Vitamin B: What to Know About This Essential Nutrient

Constance Sommer,

Thought much about B vitamins lately? If not, maybe you should.

There are eight varieties of B vitamins. And between them, they support brain health, heart health, DNA development and energy regulation. Plus, they’ve been found to prevent migraines, ward off recurrence of some skin cancers, and even possibly slow the progression of a devastating neurodegenerative disease.

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Some people believe "the B stands for ‘boring,’ " says Mark Moyad, M.D., director of preventive and alternative medicine education at the University of Michigan Medical Center in the department of urology.

The reality, he says, is when you look a little closer, the B vitamins "are one of the most fascinating categories in medicine."

But like other vitamins, they should not be taken on a whim. There's evidence, for example, that too much folic acid (vitamin B9) in supplement form can encourage the growth of cancer cells in older people, and an excess of biotin (vitamin B7) can mess with blood lab results.

"There's some risks to taking supplements," says Debbie Fetter, an assistant professor of nutrition at UC Davis. "They’re not entirely benign," given that they can have side effects and even interfere with other drugs.

Experts recommend checking with your physician before you start any supplement, both to make sure it isn't interacting with something you’re already taking, and to ensure that you’re not consuming excessive amounts of a nutrient you’re getting plenty of in your diet.

This particularly applies to B vitamins. Here's what you need to know about them:

What it does: Thiamine helps to turn the food you eat into the energy your body needs, the National Institute of Health's Office of Dietary Supplements explains. It's especially essential for cell formation and function, and for brain and heart health, adds Sue-Ellen Anderson-Haynes, a Massachusetts-based nutritionist and spokesperson for the Academy of Nutrition and Dietetics.

Foods you can find it in: You’ll find thiamine in yeast, pork, brown rice, beans and lentils, and fortified breakfast cereals. That said, heating these foods can reduce the thiamine content, according to the Mayo Clinic.

How much you should be getting: The National Institute on Aging says men 51 and older need 1.2 milligrams (mg) per day; women 51 and older need 1.1 mg daily.

Who might need a supplement: Most people in the U.S. consume the recommended amounts of thiamine, according to the NIH. However, it's worth noting that up to 20 to 30 percent of older adults may have some degree of thiamine deficiency, so talk to your doctor if you’re concerned. Health care providers may recommend individuals who consume too much alcohol, people with HIV, diabetics and people who had bariatric surgery supplement with thiamine, Anderson-Haynes says.

What it does: It helps break down carbohydrates, proteins and fats, says the Mayo Clinic. And like vitamin B1, it plays a major role in cell growth and function.

Surprising benefits: A high dose can reduce migraine frequency by up to 50 percent, studies show, though researchers aren't sure why.

Foods you can find it in: You’ll find riboflavin in eggs, organ meats, lean meats, low-fat milk, mushrooms, spinach, fortified cereals, breads and grain products, according to the NIH.

How much you should be getting daily: Men 51 and older should aim for 1.3 mg, and women 51 and older should get 1.1 mg, the NIA says. If you’re a migraine sufferer, your doctor may recommend a much higher dose (about 400 mg daily) as a preventive measure.

Who might need a supplement: Vegans, athletes who are vegetarians, and people who don't consume dairy may have trouble meeting the recommended daily amount, the NIH says, and may benefit from a supplement. The same goes for people with a genetic disorder called riboflavin transporter deficiency.

What it does: This one is also important in cell development, again helping to turn the food you eat into the energy you need, Anderson-Haynes says.