Vitamin B12 deficiency symptoms are far-reaching and disruptive in the body. Most have heard of nervous system disturbance being related to lack of B12, but many remain unaware of the many roles of B12 in other vital processes. Certain groups are at heightened risk of experiencing deficiency, but everyone can benefit from recognizing how important this vitamin is and taking the necessary steps to ensure that adequate amounts are consumed.

Vitamin B12 Deficiency Symptoms

Part of the nervous system disruption seen with B12 deficiency is a host of cognitive problems that include mood disorders, inability to concentrate, memory problems and psychosis. Neuropathy, or pain that is neurological in origin, can also occur along with migraine headaches and unexplained tingling sensations. Since adequate levels of B12 are needed to produce red blood cells, deficiency can lead to a type of anemia called pernicious anemia. This causes tiredness, weakness, and breathlessness as the body fights against the low red blood cell count and corresponding lack of ability to carry sufficient oxygen throughout the body. Babies born to or breastfed by mothers who are B12-deficient are at risk for severe developmental and neurological problems. Individuals who are moderately low in the vitamin are at increased risk of obesity and difficulty building and maintaining lean muscle mass.

Who is at Risk of Deficiency

A review of nutrition data reveals that vitamin B12 naturally occurs mainly in animal-derived foods such as meat, dairy, and eggs. With a diet that excludes animal foods, people who are strict vegetarians or vegans are at higher risk of experiencing vitamin B12 deficiency symptoms. However, symptoms may not appear for some time after adopting a diet low in the vitamin, because the liver can store a few years' worth of B12. Some diabetes medications interfere with B12 absorption, so diabetics should take care to include plenty of the vitamin in their diets. The elderly are also at higher risk of B12 deficiency due to a higher rate of digestive disorders that reduce absorption of the vitamin.

Sources of Vitamin B12

As mentioned before, the richest sources of Vitamin B12 are dairy, meat, and eggs. The nutrition data of shellfish such as clams and oysters shows that these are some of the richest sources of the vitamin by weight. Second is liver, which is also a powerhouse of other B-vitamins and minerals. Red meat, which includes not only beef but also lamb and venison, also contains large amounts of B12.

Supplemental Forms

The two most common forms of supplemental B12 are cyanocobalamin and methycobalamin. Cyanocobalamin is the most common by far. The supplement is commonly available in tablet or liquid form that is designed for sublingual use, which is preferable in terms of absorption. Swallowing B12 supplements results in a much-inferior rate of absorption. Severe deficiency, particularly in cases of pernicious anemia, are usually treated with injections given by a healthcare professional.