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"Can B-12 injections help one lose weight?"

ZocdocAnswersCan B-12 injections help one lose weight?


One of my coworkers is raving about how she lost so much weight after getting a B-12 injection. I've been trying to lose weight and keep it off for a long time, and I'd definitely give the B-12 a whirl if it is safe and has been proven effective. Are either of these things true?


Maintaining a healthy weight is one of the best things you can do for your health. Congratulations on your efforts. I recommend discussing your goal with your primary care doctor before starting any new regimens as he or she can both advise you on the safety as well as help you with your goals. To answer your question--no, there is no evidence that B12 is an effective method for weight loss. These claims are without evidence. B12 (also known as cobalamin) is a vitamin that in naturally found. B12 is used by the body's cells in the replication of DNA--which is the blueprint which the cells use to make new cells and proteins. People who are deficient in B12 get anemia (low blood cells) and can get nerve disease. B12 is found in meat, eggs, milk products and fish. Therefore vegans are occasionally deficient. There is no reason to think extra B12 would make you lose weight. There is some evidence that people who take a multivitamin are more likely to maintain a healthy weight--but this data is controversial. B12 is relatively safe, and there is no commonly known symptoms of too much B12. I would not recommend B12 injections--these carry the risk of the injections (bleeding, infection)--without any known benefit. B12 injections should be restricted to people who are B12 deficient and cannot absorb B12 (some bowel diseases). Talk to your doctor about other, more proven ways to lose weight.

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