOIs) may reduce blood levels of vitamin B6. Examples of MAOIs include phenelzine (Nardil) and tranylcypromine (Parnate).

Amiodarone (Cordarone): This drug, used to treat an irregular heartbeat, makes your skin more sensitive to sunlight. Taking vitamin B6 along with this medication may increase your risk of sunburn, blistering, or a rash.

Chemotherapy drugs: Vitamin B6 may reduce certain side effects of 5-fluorouracil and doxorubicin, medications used to treat cancer. Talk to your doctor before taking any supplement if you are undergoing chemotherapy.

Erythropoietin (EPO): Erythropoietin therapy, used to treat severe anemia, may decrease vitamin B6 levels in red blood cells.

Levodopa (L-dopa): Vitamin B6 reduces the effectiveness of levodopa, a medication used to treat Parkinson disease. However, it does not seem to have the same effect on the combination of levodopa and carbidopa. Your doctor may be able to determine a dose of B6 that can safely help reduce side effects of levodopa. You should only take vitamin B6 along with levodopa under your doctor’s supervision.

Phenytoin (Dilantin): Vitamin B6 makes phenytoin, a medication used to treat seizures, less effective.

Supporting Research

Alpert JE, Mischoulon D, Nierenberg AA, Fava M. Nutrition and depression: focus on folate. Nutrition. 2000;16:544-581.

Booth GL, Wang EE. Preventive health care, 2000 update: screening and management of hyperhomocysteinemia for the prevention of coronary artery disease events. The Canadian Task Force on Preventive Health Care. CMAJ. 2000;163(1):21-29.

Chiang EP, Selhub J, Bagley PJ, Dallal G, Roubenoff R. Pyridoxine supplementation corrects vitamin B6 deficiency but does not improve inflammation in patients with rheumatoid arthritis. Arthritis Res Ther. 2005;7(6):R1404-11.

Christen WG, Glynn RJ, Chew EY, et al. Folic acid, pyridoxine, and cyanocobalamin combination treatment and age-related macular degeneration in women. Arch Intern Med. 2009;169:335-341.

Daroff. Bradley’s Neurology in Clinical Practice. 6th ed. Philadelphia, PA: Elsevier Saunders; 2012.

Friso S, Jacques PF, Wilson PW, Rosenberg IH, Selhub J. Low circulating vitamin B(6) is associated with elevation of the inflammation marker C-reactive protein independently of plasma homocysteine levels. Circulation. 2001;103(23):2788-2791.

Galluzzi L, Vacchelli E, Michels J, et al. Effects of vitamin B6 metabolism on oncogenesis, tumor progression and therapeutic responses. Oncogene. 2013;32(42):4995-5004.

Hines Burnham, et al, eds. Drug Facts and Comparisons. St. Louis, MO: Facts and Comparisons; 2000:18.

Jewell D, Young G. Interventions for nausea and vomiting in early pregnancy (Cochrane Review). Cochrane Database Syst Rev. 2002;(1):CD000145.

Kliegman. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: Elsevier Saunders; 2011.

Koren G, Maltepe C. Preventing recurrence of severe morning sickness. Can Fam Physician. 2006 Dec;52(12):1545-1546.

McNutty H, Pentieva K, Hoey L, Ward M. Homocysteine, B-vitamins and CVD. Proct Nutr Soc. 2008;67(2):232-237.

Morselli B, Neuenschwander B, Perrelet R, Lippunter K. Osteoporosis diet . Ther Umsch. 2000;57(3):152-160.

National Academy of Sciences. Dietary Reference Intakes (DRIs): Recommended Intakes for Individuals, Vitamins. Accessed June 1, 2011.

Ryan-Harshman M, Aldoori W. Carpal tunnel syndrome and vitamin B6. Can Fam Physician. 2007;53(7):1161-1162.

Schnyder G. Decreased rate of coronary restenosis after lowering of plasma homocysteine levels. N Eng J Med. 2001;345(22):1593-1600.

Ulvik A, Midttun O, Pedersen ER, Nygard O, Ueland PM. Association of plasma B-6 vitamers with systemic markers of inflammation before and after pyridoxine treatment in patients with stable angina pectoris. Am J Clin Nutr. 2012;95(5):1072-1078.

Vermeulen EGJ, Stehouwer CDA, Twisk JWR, et al. Effect of homocysteine-lowering treatment with folic acid plus vitamin B6 on progression of subclinical atherosclerosis: a randomised, placebo-controlled trial. Lancet. 2000;355:517-522.

Woolf K, Manore MM. Elevated plasma homocysteine and low vitamin B-6 status in nonsupplementing older women with rheumatoid arthritis. J Am Diet Assoc. 2008;108(3):443-453.

Review Date: 8/5/2015
Reviewed By: Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only — they do not constitute endorsements of those other sites. © 1997- A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

Pyridoxine, or vitamin B6, is one of eight B vitamins.

It helps the body convert food into fuel, metabolize fats and proteins, maintain proper functioning of nerves, and produce red blood cells.

Vitamin B6 is found in many foods, is added to foods, and is available as a dietary supplement.

The vitamin is used to treat and prevent a vitamin B6 deficiency, which can result from certain medicines, medical conditions, or a poor diet.

The recommended daily allowance (RDA) for vitamin B6 depends on your age and sex.

It ranges from 0.1 milligram (mg) for 6-month-old infants, 1.5 mg for women over 50, and 1.7 mg for men over 50.

During pregnancy, the recommended RDA is 1.9 mg, and 2.0 mg during lactation.

Vitamin B6 is water-soluble, which means the body doesn’t store it.

Vitamin B6 Deficiency

A serious vitamin B6 deficiency is relatively uncommon in the United States, but it is more likely in children and the elderly.

People with certain conditions also have a higher risk of vitamin B6 deficiency, including those who have:

  • Alcohol dependence
  • Kidney disease
  • Autoimmune disease
  • Celiac disease
  • Hyperthyroidism

Some medications may lead to vitamin B6 deficiency as well, including:

  • Pyridoxine-inactivating drugs (such as anticonvulsants)
  • Certain antibiotics (such as isoniazid and cycloserine for tuberculosis)
  • Hydralazine (Apresoline), a vasodilator that expands blood vessels and lowers blood pressure
  • Corticosteroids, used to treat autoimmune conditions (such as rheumatoid arthritis), allergies, and asthma
  • Penicillamine, a chelating agent used to remove copper and other substances from the body, and sometimes for severe rheumatoid arthritis

Symptoms of a serious deficiency can include nervousness, irritability, weakness, depression, difficulty concentrating, and short-term memory loss.

Other Uses for Vitamin B6

While vitamin B6 is typically taken to treat a deficiency, it’s also used for other purposes.

Some early research and anecdotal reports have shown the vitamin may play a role in:

  • Treating nausea and vomiting during pregnancy
  • Lowering heart disease risks
  • Treating seizures in infants
  • Preventing age-related macular degeneration
  • Reducing symptoms of depression
  • Treating a certain type of anemia
  • Improving premenstrual syndrome (PMS) symptoms
  • Treating carpal tunnel symptoms
  • Preventing kidney stones
  • Helping behavioral disorders in kids
  • Preventing certain types of cancer
  • Treating acne or other skin conditions
  • Improving memory and cognitive function in older adults
  • Treating rheumatoid arthritis
  • Improving symptoms of tardive dyskinesia (a movement disorder)

However, much more research is needed to confirm whether vitamin B6 can treat or prevent these conditions.

Vitamin B6 Foods

Many foods are good sources of vitamin B6. Some of these include:

  • Chicken
  • Turkey
  • Tuna
  • Shrimp
  • Salmon
  • Beef liver
  • Milk
  • Cheese
  • Lentils
  • Beans
  • Bananas
  • Spinach
  • Carrots
  • Brown rice
  • Sunflower seeds
  • Bran
  • Wheat germ
  • Whole-grain flour

Vitamin B6 Warnings

You shouldn’t take a dose above 100 milligrams (mg) a day without talking to your healthcare provider.

Very large doses of vitamin B6 can cause nerve damage or other neurological disorders.

Although rare, there have been some reports of allergic skin reactions to high doses of vitamin B6 supplements.

Always talk to your doctor before taking a supplement such as vitamin B6. Talk to a pediatrician before giving your child this vitamin.

Pregnancy and Vitamin B6

Vitamin B6 is a pregnancy category A drug, which means it’s not likely to harm an unborn baby.

However, you should tell your doctor if you are pregnant or plan to become pregnant while taking this supplement.

The vitamin can also be used while breastfeeding, but you should talk to your doctor first. You shouldn’t take high doses of vitamin B6 during pregnancy or while breastfeeding.


Vitamin B6 comprises six compounds – pyridoxal, pyridoxine, pyridoxamine and their respective 5′ phosphates (see table below). It acts as a coenzyme in the metabolism of amino acids, glycogen and sphingoid bases. The most common form in human tissue is the 5′-phosphate form of pyridoxal (PLP) most of which is found in muscle bound to phosphorylase. The second most common is the 5′-phosphate form of pyridoxamine (PMP). Plant foods contain primarily pyridoxine (PN) and its 5′-phosphate (PNP), sometimes in the form of a glucoside.

Absorption in the gut involves phosphatase-mediated hydrolysis and transport of the non-phosphorylated form to the mucosal cells. Quite large doses of PLP and PMP are well absorbed (Hamm et al 1979). PN glucoside is less well absorbed. Most of the absorbed non-phosphorylated vitamin B6 goes to the liver where conversion to the phosphorylated form occurs. The major excretory product is 4-pyridoxic acid that accounts for about half the B6 compounds in urine (Shultz & Leklem 1981).

Forms and equivalence of Vitamin B6 compounds

Vitamin B6 is found in a wide range of foods including organ meats, muscle meats, breakfast cereals, vegetables and fruits. Bioavailability is generally in the region of 75% in a mixed diet (Tarr et al 1981). It has been proposed that vitamin B6 requirements may be increased at higher protein intake (Baker et al 1964, Hansen et al 1996a, Linkswiler 1978), although other studies have not shown this (Pannemans et al 1994). Nevertheless, protein intake is generally taken into consideration in setting requirements for vitamin B6.

Clinical deficiency is rare. The symptoms of deficiency include seborrhaeic dermatitis (Mueller & Vilter 1950), microcytic anaemia (Snyderman et al 1953), convulsions (Bessey et al 1957, Coursin 1954) and depression and confusion (Hawkins & Barsky 1948).

Indicators used to assess requirements have ranged from measures of vitamin concentrations in plasma, blood cell or urine to functional measures such as erythrocyte aminotransferase saturation by pyridoxal 5′-phosphate or tryptophan metabolites. Most of these indicators change with dietary intake, but there is little information about what level would indicate a deficiency state. A review (Lui et al 1985) suggested that plasma PLP is probably the best single indicator as it reflects tissue stores.

Recommendations by life stage and gender


Age AI
0-6 months 0.1 mg/day
7-12 months 0.3 mg/day

Rationale: The AI for 0-6 months is calculated by multiplying the average intake of breast milk (0.78 L/day) by the average concentration of vitamin B6 present in human milk (0.13 mg/L) based on the studies of West & Kirksey (1976). For 7-12 months, the AI was extrapolated from that of the younger infants using a metabolic weight ratio (FNB:IOM 1998).

Children & adolescents

Rationale: As there are few data on children and adolescents, the EARs were set based on the adult EARs adjusted for metabolic body weight and growth (FNB:IOM 1998). In the absence of information on the standard deviation of requirement, the RDI was set assuming a CV of 10% for the EAR.


Rationale: Clinical deficiency is rarely seen at intakes below 0.5 mg/day, but various depletion-repletion studies suggest an average daily requirement of 1.1 mg/day in younger men for maintenance of tissue stores, although the range of study results was quite wide (Baker et al 1964, FNB:IOM 1998, Linkswiler 1978, Miller & Linkswiler 1967, Miller et al 1985, Selhub et al 1993, Yess et al 1964). For younger women, the average requirement seems to be similar (Brown et al 1975, FNB:IOM 1998, Hansen et al 1996a,b, 1997, Huang et al 1998, Kretsch et al 1995). The EAR appears to be higher for older people (Madigan et al 1998) and men have higher requirements than women. The increase due to age and gender appears to be about 0.2 to 0.3 mg of food vitamin B6 per day. RDIs for all groups were set assuming a CV of 10% for the EAR.


14-18 yr 1.6 mg/day 1.9 mg/day
19-30 yr 1.6 mg/day 1.9 mg/day
31-50 yr 1.6 mg/day 1.9 mg/day

Rationale: The EAR in pregnancy was based on additional requirements shown by studies of changes in plasma concentrations in pregnancy, foetal sequestration data and supplemental studies (Cleary et al 1975, Hamfelt & Tuvemo 1972, Contractor & Shane 1970, Shane & Contractor 1980, Lumeng et al 1976) that suggested that an additional allowance of 0.5 mg/day was justifiable. Because of the approximation of this figure, the adolescent EAR was set at the same level as that for older women. The RDI was set assuming a CV of 10% for the EAR.


14-18 yr 1.7 mg/day 2.0 mg/day
19-30 yr 1.7 mg/day 2.0 mg/day
31-50 yr 1.7 mg/day 2.0 mg/day

Rationale: The vitamin B6 in breast milk varies according to maternal vitamin B6 levels. The amount of vitamin B6 required to increase breast milk by a small increment is much higher than that increment. Accordingly, the additional requirement in lactation is higher than that suggested by the amount secreted in milk (Borschel et al 1986, West & Kirksey 1976). To ensure a breast milk vitamin B6 concentration of 0.13 mg/L, five times that amount must be consumed in addition to the EAR of 1.1 mg for non-lactating women. Because of the approximation of the estimate, the adolescent EAR was set as for older women. The RDI is set assuming a CV of 10% for the EAR.

Upper Level of Intake

Vitamin B6 as pyridoxine.

Age UL
0-12 months Not possible to establish; source of intake should be breast milk, formula or food only
Children and adolescents
1-3 yr 15 mg/day
4-8 yr 20 mg/day
9-13 yr 30 mg/day
14-18 yr 40 mg/day
Adults 19+ yr
Men 50 mg/day
Women 50 mg/day
14-18 yr 40 mg/day
19-50 yr 50 mg/day
14-18 yr 40 mg/day
19-50 yr 50 mg/day

Rationale: The ULs were set using results of studies involving long-term oral administration of pyridoxine at doses of less than 1g/day (Berger & Schaumburg 1984, Bernstein & Lobitz 1988, Dalton 1985, Dalton & Dalton 1987, Del Tredici et al 1985, FNB:IOM 1998, Parry & Bredesen 1985). A NOAEL of 200 mg/day was identified from the studies of Bernstein & Lobitz (1988) and Del Tredici et al (1985). These studies involved subjects who had generally been on the supplements for 5 to 6 months or less. The study of Dalton and Dalton (1987), however, suggested that symptoms might take substantially longer than this to appear. In this latter retrospective survey, subjects who reported symptoms had been on supplements for 2.9 years on average. Those reporting no symptoms had taken supplements for 1.9 years. Symptoms disappeared 6 months after cessation of supplements. Given these findings, a UF of 4 was used to derive the UL based on the limitations of the data involving pyridoxine doses of less than 500 mg/day (Berger & Schaumburg 1984, Parry & Bredesen 1985, Dalton 1985, Dalton & Dalton 1987, FNB:IOM 1998) and the limited duration of the studies. The UL for adults was thus set at 50 mg/day. The same figure was set for pregnancy and lactation as there is no evidence of teratogenicity at this level. The UL was set based on metabolic body size and growth considerations for all other ages and life stages except infancy. It was not possible to set a UL for infants, so intake is recommended in the form of food, milk or formula.

Baker EM, Canham JE, Nunes WT, Sauberlich HE, McDowell ME. Vitamin B6 requirement for adult men. Am J Clin Nutr 1964;15:59-66.

Berger A, Schaumburg HH. More on neuropathy from pyridoxyl abuse. N Engl J Med 1984;311:986-7.

Bernstein A, Lobitz CS. A clinical and electrophysiologic study of the treatment of painful diabetic neuropathies with pyridoxine. In: Leklem JE, Reynolds RD, eds. Clinical and physiological applications of vitamin B6. Current topics in nutrition and disease. New York: Alan R. Liss, 1988. Pp 415-23.

Bessey OA, Adam DJ, Hansen AE. Intake of vitamin B6 and infantile convulsions: a first approximation of requirements of pyridoxine in infants. Paediatrics 1957;20:33-44.

Borschel MW, Kirksey A, Hanneman RE. Effects of vitamin B6 intake on nutriture and growth of young infants. Am J Clin Nutr 1986;43:7-15.

Brown RR, Rose DP, Leklem JE, Linkswiler H, Arand R. Urinary 4-pyridoxic acid, plasma pyridoxyl phosphate and erythrocyte aminotransferase levels in oral contraceptive users receiving controlled intakes of vitamin B6. Am J Clin Nutr 1975;28:10-9.

Cleary RE, Lumeng L, Li TK. Maternal and fetal plasma levels of pyridoxal phosphate at term: adequacy of vitamin B6 supplementation during pregnancy. Am J Obstet Gynecol 1975;121:25-8.

Contractor SF, Shane B. Blood and urine levels of vitamin B6 in the mother and fetus before and after loading of the mother with vitamin B6. Am J Obstet Gynecol 1970;107:635-40.

Coursin DB. Convulsive seizures in infants with pyridoxine-deficient diet. JAMA 1954;154:406-8.

Dalton K. Pyridoxine overdose in premenstrual syndrome. Lancet 1985;i:1168-9

Dalton K, Dalton MJT. Characteristics of pyridoxine overdose neuropathy syndrome. Acta Neurol Scand 1987;76:8-11

Del Tredici AM, Bernstein AL, Chinn K. Carpel tunnel syndrome and vitamin B6 therapy. In: Reynolds RD, Leklem JD, eds. Vitamin B6: its role in health and disease. Current topics in nutrition and disease. New York: Alan R. Liss,1985. Pp 459-62.

Food and Nutrition Board: Institute of Medicine (FNB:IOM). Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic acid, Biotin and Choline. Washington, DC: National Academy Press,1998.

Hamfelt A, Tuvemo T. Pyridoxyl phosphate and folic acid concentration in blood and erythrocyte aspartate aminotransferase activity during pregnancy. Clin Chim Acta 1972;41:287-98.

Hamm MW, Mehansho H, Henderson LM. Transport and metabolism of pyridoxamine and pyridoxamine phosphate in the small intestine of the rat. J Nutr 1979;109:1552-9.

Hansen CM, Leklem JE, Miller LT. Vitamin B6 status of women with a constant intake of vitamin B6 changes with three levels of dietary protein. J Nutr 1996a;126:1891-901.

Hansen CM, Leklem JE, Miller LT. Vitamin B6 status indicators decrease in women consuming a diet high in pyridoxine glucoside. J Nutr 1996b;126:2512-8.

Hansen CM, Leklem JE, Miller LT. Changes in vitamin B6 status indicators of women fed a constant protein diet with varying levels of vitamin B6. Am J Clin Nutr 1997;66:

Hawkins WW, Barsky J. An experiment on human vitamin B6 deprivation. Science, 1948;108:284-6.

Huang Y-C, Chen W, Evans MA, Mitchell ME, Shultz TD. Vitamin B6 requirement and status assessment of young women fed a high-protein diet with various levels of vitamin B6. Am J Clin Nutr 1998;67:208-20.

Kretsch MJ, Sauberlich HE, Skala JH, Johnson Hl. Vitamin B6 requirement and status assessment: young women fed a depletion diet followed by a plant-or animal-protein diet with graded amounts of vitamin B6. Am J Clin Nutr 1995;61:1091-101.

Linkswiler HM. Vitamin B6 requirements of men. In: Human vitamin B6 requirements: proceedings of a workshop. Washington, DC: National Academy of Sciences, 1978. Pp 279-90.

Lui A, Lumeng L, Aronoff GR, Li T-K. Effect of oral contraceptives on the plasma concentration of pyridoxyl phosphate. Am J Clin Nutr 1985;27:326-33.

Lumeng L, Clearey RE, Wagner R, Pao-Lo Y, Li TK. Adequacy of vitamin B6 supplementation during pregnancy: a prospective study. Am J Clin Nutr 1976;29:

Madigan SM, Tracey F, McNulty H, Eaton-Evans J, Coulter J, McCartney H, Strain JJ. Riboflavin and vitamin B-6 intakes and status, and biochemical response to riboflavin supplementation, in free-living elderly people. Am J Clin Nutr 1998;68:389-95.

Miller LT, Leklem JE, Shulktz TD. The effect of dietary protein on the metabolism of vitamin B6 in humans. J Nutr 1985;115:1663-72.

Miller LT, Linkswiler H. Effect of protein intake on the development of abnormal tryptophan metabolism by men during vitamin B6 depletion. J Nutr 1967;93:53-9.

Mueller JF, Vilter RW. Pyridoxine deficiency in human beings being induced by desoxypyridoxine. J Clin Invest 1950;29:193-201.

Pannemans DL, van den Berg H, Westerterp KR. The influence of protein intake on vitamin B-6 metabolism differs in young and elderly humans. J Nutr 1994;124:1207-14.

Parry GJ, Bredesen DE. Sensory neuropathy with low-dose pyridoxine. Neurology 1985;35:1466-8.

Selhub J, Jacques PF, Wilson PWF, Rush D, Rosenberg H. Vitamin status and intake as primary determinants of homocysteinemia in an elderly population. JAMA 1993;270:2693-8.

Shane B, Contractor SF. Vitamin B6 status and metabolism in pregnancy. In: Tryfiates GP, ed. Vitamin B6 metabolism and role in growth. Westport, CT: Food & Nutrition Press, 1980. Pp 137-71.

Shultz TD, Leklem JE. Urinary 4-pyridoxic acid, urinary vitamin B6 status and dietary intake in adults. In: Leklem JE, Reynolds RD, eds. Methods in vitamin B6 nutrition. New York: Plenum Press, 1981.Pp 250-65.

Snyderman SE, Holt LE, Carretero R, Jacobs K. Pyridoxine deficiency in the human infant. Am J Clin Nutr 1953;1:200.

Tarr JB, Tamura T, Stokstad EL. Availability of vitamin B6 and pantothenate in an average American diet in man. Am J Clin Nutr 1981;62:802-8.

West KD, Kirksey A. Influence of vitamin B6 intake on the content of the vitamin in human milk. Am J Clin Nutr 1976;29:961-9.

Yess N. Price J, Brown RR, Swan PB, Linkswiler H. Vitamin B6 depletion in man: urinary excretion of tryptophan metabolites. J Nutr 1964;84:229-36.

CFR – Code of Federal Regulations Title 21

(b) The ingredient meets the specifications of the Food Chemicals Codex, 3d Ed. (1981), p. 260, which is incorporated by reference. Copies are available from the National Academy Press, 2101 Constitution Ave. NW., Washington, DC 20418, or available for inspection at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federalregister/codeoffederalregulations/ibrlocations.html.

(c) In accordance with 184.1(b)(1), the ingredient is used in food with no limitation other than current good manufacturing practice. The affirmation of this ingredient as generally recognized as safe (GRAS) as a direct human food ingredient is based upon the following current good manufacturing practice conditions of use:

(1) The ingredient is used as a nutrient supplement as defined in 170.3(o)(20) of this chapter.

(2) The ingredient is used in the following foods at levels not to exceed current good manufacturing practice: baked goods as defined in 170.3(n)(1) of this chapter; nonalcoholic beverages and beverage bases as defined in 170.3(n)(3) of this chapter; breakfast cereals as defined in 170.3(n)(4) of this chapter; dairy product analogs as defined in 170.3(n)(10) of this chapter; meat products as defined in 170.3(n)(29) of this chapter; milk products as defined in 170.3(n)(31) of this chapter; plant protein products as defined in 170.3(n)(33) of this chapter; and snack foods as defined in 170.3(n)(37) of this chapter. Pyridoxine hydrochloride may be used in infant formula in accordance with section 412(g) of the Federal Food, Drug, and Cosmetic Act (the Act) or with regulations promulgated under section 412(a)(2) of the Act.

(d) Prior sanctions for this ingredient different from the uses established in this section do not exist or have been waived.

Why do we need magnesium?

Share on PinterestMany types of nuts and seeds are rich in magnesium.

Magnesium is one of seven essential macrominerals. These macrominerals are minerals that people need to consume in relatively large amounts — at least 100 milligrams (mg) per day. Microminerals, such as iron and zinc, are just as important, though people need them in smaller amounts.

Magnesium is vital for many bodily functions. Getting enough of this mineral can help prevent or treat chronic diseases, including Alzheimer’s disease, type 2 diabetes, cardiovascular disease, and migraine.

The following sections discuss the function of magnesium in the body and its effects on a person’s health.

1. Bone health

While most research has focused on the role of calcium in bone health, magnesium is also essential for healthy bone formation.

Research from 2013 has linked adequate magnesium intake with higher bone density, improved bone crystal formation, and a lower risk of osteoporosis in females after menopause.

Magnesium may improve bone health both directly and indirectly, as it helps to regulate calcium and vitamin D levels, which are two other nutrients vital for bone health.

2. Diabetes

Research has linked high magnesium diets with a lower risk of type 2 diabetes. This may be because magnesium plays an important role in glucose control and insulin metabolism.

A 2015 review in the World Journal of Diabetes reports that most, but not all, people with diabetes have low magnesium and that magnesium may play a role in diabetes management.

A magnesium deficiency may worsen insulin resistance, which is a condition that often develops before type 2 diabetes. On the other hand, insulin resistance may cause low magnesium levels.

In many studies, researchers have linked high magnesium diets with diabetes. In addition, a systematic review from 2017 suggests that taking magnesium supplements can also improve insulin sensitivity in people with low magnesium levels.

However, researchers need to gather more evidence before doctors can routinely use magnesium for glycemic control in people with diabetes.

3. Cardiovascular health

The body needs magnesium to maintain the health of muscles, including the heart. Research has found that magnesium plays an important role in heart health.

A 2018 review reports that magnesium deficiency can increase a person’s risk of cardiovascular problems. This is partly due to its roles on a cellular level. The authors observe that magnesium deficiency is common in people with congestive heart failure and can worsen their clinical outcomes.

People who receive magnesium soon after a heart attack have a lower risk of mortality. Doctors sometimes use magnesium during treatment for congestive heart failure (CHF) to reduce the risk of arrhythmia, or abnormal heart rhythm.

According to a 2019 meta-analysis, increasing magnesium intake may lower a person’s risk of stroke. They report that for each 100 mg per day increase in magnesium, the risk of stroke reduced by 2%.

Some research also suggests that magnesium plays a role in hypertension. However, according to the Office of Dietary Supplements (ODS), based on current research, taking magnesium supplements lowers blood pressure “to only a small extent.”

The ODS call for a “large, well-designed” investigation to understand the role of magnesium in heart health and the prevention of cardiovascular disease.

4. Migraine headaches

Magnesium therapy may help prevent or relieve headaches. This is because a magnesium deficiency can affect neurotransmitters and restrict blood vessel constriction, which are factors doctors link to migraine.

People who experience migraines may have lower levels of magnesium in their blood and body tissues compared with others. Magnesium levels in a person’s brain may be low during a migraine.

A systematic review from 2017 states that magnesium therapy may be useful for preventing migraine. The authors suggest that taking 600 mg of magnesium citrate appears to be a safe and effective prevention strategy.

The American Migraine Foundation report that people frequently use doses of 400–500 mg per day for migraine prevention.

The amounts that may have an affect are likely to be high, and people should only use this therapy under the guidance of their doctor.

Read more about magnesium for migraine.

5. Premenstrual syndrome

Magnesium may also play a role in premenstrual syndrome (PMS).

Small-scale studies, including a 2012 article, suggest that taking magnesium supplements along with vitamin B-6 can improve PMS symptoms. However, a more recent 2019 review reports that the research is mixed, and further studies are needed.

The American College of Obstetricians and Gynecologists suggest that taking magnesium supplements could help to reduce bloating, mood symptoms, and breast tenderness in PMS.

6. Anxiety

Magnesium levels may play a role in mood disorders, including depression and anxiety.

According to a systematic review from 2017, low magnesium levels may have links with higher levels of anxiety. This is partly due to activity in the hypothalamic-pituitary-adrenal (HPA) axis, which is a set of three glands that control a person’s reaction to stress.

However, the review points out that the quality of evidence is poor, and that researchers need to do high quality studies to find out how well magnesium supplements might work for reducing anxiety.

From October 1st, 2018, dietary supplements may not contain a daily dose of more than 21 milligram vitamin B6 in the Netherlands. A higher vitamin B6 intake can have a harmful effect on health.

High doses of vitamin B6 are associated with neuropathy. The Netherlands Pharmacovigilance Centre Lareb received over 100 reports of neuropathy related complaints after use of freely available dietary supplements containing vitamin B6. These reports have been sent to the Dutch Food and Consumer Product Safety Authority, who is responsible for the regulation of these products, with the recommendation to regulate the maximum daily dose of vitamin B6 in supplements that they regulate.

Based on the risk assessment, the Dutch Food and Consumer Product Safety Authority advised the minister of Public Health, Welfare and Sport to establish a national maximum daily dose for vitamin B6 in freely available dietary supplements. The minister adopted this advice.

From October 1st, 2018, the maximum daily dose of vitamin B6 in dietary supplements may not exceed 21 milligram. This maximum daily dose is based on the maximum safe upper limit for vitamin B6, taken into account that part of vitamin B6 intake comes from food. The maximum safe upper limit for vitamin B6 is lower for children compared to adults. For this reason, the maximum daily dose of vitamin B6 in dietary supplements for children is also lower:

Dosing vitamin B6 in supplements and warning on label:

  • Until 3 milligrams/day, with warning ‘not suitable for children under 1 year of age’
  • 3 milligrams/day and more, with warning ‘not suitable for children under 4 years of age’
  • 5 milligrams/day and more, with warning ‘not suitable for children under 11 years of age’
  • 7 milligrams/day and more, with warning ‘not suitable for children under 18 years of age’

What is the maximum dosage of B vitamins?

The B vitamins include B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (Pantothenic acid), B6 (pyridoxamine), B7 (biotin) B9 (folic acid), and B12. They are together or separately involved in most of the body’s metabolic processes. The maximum dosage is often scientifically referred to as The Tolerable Upper Intake Level (UL) or the highest level of daily nutrient intake that is likely to pose no risk of adverse health effects most healthy individuals. Intake above the UL increases risk of adverse events. There are not many ULs set for B vitamins because they are water soluble, meaning the body excretes most of what it doesn’t use making overdoing on B vitamins difficult but possible with some. Below is what is known about the maximum dose of some of the B vitamins.

  • Thiamin: There are no reports available of adverse effects from consumption of excess thiamin by ingestion of food and supplements. Because the data are inadequate for a quantitative risk assessment, no Tolerable Upper Intake Level (UL) can be derived for thiamin but stay below 25mgs unless advised by a doctor.
  • Riboflavin: No adverse effects were reported in humans after single oral doses of up to 60 mg of supplemental riboflavin and there is no UL at this time.
  • Niacin: Although the UL is set at 35mgs because niacin can cause harmless flushing, niacin in the form of niacinamide can be taken in far larger doses but stay below 100mgs.
  • Vitamin B6 (Pyridoxine): 100mgs/day is the UL but stay below 50mgs unless advised by a qualified physician
  • Folate: the UL for adults is 1 mg/day or 1,000 µg/day
  • Vitamin B12: No adverse effects have been associated with excess B12 intake from food or supplements in healthy individuals.
  • Pantothenic acid: No reports of adverse effects of oral pantothenic acid in humans or animals were found and therefore no UL has been set.

The goal is to make sure you get proper daily amounts of all necessary B vitamins. This goal is accomplished by eating a healthy diet (as found in the Sharecare Fitness application) and taking a daily multivitamin and mineral formula that contains the necessary B vitamins within the amounts shown below (upper portion of range for active people and/or dieters unless otherwise noted):

About the author

Leave a Reply

Your email address will not be published. Required fields are marked *