B12 shots seem to be all the rage. Celebs and wellness influencers swear by using regular B12 injections to boost energy and mood, fight fatigue, and even clear up their skin. But are these claims legit?

In this article, we break down what B12 shots are, why they’re necessary for some people, and why most people don’t need them.

Vitamin B12 is a nutrient that’s involved in a ton of important bodily functions. For example, you need this vitamin for your nervous system and red blood cells to work correctly.

B12 is found in many foods: fish and shellfish, meat, poultry, yogurt, eggs, and more. But even though you can get B12 from plenty of foods, it’s pretty common to have low B12 levels.

FYI: People with B12 levels under 200 picograms per milliliter (pg/mL) are considered to have a deficiency. A B12 level above 300 pg/mL is considered normal.

Certain factors increase your risk of developing a B12 deficiency, including:

  • restrictive diets low in B12
  • autoimmune diseases and some other health conditions
  • age of 60 or older
  • certain medications (like Metformin and Prilosec)
  • gastrointestinal surgery

Although it’s rare, severe B12 deficiency can result in irreversible damage to your nervous system. Fortunately, B12 deficiency and suboptimal B12 levels can be treated with dietary changes and high-dose supplements or injections.

Many docs choose to treat B12 deficiency with B12 shots because injections avoid the gastrointestinal tract entirely. That’s important for increasing B12 levels in people who can’t properly absorb B12 from food or supplements.

However, research suggests that high-dose oral B12 supplements work just as well as B12 shots for raising B12 levels in people with a deficiency. Plus, B12 injections are generally more expensive than supplements.

In fact, a 2019 study found that sublingual B12 supplements (a form of supplement that you place under your tongue and let dissolve) were more effective than B12 shots for increasing B12 levels. So if you’re looking for a first-line treatment for B12 deficiency, supps are probably the way to go.

B12 shots are associated with several benefits. However, these benefits are related to treatment of low B12 levels with B12 shots. There’s no evidence that B12 shots are helpful for people who already have optimal B12 levels.

Effective for boosting low B12 levels

B12 shots are prescribed to people who have low B12 levels.

If your doc suspects you may have low B12, they’ll recommend lab testing to find out for sure. Depending on your results, they may recommend high-dose oral B12 supplements or B12 injections.

Improves symptoms related to B12 deficiency

B12 deficiency or low B12 level comes with some common symptoms:

  • fatigue
  • paleness
  • headaches
  • swollen tongue
  • diarrhea
  • heart palpitations
  • numbness and tingling in the hands and feet
  • mood changes

If you have a B12 deficiency, increasing your B12 levels (with B12 supplements or shots) can help you feel better over time.

But if your levels are already good, B12 injections won’t give you any additional benefits. Your bod regulates the levels of B12 in your blood, so you won’t build up a reserve. You’ll get rid of any extra B12 through your urine.

tl;dr: Unless you’re actually low in B12, B12 shots aren’t going to do much for you.

B12 supplements and injections are considered safe. Even in high doses, B12 supplements and injections aren’t linked to dangerous side effects.

However, B12 may lead to some more mild side effects, such as diarrhea and swelling. B12 injections could also interact with certain medications. That’s why it’s important to discuss your medical history, including current medications, with your doctor before using a supplement.

B12 injections can also be a bit painful, especially for people without much body fat.

B12 injections should be prescribed by a healthcare professional only as a way to address low B12 levels. (Remember, there’s no evidence that B12 injections benefit people who have optimal B12 levels.)

If you think you might be low in B12, ask a medical professional to perform a blood test. Depending on your B12 levels, they may recommend oral supplements or B12 injections.

If needed, you’ll typically get B12 injections over the course of several months. It’s not a one-and-done thing.

Generally, a healthcare professional will inject the B12 into your muscle. But it is possible that your doc would let you give yourself the B12 injections or have a friend or family member help you. Either way, you’ll need a prescription for B12 shots.

PSA: Be wary if a healthcare pro recommends B12 shots without assessing your B12 levels first.

Your bod needs a steady flow of B12 to function properly. That’s why you need to make sure you’re eating a variety of B12-rich foods.

The following foods are rich in B12:

  • organ meats (like liver)
  • shellfish (like clams and oysters)
  • fish (like sardines and salmon)
  • meat and poultry
  • dairy products (like yogurt)
  • eggs
  • fortified foods (like nondairy milks and cereals)
  • nutritional yeast with added B12

If you’re following a well-rounded diet, you’re prob getting enough B12. But the only way to know whether you have healthy B12 levels is to see a healthcare pro for a blood test.

FYI: Some people do need supplements for various reasons. If you have questions about B12 in your diet or B12 supplements, speak with a qualified health professional like a registered dietitian or doctor.

B12 does a lot for your body, so getting enough in your diet is super important.

Some people may need B12 supplements or injections if they’re not getting enough B12 in their diet or if they have trouble absorbing this nutrient from food.

Even though B12 shots are appropriate for use in those who are low or deficient in this vitamin, there’s no evidence that B12 shots offer any benefits for people with optimal B12 levels.