What Is the Recommended Intake for B12?

Clams are one of the best sources of vitamin B12.

Most people in the U.S. obtain enough vitamin B12 from their diet to meet the recommended daily intake. But not getting enough can cause tiredness and weakness while increasing the risk of conditions such as anemia, depression and dementia.

Function

Vitamin B12 is a micronutrient that helps protect the body's nerve cells and is necessary for healthy blood, proper enzyme function and the production of DNA. It also helps prevent megaloblastic anemia, a condition that leaves people feeling tired and weak.

Recommendations

The National Institutes of Health's Office of Dietary Supplements states that age affects how much vitamin B12 is needed on a daily basis. Adults require 2.4 mcg. Babies and children require less than that amount, while pregnant or breastfeeding women require more. Some conditions, including alcoholism, kidney disease, stress and worm infections, may increase your vitamin B12 requirement according to Mayo Clinic.

Considerations

Vitamin B12 occurs naturally in many animal products. The Office of Dietary Supplements reports that beef liver and clams are the best source. Products derived from plant foods do not contain the vitamin unless they have been fortified. Many cereal manufacturers now add vitamin B12 to their products. Supplements are also widely available.

References

• National Institutes of Health Office of Dietary Supplements: Vitamin B12
• Mayo Clinic: Vitamin B12 (Nasal Route, Oral Route, Parenteral Route)
• Linus Pauling Institute: Vitamin B12