Taking vitamins is usually good for your health, but is it possible to take too much?

The answer is yes.

You get all eight B vitamins when you take aB complex supplement.

A person taking a vitamin supplement capsule

Tetiana Melnyk / Getty Images

Side effects differ for each of the eight vitamins.

B1 (Thiamine)

Having excess levels ofthiaminedoesnt often occur since the body removes the excess through the urine.

However, extremely high amounts might cause an upset stomach.

At very high levels, it might turn urine a very bright yellow color.

B3 (Niacin)

Niacinmay be prescribed in higher doses for health conditions such as high cholesterol.

When taken in doses over 100 times the RDA, niacin can cause:

4.

This results in a feeling of numbness or tingling in the hands and feet.

Other side effects from too much B6 can include:

6.

Always let your healthcare provider know if youre taking biotin supplements before any blood tests.

B9 (Folate)

Taking too muchfolatecan hide a vitamin B12 deficiency, which might lead to nerve damage.

B12 (Cobalamin)

Vitamin B12is usually considered to be safe, and no upper limit has been determined.

Depending on the dosage, you may experience side effects from one or more specific vitamins other than B12.

For recommended doses with certain health conditions, such as during pregnancy, talk to a healthcare provider.

Who Should Avoid B Complex Supplements?

Do not take these supplements if you have an allergy to any of the ingredients.

Vitamin B complex includes eight essential B vitamins, each playing a vital role in the body.

To avoid side effects, stick to the recommended dosage unless directed by a healthcare provider.

If side effects occur, stop the supplement, stay hydrated, and consult a healthcare provider if needed.

2022;26(2):89. doi: 10.7812/TPP/21.204

MedlinePlus.Thiamine.

2024;16(18):3141. doi:10.33990/nu16183141

Office of Dietary Supplements.Niacin.

Office of Dietary Supplements.Pantothenic acid.

Paluszny A, Qiu S.Vitamin b6 toxicity secondary to daily multivitamin use: a case report.Cureus.

2023;15(11):e48792.

doi:10.7759/cureus.48792

Office of Dietary Supplements.Biotin.

Office of Dietary Supplements.Folate.

Office of Dietary Supplements.Vitamin B12.

Office of Dietary Supplements.Riboflavin.

Office of Dietary Supplements.Pyridoxine.

Kaiser Permanente.Vitamin B complex capsule.

USDA.Dietary guidelines for Americans.