Vitamin B12 is an essential nutrient that plays an important role in a number of bodily functions, including red blood cell production, nerve function, energy release, and DNA formation. Most healthy people get enough vitamin B12 from food, but 1-2% of people may have a deficiency. Symptoms of a B12 deficiency include fatigue, pale skin, numb or tingly hands or feet, and confusion. The recommended daily amount of B12 for most healthy adults is 2.4 micrograms, and it is found in animal products such as meat, fish, milk, eggs, and clams, as well as fortified breakfast cereals, breads, and grains. Certain populations are more at risk for a B12 deficiency, such as those over 65, vegans and vegetarians, people with gastrointestinal diseases, and people who have had part of their gastrointestinal tract surgically removed. Vitamin B12 supplements may be beneficial for those with a confirmed deficiency, and injections may be necessary if a person doesn't have enough intrinsic factor. While there are no significant health risks with taking vitamin B12 supplements, some medications can reduce B12 levels. Despite some myths, there is no evidence that megadoses of the vitamin can boost energy, help with weight loss, or improve conditions such as Alzheimer's, cancer, heart disease, infertility, age-related macular degeneration, eczema, or sickle cell anemia. If you believe you may have a B12 deficiency, it is important to talk to your doctor about a blood test.
Benefits and Limitations of Vitamin B12