Vitamin B refers to not one, but eight different vitamins. All B vitamins play a role in converting food into energy in the body. Each vitamin also has a unique role in a person’s health. Benefits and uses of B-complex vitamins.
Vitamin B-complex supplements include all of the essential B vitamins in one pill. Some contain 100 percent of the recommended daily allowance (RDA) of every B vitamin. Others contain higher doses of some or all of these vitamins.
Many people get all the vitamin B they need from a varied, healthful diet, but others benefit from taking a vitamin B-complex supplement.
Vitamin B-1 – thiamin
Vitamin B-1 is vital to the healthy growth and function of organs, including the brain and heart.
Vitamin B-2 – riboflavin
The body needs vitamin B-2 to break down fats and drugs.
Vitamin B-3 – niacin
The body needs niacin to maintain healthy skin, nerves, and digestion. Doctors sometimes prescribe high doses of niacin to help improve cholesterol levels.
Vitamin B-5 – pantothenic acid
Vitamin B-5 is essential for the health of the brain and nervous system.
Vitamin B-6 – pyridoxine
Vitamin B-6 helps the body make new red blood cells, which carry oxygen throughout the body. It also helps keep the immune system strong.
Vitamin B-7 – biotin
Biotin is essential for healthy hair, nails, and nerve function.
Vitamin B-9 – folic acid
The body uses folic acid — or folate, its natural form — to make DNA and genetic material. During pregnancy, folic acid may reduce the risk of certain birth defects.
Vitamin B-12 – cobalamin
The body’s nerve and blood cells require vitamin B-12. Adequate levels of B-12 also prevent pernicious anemia, which is a deficiency of this nutrient.
Many B-complex supplements contain about 100 percent of the RDA of each of the eight B vitamins.
However, some contain very high levels of certain B vitamins. Before taking a high-dose supplement, talk with a clinician.
The following are RDAs for each of the B vitamins, in milligrams (mg) or micrograms (mcg), according to The National Institutes of Health Office of Dietary Supplements. Older adults may require higher dosages of some B vitamins.
|Males||Females||During pregnancy||During breastfeeding|
|Vitamin B-1||1.2 mg||1.1 mg||1.4 mg||1.4 mg|
|Vitamin B-2||1.3 mg||1.1 mg||1.4 mg||1.6 mg|
|Vitamin B-3 or dietary equivalents||16 mg||14 mg||18 mg||17 mg|
|Vitamin B-5||5 mg||5 mg||6 mg||7 mg|
|Vitamin B-6||1.3 mg||1.5 mg||1.9 mg||2.0 mg|
|Vitamin B-7||30 mcg||30 mcg||30 mcg||35 mcg|
|Vitamin B-9 or dietary equivalents||400 mcg||400 mcg||600 mcg||500 mcg|
|Vitamin B-12||2.4 mcg||2.4 mcg||2.6 mcg||2.8 mcg|
Benefits and uses
Vitamin B-complex supplements may help with certain health problems. If a person has any of the conditions listed below, they may benefit from taking a supplement that contains B vitamins:
Some research suggests that certain B vitamins could help prevent migraine with aura, specifically:
- vitamin B-6
- vitamin B-9
- vitamin B-12
The researchers also suggest that vitamin B-2 could help prevent migraine by influencing mitochondrial dysfunction, which occurs at the cellular level.
Authors of a review study from 2017 looked at the effects of vitamin B-2 on migraine. They report that this vitamin is well-tolerated and effective at reducing migraine frequency in adults, though they recommend further research.
Depression and anxiety
Authors of a study from 2018 state that vitamin B-12 levels play an important role in the development and presentation of depression and anxiety. They report that participants with depression or anxiety had lower levels of B-12 than their control counterparts.
A meta-analysis found that B vitamins could help with depression in certain cases. The researchers said that taking some B vitamins regularly for several weeks to years could reduce the risk of depression relapse.
A small-scale study in India also suggested that B-9 and B-12 deficiencies play a role in depression and anxiety.
B vitamins may help the skin heal.
One study found that, when applied to the skin, these vitamins helped wounds heal more effectively. Another study found that B-12 improved wound healing in mice with diabetes.
Vitamin B-12 may be helpful in treating canker sores, also known as oral ulcers. A double-blind study found that a B-12 ointment relieved pain better than a placebo.
Premenstrual syndrome (PMS).
Some evidence suggests that taking a combined supplement of B-6 and calcium improves symptoms of premenstrual syndrome (PMS).
A systematic review and meta-analysis also found vitamin B-6 to be helpful in controlling physical and psychological PMS symptoms.