What is vitamin B complex?

B complex vitamins are composed of eight B vitamins:

• B-1 (Thiamine)
• B-2 (riboflavin)
• B-3 (niacin)
• B-5 (pantothenic acid)
• B-6 (pyridoxine)
• B-7 (Biotin)
• B-9 (folic acid)
• B-12 (Cobalamin)

Each of these essential vitamins contributes to your overall body function. Read on to learn more about how these nutrients can benefit you, how much you need, whether you should take supplements, and more.

What are the benefits?

B vitamins play a vital role in maintaining good health and well-being. As the building blocks of a healthy body, B vitamins have a direct impact on your energy levels, brain function, and cell metabolism.

B complex vitamins help prevent infections and help support or promote:

• Cell Health
• Growth of red blood cells
• Energy Level
• Good eyesight
• Healthy brain function
• Good digestion
• Healthy Appetite
• Proper neurological function
• Production of hormones and cholesterol
• Cardiovascular health
• Muscle tone

Among women

B vitamins are especially important for pregnant and breastfeeding women. These vitamins help fetal brain development and reduce the risk of birth defects.

For expectant mothers, B vitamins can increase energy levels, relieve nausea, and reduce the risk of preeclampsia.

Among men

B vitamins are thought to increase testosterone levels in men, which naturally decrease with age. They can also help men build muscle and increase strength. However, human studies substantiating these claims are lacking.

The recommended daily amount of each B vitamin varies.

For women, the recommended daily intake is:

• B-1: 1.1 milligrams (mg)
• B-2: 1.1 mg
• B-3: 14 mg
• B-5: 5 mg
• B-6: 1.3 mg
• Biotin: 30 micrograms (mcg)
• Folic acid: 400 mcg
• B-12: 2.4 micrograms

For men, the recommended daily intake is:

• B-1: 1.2 mg
• B-2: 1.3 mg
• B-3: 16 mg
• B-5: 5 mg
• B-6: 1.3 mg
• Biotin: 30 mcg
• Folic acid: 400 mcg
• B-12: 2.4 micrograms

Older PeopleTrusted Source Pregnant women need more B vitamins. Your doctor can provide dosage information tailored to your individual needs.

Certain underlying health conditions can prevent your body from absorbing B vitamins properly. You should also discuss your B vitamin intake with your doctor if you:

• Celiac disease
• HIV
• Crohn's disease
• Alcohol dependence
• Kidney disease
• Rheumatoid arthritis
• Ulcerative colitis
• Inflammatory bowel disease

How do you know if you are deficient?

Most people get enough B vitamins through a balanced diet. However, deficiencies may still occur.

The following symptoms may indicate that you are not getting enough B vitamins:

• Skin rash
• Cracks around the mouth
• Scaly skin on lips
• Swollen tongue
• Fatigue
• Weaknesses
• Anemia
• Confusion
• Irritability or depression
• Disgusting
• Abdominal cramps
• Diarrhea
• Constipation
• Numbness or tingling in feet and hands

If you experience any of these symptoms and are unsure of the cause, make an appointment to see your doctor.

While you may be deficient in vitamin B, these symptoms also overlap with many other underlying conditions. Your doctor can make a diagnosis and advise you on next steps.

Can a deficiency increase your risk of certain diseases?

If you are deficient in B vitamins, you may experience a range of symptoms depending on which B vitamin you are deficient in.

If left untreated, deficiencies may increase your risk of:

• Anemia
• Digestive problems
• Skin conditions
• Infection
• Peripheral neuropathy

Vitamin B-12 deficiency, in particular, may increase your risk of neuropsychiatric disorders. Researchers are also studying its role in hyperhomocysteinemia and atherosclerosis.

Babies born to women who lack folic acid during pregnancy are more likely to have birth defects.

Many foods contain B vitamins, making it easy to get enough of them in your diet. It’s best to get your B vitamins from a variety of food sources. This helps ensure you get enough of each type.

You can find vitamin B at:

• Milk
• Cheese
• Egg
• Liver and kidney
• Meat, such as chicken and red meat
• Fish such as tuna, mackerel and salmon
• Shellfish, such as oysters and clams
• Dark green vegetables such as spinach and kale
• Vegetables such as beets, avocados, and potatoes
• Whole grains and cereals
• Pulses such as kidney beans, black beans, and chickpeas
• Nuts and seeds
• Fruits such as citrus, bananas and watermelon
• Soy products, such as soy milk and tempeh
• Blackstrap Molasses
• Wheat germ
• Yeast and Nutritional Yeast

If your doctor recommends increasing your intake of certain B vitamins, review this curated food list:

• Foods rich in vitamin B-6
• Foods rich in biotin
• Foods rich in vitamin B-12
• Vegetarian-friendly foods rich in vitamin B-12

Need anything to add?

Most people get enough B vitamins through their diet. Your diet is also the best way for your body to get these vitamins.

You should not take supplements unless your doctor confirms that you are deficient in a specific B vitamin. They can tell you if you should take specific B supplements or add a B-complex vitamin supplement to your daily routine.

You may be more likely to need a supplement if you:

• Age 50 or older
• Pregnant
• Have certain chronic health conditions
• Vegetarian
• Eat a vegan diet

Supplements are available over the counter at your local pharmacy or health food store.

Supplements are not regulated by the U.S. Food and Drug Administration, so you should only buy them from reputable and reputable brands. This helps ensure that you are taking a high-quality product without any questionable additives. Your doctor may recommend a specific brand to consider.

You should always read all labels carefully and follow any instructions provided by the manufacturer. If you have questions about dosage, ask your doctor.

You are unlikely to get too much B-complex vitamins from your diet. That’s because B-complex vitamins are water-soluble. This means they are not stored in your body but are excreted in your urine every day.

If you take any supplement as directed, you are also less likely to get too much B vitamins.

That said, overdose is possible—especially if you take supplements without getting a diagnosis of the deficiency from your doctor.

Symptoms of vitamin B complex overdose include:

• Excessive thirst
• Skin conditions
• Blurred vision
• Abdominal cramps
• Disgusting
• Vomiting
• Increased urination
• Diarrhea
• Flushing of skin

If you think you have symptoms of a B-complex overdose, seek medical attention immediately.

You should also talk to your doctor if you have been taking supplements and have not been diagnosed with a deficiency. Taking too much B-complex vitamins over the long term can cause nerve damage. This can cause you to lose control of your body movements.

Discuss supplements with your doctor

Always consult your doctor before adding any supplements to your daily routine.

You can discuss your desired health goals and why you think you need supplementation. Your doctor can help you decide if this is the best treatment option and advise you on next steps.

Some supplements can interact with certain underlying diseases and medications, so it's important to let your doctor know.

You should also see your doctor if you think you may be deficient in B vitamins. They can help determine what is causing your symptoms and recommend ways to increase your B vitamin intake if needed.