ZocdocAnswersDoes B12 help you lose weight?

Question

Does B12 help you lose weight?

I'm a guy in my mid 30s whose weight has been out of control for as long as I can remember. I heard from a friend that the B12 shot can help you lose weight by keeping your energy levels up. Is this true? Is it completely safe?

Answer

Vitamin B12 is a very important factor in your body's metabolism. It acts through the processes that make DNA and is required in this process. The production of red blood cells is directly linked to the production of DNA. Thus, people without enough vitamin B12 will have a tougher time make red blood cells. This leads to anemia, which can cause fatigue. This is probably why vitamin B12 has the reputation of increasing energy levels because those that are deficient in the vitamin become anemic which is reversed by vitamin B12 shots. Supplementing the vitamin through shots will only help you if you have a deficiency. I must say that vitamin B12 deficiency in someone your age is extremely rare. There are 3 types of people that get deficient in vitamin B12. 1. Strict Vegans for many years (the vitamin is found in meet), 2. people that have had part of the small intestine surgically removed, and 3. people with pernicious anemia (an autoimmune disease seen mostly in older folks). Plus the body keeps years worth or reserve vitamin B12 around meaning that you would have to have had one of these problems for a long time. I suggest that you schedule an appointment with your primary care physician (family doctor or internal medicine doctor). You can have a blood count done to make sure that you are not anemic. In addition, you should have an in depth discussion about your weight and come up with some strategies to get the weight off. Good luck.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

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