Define Vitamins B-12 & B-6

The B vitamins are eight water-soluble vitamins that help the body get energy from food and make red blood cells. While water-soluble vitamins usually can't be stored, vitamin B12 is stored in the liver. The vitamins B6 and B12 prevent a type of anemia. They also may have a role in keeping your heart healthy, reports the American Heart Association.

Function

Vitamin B12 is needed for proper red blood cell formation, neurological function and DNA synthesis, according to the National Institutes of Health Office of Dietary Supplements. Vitamin B6 is involved in protein metabolism and red blood cell metabolism. The nervous systems and immune systems also require vitamin B6. Vitamin B6 is needed for the conversion of tryptophan, an amino acid, into niacin, a vitamin. It is required to make hemoglobin, a protein in red blood cells that carries oxygen. Vitamin B6 also helps keep your blood sugar in the normal range.

Homocysteine

Vitamins B12 and B6, along with folate, help convert the amino acid homocysteine into methionine. Without enough vitamin B12 and B6, homocysteine levels increase, and this increase can lead to heart attack, stroke and peripheral vascular disease, according to the American Heart Association. Homocysteine may damage the inner lining of arteries and promote blood clots, leading to increased risk of atherosclerosis. Randomized trials are needed to determine if vitamin B12 and B6 supplementation will decrease risk.

Anemia

Vitamin-deficiency anemia occurs when the body doesn't have enough vitamin B12, vitamin B6 or folate. Anemia refers to a below-normal level of hemoglobin, a protein in red blood cells that carries oxygen to all parts of the body, states the National Anemia Action Council. Anemia can be temporary, a result of other health problems or a chronic condition. People with mild anemia may not experience any symptoms at all, but if the anemia become severe enough, they may find it difficult to carry out daily activities, feel tired or experience shortness of breath. Vitamin-deficiency anemia is most common in older adults, according to the National Anemia Action Council. Vitamin B6 deficiency is often a result of not consuming enough foods that contain the vitamin or by taking certain medications. Vitamin B12 is usually caused by your body not being able to absorb the vitamin, although a deficiency can occur in strict vegetarians or those who rarely consume meat, eggs or milk.

Foods

Vitamin B12 is present in animal products, including meat, fish, eggs, poultry, milk and milk product. Vitamin B6 is found in a wide variety of foods, including fortified cereals, meat, fish, poultry, beans and some fruits and vegetables. Foods that are high in both vitamin B6 and vitamin B12 include fortified cereals, liver, salmon, mackerel, cod, tuna, herring, eggs, beef and pork, reports the NIH Office of Dietary Supplements.

Recommendation

According to the NIH Office of Dietary Supplements, the Recommended Dietary Allowance, or RDA, of vitamin B6 for adults is 1.3 mg per day. After age 50, females should get 1.5 mg, and males should get 1.7 mg. The RDA for vitamin B12 is 2.4 mcg per day for adults. If you choose to take supplements, choose amounts of vitamin B12 and B6 that are close to the RDAs. For vitamin B6, don't consume more than the upper tolerable intake level, or UL, of 100 mg per day. More than this amount may cause adverse health effects. No UL has been established for vitamin B12.