What is it?

The B vitamins are a group of eight nutrients – B1 (thamin), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin), B9 (folic acid), and B12 (cobalamin). Each vitamin has unique roles in keeping the body health, while most of them are maintaining cell health and keeping you energized. We consume our B vitamins from food of different sources, while different kind of foods are rich with different types of vitamin B. Vitamin B12 is found in meat and dairy products, Vitamin B6 can be found in poultry, fish, and fruits, and B1 and 2 are in whole grains and eggs. B complex deficiency may caused by an abnormal, unbalanced diet, by alcoholism, by absorption disorders, or by other reasons including genetic reasons.

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Additional names

This group contains additional names:
- Biotin deficiency

Signs & symptoms

The symptoms of a vitamin B deficiency vary depending on which B vitamin is in shortage. Vitamin B12 deficiency – vitamin B12 helps regulate the nervous system, and a shortage of B12 can lead to disruption in the nervous system. This includes dementia, paranoia, depression, and behavioral changes. It may also cause constipation, weight loss, numbness, and balance problems. Vitamin B6 deficiency – the vitamin helps turn the food into energy and to fight infection, so a lack of vitamin B6 may cause depression, anemia, confusion, and susceptibility to infections. Vitamin B1 and 2 also help convert food into energy, while B2 helps maintain proper eyesight. The symptoms of lack of these vitamins usually include confusion and cracks along the sides of the mouth. Vitamin B3 aids in proper digestion, and cell development. The symptoms in a shortage of vitamin B3 may include rough skin, a bright red tongue, vomiting, changes in bowel movement, and hallucinations. Vitamin B9 fosters the growth of red blood cells, it also reduces the risk of birth defects when pregnant women consume it. The symptoms of vitamin B9 deficiency are megaloblastic anemia, fatigue, irritability, shortness of breath, open sores in mouth, and neural tube defects in newborn in case of a pregnant woman with vitamin B9 deficiency.


The diagnosis of vitamin B deficiency is made with a simple blood test modified to a specific vitamin B type, based on the patient's symptoms and habits.


The best treatment for vitamin B complex deficiencies is prevention. Keeping on a healthy, varied, and balanced diet should prevent most of the cases for B-complex deficiencies. People with special diets like vegetarian, vegan, and people with celiac disease should have their vitamin B complex as well as other vitamins checked on a regular basis. In case of a current shortage of vitamins, the treatment is a consumption of these vitamins, either by food, pills, fluid, or in acute cases intravenous.

☝️ This is not a substitute for professional medical advice. Please consult with your physician before making any medical decision.

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