What Dosage Of B12 Vitamins Does A Person Need?

Vitamin B-12 helps the body make the DNA contained in your cells and is required for healthy nerves and tissues. Vitamin B-12 also ensures that the body can produce healthy red blood cells. Vitamin B-12 belongs to a group of vitamins called water-soluble vitamins. It is the only vitamin in this group that can be stored in the body.

Daily Recommendations

The Recommended Dietary Allowance, or RDA, for vitamin B-12 depends on your age. Infants require 0.4 to 0.5 mcg of vitamin B-12 daily. Children between the ages of 1 and 3 require 1.3 mcg, children between 4 and 8 require 1.2 mcg and children between 9 and 14 require 1.8 mcg daily. Adolescents and adults aged 14 and older require 2.4 mcg of vitamin B-12 daily.

Deficiency

Because the body is able to store vitamin B-12, deficiency of the vitamin is rare. According to MayoClinic.com, it can take several years for you to deplete the vitamin B-12 stores in your body. If you regularly do not consume enough vitamin B-12, however, stores can become depleted. This can lead to a condition called pernicious anemia, which is characterized by a lack of healthy red blood cells. Pernicious anemia can cause fatigue and shortness of breath. It can also lead to nerve damage, which can cause tingling, numbness, muscle weakness and difficulty walking.

Toxicity

Large doses of vitamin B-12 have not been shown to cause any adverse health effects. According to the Linus Pauling Institute, this may be due to the fact that only small amounts of vitamin B-12 can be absorbed by the body, even when taken in large doses. Because it does not have the potential for toxic effects, the Food and Nutrition Board has not set an upper tolerable intake level for vitamin B-12.

Considerations

Certain drugs and medications can reduce the absorption of vitamin B-12. Proton pump inhibitors and other medications used to treat gastroesophageal reflux disease decrease the levels of vitamin B-12 in your blood. Medications used to control type 2 diabetes can also decrease the absorption of vitamin B-12 in your body. If you are taking any of these medications, you may need to increase your intake of vitamin B-12. You should talk with your health care provider or dietitian to determine your specific vitamin B-12 needs.

Food Sources

Although vitamin B-12 supplementation can help prevent vitamin B-12 deficiency, it is best to get most of your daily intake through food. The best food sources of vitamin B-12 include meat, fish, poultry and low-fat dairy products. Fortified grains and cereals can also provide a significant amount of vitamin B-12.