There’s no solid proof that vitamin B-12 shots, also called injections, help you lose weight.

Vitamin B-12 is a water-soluble B complex vitamin. It’s found naturally in many foods, such as meat, fish and dairy products. Vitamin B-12 is added to some foods and is available as a dietary supplement. Health care providers commonly prescribe vitamin B-12 shots to help prevent or treat pernicious anemia and B-12 deficiency.

Some researchers have studied vitamin B-12 to find out if it can raise energy and endurance during exercise. But there isn’t evidence to prove this. And unless you have low vitamin B-12 levels in your body, vitamin B-12 shots aren’t likely to give you more energy or improve your performance.

Metformin (Fortamet, Riomet, others) is a drug that may be used as part of a weight-loss tool for people with type 2 diabetes. Low vitamin B-12 levels in your body can be a side effect of this drug. If you take metformin, talk to your health care provider about ways to keep enough vitamin B-12 in your body.

Getting large amounts of vitamin B-12 through vitamin B-12 shots is not likely to harm your health. But vitamin B-12 may affect how well some drugs work. And some drugs can affect vitamin B-12 levels. So if you want to get vitamin B-12 shots, tell your health care provider first.

If you’re hoping to lose weight, avoid giving in to quick and easy fixes. What counts is a healthy lifestyle. Enjoy healthier foods in proper portions. And get physical activity every day.

 

From Mayo Clinic to your inbox

Sign up for free, and stay up to date on research advancements, health tips and current health topics, like COVID-19, plus expertise on managing health.

To provide you with the most relevant and helpful information, and understand which
information is beneficial, we may combine your email and website usage information with
other information we have about you. If you are a Mayo Clinic patient, this could
include protected health information. If we combine this information with your protected
health information, we will treat all of that information as protected health
information and will only use or disclose that information as set forth in our notice of
privacy practices. You may opt-out of email communications at any time by clicking on
the unsubscribe link in the e-mail.