Vitamin B12

Vitamin B12 is a nutrient that your body requires for optimal health. It’s needed to make red blood cells, to help your nervous system work properly, and to synthesize DNA, which is the genetic material in all your cells. Vitamin B12 is found in meat and dairy products.

A deficiency of this vitamin is extremely rare, since the body can store several years worth. People who are at risk for vitamin B12 deficiency include the elderly, vegetarians who do not eat meat or dairy products, and people who have trouble absorbing vitamin B12 from their stomachs or small intestines. Those who have trouble absorbing vitamin B12 include people with a disease called pernicious anemia, people who use medicine for heartburn and ulcers over the long term, and people who have had surgery on their stomachs or intestines.

If your vitamin B12 level is slightly low, you probably will not have any symptoms. But if your level of the vitamin becomes significantly low, you may develop anemia, dementia, depression, or problems with your nervous system people who have a low level of vitamin B12 and a high level of homocysteine, an amino acid in the blood, may have a greater risk of heart disease and stroke.

If your doctor diagnoses you with low vitamin B12, you will need to take special vitamin B12 pills, because over-the-counter multivitamins do not contain enough of this vitamin for people who are deficient in it. There is also a vitamin B12 shot, which is usually given every 1 or 2 days for 2 weeks, then once a month thereafter.

Additional Facts

• Elderly people with low levels of vitamin B12 may have an increased risk of brain atrophy, or shrinkage, which is associated with Alzheimer’s disease and decreased cognitive function.
• To take in a day’s supply of vitamin B12, you could eat one chicken breast, one hard-boiled egg, and 1 cup of plain low-fat yogurt, or have 1 cup of milk and 1 cup of bran cereal.
• Some people with vitamin B12 deficiency experience burning sensations in their hands and feet as the first symptoms. This is called peripheral neuropathy and may have other causes as well.