What is vitamin B12?

Vitamin B12, or cobalamin, keeps blood and nerve cells healthy, helps make DNA, and plays a key role in energy production. Vitamin B12 is naturally found in most animal foods. It can also be added to foods or supplements.

Vitamin B12 binds to the protein in the foods we eat. In the stomach, hydrochloric acid and enzymes unbind vitamin B12 into its free form. Vitamin B12 is found naturally in a wide variety of animal foods, and manufacturers add it to some fortified foods.

Vitamin B12 benefits

  • Provides energy
  • Aids cognitive and neurologic development
  • Prevents megaloblastic anemia (a blood disorder)
  • Forms red blood cells
  • Improves the function of the central nervous system
  • Aids metabolism
  • Improves cardiovascular health

How much vitamin B12 do you need per day?

Average daily recommended amounts are listed below in micrograms (mcg). 1 milligram (mg) is equal to 1000 micrograms (μg)

  • Adult Women: 2.4 mcg
  • Adult Men: 2.4 mcg
  • Pregnant/Breastfeeding Women: 2.6 – 2.8 mcg

Natural sources of vitamin B12

  • Red meat
  • Fish and shellfish
  • Liver
  • Eggs
  • Poultry
  • Dairy products: milk, cheese, and yogurt
  • Vitamin-fortified nutritional yeast
  • Vitamin-fortified breakfast cereals
  • Enriched soy or rice milk

Learn about vitamin B12 deficiency symptoms.

Further reading: Harvard School of Public Health, National Institutes of Health (1),(2)