Vitamin B Complex: Hormone Regulation + Optimal Health

You are here:

Table of Contents

Vitamin B complex is a multivitamin that packs the benefits of several B vitamins into one convenient dietary supplement. There are eight B vitamins, each with their own unique health benefits.

Vitamin B complex supplements, which combine all the essential B vitamins into a single dose, are often available in capsule or tablet form. This convenient way to simultaneously intake all the B vitamins may benefit your heart, sleep, mind, and more.

Health Benefits of Vitamin B Complex

There are eight B vitamins, each with unique functions and benefits. Often, though, supplements combine several B vitamins into one multivitamin, also called a vitamin B complex.

Below, I’ve listed the most common, evidence-based health benefits of a vitamin B complex:

B Vitamin Food Sources & Functions

Below are the eight B vitamins, their primary functions, and good sources of each. Remember that many cereals, breads, and dairy products are fortified with various B vitamins, although this isn’t necessarily an ideal way to get more B vitamins.

VitaminFunctionsFood Sources
Thiamin (Vitamin B1)Energy metabolism, nervous system functionNuts, peas, organ meats, whole grains
Riboflavin (Vitamin B2)Energy production, skin healthMilk, eggs, mushrooms
Niacin (Vitamin B3)Metabolism, DNA repairFish, eggs, meat
Pantothenic acid (Vitamin B5)Hormone production, cholesterol synthesis, amino acid metabolismEggs, avocados, mushrooms, organ meats
Pyridoxine (Vitamin B6)Immune system function, brain development, enzyme cofactor, stress regulationMilk, poultry, oats, peanuts
Biotin (Vitamin B7)Healthy skin, hair, and nails, carbohydrate and fat metabolismOrgan meats, salmon, eggs, avocado
Folate (Vitamin B9)Amino acid metabolism, fetal development, prevention of birth defectsLeafy green vegetables, organ meats
Cobalamin (Vitamin B12)Red blood cell formation, nervous system function, prevention of birth defectsMilk, cheese, eggs, fish
Subscribe to our newsletter to stay informed on Health Topics like this!
Get primehealth updates right to your inbox

When to Consider Supplements

Getting all your essential vitamins through a variety of foods is ideal. However, most people don’t consume enough vitamins and minerals from food alone, and that’s where dietary supplements come in.

Taking supplements is a great way to get the essential nutrients to help your body thrive. If you have a clinical or subclinical deficiency, you might want to invest in supplements.

Consider taking a vitamin B complex if you are exhibiting these signs of vitamin B deficiency:

  • Fatigue
  • Sore mouth, tongue
  • Nausea, vomiting
  • Diarrhea
  • Memory problems
  • Unexplained weight loss

If you are experiencing yellow skin (jaundice), this may be a sign of anemia caused by severe vitamin B12 deficiency. In the case of jaundice, you should see a healthcare provider right away — don’t just self-diagnose and treat this with a vitamin B complex supplement.

I recommend that the following people take a B complex, regardless of deficiency symptoms:

  • Adults older than 65
  • Pregnant and breastfeeding people
  • Those on a strict vegan diet

Dosage and Side Effects

To get dosage information, carefully read manufacturer labels and talk to your doctor about a vitamin B dosage that fits your unique needs. You may need a functional healthcare professional to get the best supplement advice.

Potential side effects of vitamin B intake may include:

  • Flushing
  • Headache
  • Stomach discomfort

Taking very high doses puts you at a greater risk of experiencing one of these mild side effects. In rare cases, long-term overdose of vitamins B6 and B9 may lead to nerve damage, specifically peripheral neuropathy.

Certain medications may reduce your vitamin B absorption. These undesirable interactions may include:

  • Vitamin C (ascorbic acid) — to avoid this, take vitamin C at least 2 hours after taking a vitamin B complex
  • Proton pump inhibitors
  • Aminosalicylic acid (Paser)
  • Colchicine (Mitigare)
  • Metformin (Glumetza)


Is it OK to take vitamin B complex every day?

Yes, it’s ok to take vitamin B complex every day. Many recommended dosages suggest taking it twice a day.

You cannot “overdose” on B vitamins since they’re water-soluble vitamins — even though there may be mild side effects if you take too much.

Who should not take a B complex?

People who have the following health conditions should talk to their doctor before taking a B complex, whether due to potential complications or vitamin B malabsorption:

Do I need to take methylated B vitamins?

People with an MTHFR gene mutation may benefit from taking methylated B9 (folate) and B12. An MTHFR mutation can cause impaired processing of folate (vitamin B9) and B12 into the active forms of these nutrients. Those with this mutation should avoid the inactive form of folate or folic acid and take methylated folate and B12 instead.

Can a vitamin B complex help with anxiety?

Vitamin B complexes that contain vitamins B9 and B12 may help with anxiety, both directly and indirectly.

Folic acid (vitamin B9) and cobalamin (vitamin B12) deficiencies may cause anxiety and depression. Ensuring you have enough vitamin B9 and B12 helps prevent anxiety.

Read more: Can Hormones Cause Anxiety?


  1. Gonçalves, A. C., & Portari, G. V. (2021). The B-complex vitamins related to energy metabolism and their role in exercise performance: a narrative review. Science & Sports, 36(6), 433-440.
  2. Young, L. M., Pipingas, A., White, D. J., Gauci, S., & Scholey, A. (2019). A systematic review and meta-analysis of B vitamin supplementation on depressive symptoms, anxiety, and stress: Effects on healthy and ‘at-risk’individuals. Nutrients, 11(9), 2232.
  3. Miao, Y., Guo, Y., Chen, Y., Lin, Y., Lu, Y., & Guo, Q. (2023). The effect of B-vitamins on the prevention and treatment of cardiovascular diseases: a systematic review and meta-analysis. Nutrition Reviews, nuad127.
  4. Lee, M. C., Hsu, Y. J., Shen, S. Y., Ho, C. S., & Huang, C. C. (2023). A functional evaluation of anti-fatigue and exercise performance improvement following vitamin B complex supplementation in healthy humans, a randomized double-blind trial. International Journal of Medical Sciences, 20(10), 1272.
  5. Kennedy, D. O. (2016). B vitamins and the brain: mechanisms, dose and efficacy—a review. Nutrients, 8(2), 68.
  6. Krishnamurthy, H. K., Reddy, S., Jayaraman, V., Krishna, K., Song, Q., Rajasekaran, K. E., … & Rajasekaran, J. J. (2021). Effect of micronutrients on thyroid parameters. Journal of Thyroid Research, 2021, 1-8.
  7. Kim, K., Mills, J. L., Michels, K. A., Chaljub, E. N., Wactawski-Wende, J., Plowden, T. C., & Mumford, S. L. (2020). Dietary intakes of vitamin B-2 (riboflavin), vitamin B-6, and vitamin B-12 and ovarian cycle function among premenopausal women. Journal of the Academy of Nutrition and Dietetics, 120(5), 885-892.
  8. Camfield, D. A., Wetherell, M. A., Scholey, A. B., Cox, K. H., Fogg, E., White, D. J., … & Pipingas, A. (2013). The effects of multivitamin supplementation on diurnal cortisol secretion and perceived stress. Nutrients, 5(11), 4429-4450.
  9. Ali, M. A., Hafez, H. A., Kamel, M. A., Ghamry, H. I., Shukry, M., & Farag, M. A. (2022). Dietary Vitamin B Complex: Orchestration in Human Nutrition throughout Life with Sex Differences. Nutrients, 14(19), 3940.
  10. Ankar, A., & Kumar, A. (2022). Vitamin B12 deficiency. In StatPearls [Internet]. StatPearls Publishing.
  11. Hanna, M., Jaqua, E., Nguyen, V., & Clay, J. B. (2022). B Vitamins: Functions and Uses in Medicine. Perm. J, 26, 89-97.
  12. Esnafoglu, E., & Ozturan, D. D. (2020). The relationship of severity of depression with homocysteine, folate, vitamin B12, and vitamin D levels in children and adolescents.Child and adolescent mental health, 25(4), 249-255.
PrimeHealth Newsletter
Get tips & advice right to your inbox, plus stay up to date on PrimeHealth group visits and services.

Share this Post