The vitamin aisle at your local drugstore is packed with different options and it can be hard to wade through them all to find what you might actually need. What's more, some supplements are better understood than others: While you may understand the benefits of iron, calcium, and vitamin D, chances are you're a little less familiar with vitamin B12 supplements and what they do.

The vitamin has gotten some buzz in the past decade or so after celebrities including Rita Ora, Justin Timberlake, and Madonna were reported to have tried injections to boost their B12 levels. Katy Perry even once tweeted about getting a B12 shot in her butt. So what's the deal with B12, and is it deserving of the celebrity hype? Here's what to know about the purpose of the vitamin, how to tell whether you might be deficient in it, and what to do if you are.

What is B12, exactly?

Vitamin B12 is a water-soluble micronutrient that's found naturally in many animal foods that you eat, nutritionist Keri Gans, author of The Small Change Diet, tells Allure. There are actually several forms of B12, but all of them contain the mineral cobalt, per the National Institutes of Health (NIH).

As New York City-based nutritionist Gina Keatley tells Allure, the vitamin is involved in metabolism with every cell of your body and has a big impact on DNA synthesis. According to nutritionist Beth Warren, founder of Beth Warren Nutrition and author of Living a Real Life with Real Food, B12 also helps create red blood cells. Keatley adds that since we don't produce B12 on our own, we have to get it from our diets; it's produced by bacteria in the gut and when we consume certain animal foods, we get the B12 produced by the gut bacteria of those animals.

So how much B12 do I need?

Your B12 needs depend largely on your age and whether you're pregnant or breastfeeding. Women who are 14 years old and up generally need about 2.4 micrograms of B12 a day, according to the NIH. If you're pregnant, your needs go up to 2.6 micrograms a day, while you'll need 2.8 micrograms a day if you're breastfeeding, the organization says.

To help put that into perspective, one cup of low-fat milk contains 1.2 micrograms of B12, while some fortified breakfast cereals have up to six micrograms. So essentially, you should be able to get more than your daily recommended intake just by having a bowl of cereal with milk for breakfast.

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How can I know if I'm not getting enough B12?

B12 is a pretty common vitamin deficiency, impacting up to 15 percent of the general population, per the NIH. There are a few health conditions that make it more likely that you'll struggle with this, Warren says. Those include Crohn's disease, celiac disease, Graves' disease, and lupus.


However, it's also possible for you to struggle with a B12 deficiency even if you don't have an underlying health condition. Strict vegetarians and vegans are also at a higher risk of developing a B12 deficiency than lacto-ovo vegetarians (vegetarians who still eat eggs and dairy products) and non-vegetarians, according to the NIH.

Gans says that if you're not getting enough B12 on a regular basis, you could suffer from vitamin deficiency anemia, a condition in which your blood lacks enough healthy red blood cells. This can lead to numbness and tingling in your hands and feet, mental confusion, weight loss, and generally feeling wiped out and weak, as reported by the Mayo Clinic. If you suspect that you're deficient in B12 Warren recommends that you talk to your doctor, who can order a blood test to help determine if that's the case.

How can I add more B12 to my diet?

Most people get enough B12 from the foods they eat "without thinking about it," Gans says. She points to animal products like beef, poultry, fish, eggs, and dairy as B12-rich items, adding that some foods — including breakfast cereals, some non-dairy beverages (like almond and soy milk), and meat substitutes — are fortified with it. "It's best to read nutrition labels to check," she says.

Of course, some foods have more B12 than others: The NIH reports that clams are packed with the vitamin at 84.1 micrograms per three-ounce serving, while liver also contains a fair amount. But again, if you're a vegan or follow a strict vegetarian diet, it can be hard to get enough B12 in your diet.

What are B12 injections, and should I try them?

Yes, B12 injections may have had a moment in the spotlight, but it's not really advisable (or necessary) for the average person, Keatley says. If you're not getting enough B12 in your diet, injections may be helpful; if you are, they're unlikely to do anything. What's more, being deficient in B12 doesn't mean you automatically have to have regular shots since some people do just fine with supplements in pill form, Keatley says. But if you have pernicious anemia (that is caused by a B12 deficiency) or have any other trouble absorbing B12, injections might be a good idea for you, Warren says.

What happens if you get too much B12?

If you're taking B12 supplements and you accidentally take more than one in a day, nothing bad is going to happen to you. "Since B12 is a water-soluble vitamin, there really is no such thing as too much," Gans says. "Your body will use what it wants and eliminate the rest."

If you're interested in taking a B12 supplement, it's a good idea to talk to your doctor first because B12 supplements can interact with some medications like chloramphenicol (a type of antibiotic) and metformin (which is used to treat diabetes) or simply may not be necessary for you. A conversation with your doctor should help steer you in the right direction.

If you discover that you are B12 deficient, your doctor will determine how much extra B12 you need, as well as which supplement will work for you. Here are a few to consider.

1. Jarrow Formulas Methyl B-12 500 mcg Lozenges

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If you like your vitamins with a little flavor, check out this cherry formula, which is suitable for vegans and vegetarians alike. You can dissolve these lozenges on your tongue or chew them.

$6 (Shop Now)

2. Nature Made Energy B12 1,000mcg Adult Gummies Cherry & Wild Berries

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If gummies are more your style, then Nature Made makes some admittedly delicious fruit-flavored ones. Keep in mind that these contain gelatin, which isn't an acceptable ingredient for vegetarians.

$14 (Shop Now)

3. Nature's Bounty Methylcobalamin Vitamin B-12 1000 mcg

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If you're looking for something simple, Nature's Bounty has you covered with these vegetarian-friendly tablets, which are free of artificial flavors and colors and coated for easy swallowing.

$12 (Shop Now)

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