There's no solid evidence that vitamin B-12 injections aid weight loss.
Vitamin B-12 is a water-soluble B complex vitamin found naturally in a variety of foods, including meat, fish and dairy products. Vitamin B-12 is also added to some foods and is available as a dietary supplement. Vitamin B-12 injections are commonly prescribed to help prevent or treat pernicious anemia and B-12 deficiency.
Some weight-loss clinics offer vitamin B-12 injections as part of their weight-loss programs. Proponents of vitamin B-12 injections say the shots give you more energy and boost your metabolism, helping you shed unwanted pounds. But unless you have a vitamin B-12 deficiency, vitamin B-12 injections aren't likely to give you an energy boost.
Metformin (Fortamet, Glucophage, Riomet) is a drug sometimes used as part of a weight-loss strategy for people with type 2 diabetes. Vitamin B-12 deficiency can be a side effect of this drug. If you take metformin, talk to your doctor about strategies to maintain adequate B-12 levels.
Getting large amounts of vitamin B-12 through vitamin B-12 injections isn't likely to harm your health. But vitamin B-12 can interfere with the effectiveness of some medications, so if you receive vitamin B-12 injections, be sure to let your doctor know.
If you're hoping to lose weight, resist the lure of quick and easy solutions. What counts is a healthy lifestyle. Enjoy healthier foods in appropriate quantities and include physical activity in your daily routine.
Aug. 26, 2020
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See more Expert Answers
- Vitamin B12. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed June 2, 2015.
- Vitamin B12: Dietary supplement fact sheet. National Institutes of Health Office of Dietary Supplements. http://ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional/. Accessed June 2, 2015.
- Healthy weight — It's not a diet, it's a lifestyle! Centers for Disease Control and Prevention. http://www.cdc.gov/healthyweight/index.html. Accessed June 2, 2015.
- Metformin in the treatment of adults with type 2 diabetes mellitus. http://www.uptodate.com/home. Accessed June 3, 2015.