Vitamin B12, also known as cobalamin, is a water-soluble vitamin that plays an important role in many bodily processes, including the production of red blood cells and DNA, as well as the proper function of the nervous system. It is primarily obtained through the diet, and can be found in animal products such as meat, fish, and dairy.

Vitamin B12 deficiency is a common health problem, particularly among older adults and vegetarians or vegans who do not consume animal products. Symptoms of vitamin B12 deficiency can include fatigue, weakness, tingling or numbness in the hands and feet, and difficulty with balance and coordination.