Vitamin supplements are very popular. 

Supplementing with vitamin B12 is particularly common, because deficiency is widespread. 

B12 shots help with energy levels, brain function and weight loss.

What is Vitamin B12 and What Does it Do? 

Vitamin B12 is a water-soluble vitamin, also known as cobalamin.

It plays a vital role in brain function and the production of DNA and red blood cells.

Chemically, vitamin B12 can exist in a number of different forms, but all of them contain the mineral cobalt.

The vitamin can be stored in the liver for a long time, so it may take a few years for a deficiency to develop.

Bottom Line:

Vitamin B12 is a water-soluble vitamin that plays an important role in brain function and red blood cell production.

Deficiency is common, especially in people who follow a vegetarian or vegan diet.

In fact, it's thought that up to 90% of people following these diets have a deficiency. This is because B12 is only found naturally in animal foods.