What Are Some Things That Can Cause Defiency of Vitamin B-12?

A vitamin B-12 deficiency can cause fatigue.
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Are you tired all the time, feel short of breath or as if your muscles are much weaker than they used to be? You could be experiencing a vitamin B-12 deficiency. This vitamin is responsible for making new red blood cells and repairing tissue and cell damage. While you take in vitamin B-12 via your diet, a lack of B-12 in the foods you eat is not the only reason your vitamin B-12 levels may be low.


    Your body relies on stomach acid to facilitate vitamin B-12 absorption. Taking medications to reduce stomach acid can affect your vitamin B-12 levels. Examples include proton pump inhibitors to reduce heartburn. Other medications that may reduce vitamin B-12 levels include aspirin and metformin, a drug used to help diabetics control blood sugar.

Pernicious Anemia

    Pernicious anemia is a condition in which your immune system keeps your body from absorbing vitamin B-12 in the foods you eat. Because your liver can store vitamin B-12, you can have pernicious anemia for five to 10 years without experiencing symptoms, according an article published in "American Family Physician" in 2011. If you have pernicious anemia, your physician may recommend vitamin B-12 injections so the vitamin is absorbed into your bloodstream.


    Your body absorbs vitamin B-12 at the end of your small intestine, known as the ileum. If you have conditions that affect your small intestine, such as Crohn's disease, your body may not be able to absorb the vitamin as effectively. If you have undergone previous digestive surgeries, such as ileal resection, in which a portion of your small intestine is removed, or bariatric surgery, your body may not adequately absorb vitamin B-12. Drinking excess amounts of alcohol also can affect your body's ability to absorb vitamin B-12.

Lack of Dietary B-12

    Vitamin B-12 is present in high amounts in animal foods, such as red meat, turkey, fish and shellfish. Eggs, dairy products and chicken contain lower amounts of vitamin B-12. While plants contain some amount of vitamin B12, your body poorly absorbs it. This is why vegetarians and vegans may experience a vitamin B-12 deficiency. You may wish to choose vitamin B-12-fortified foods to increase your levels without having to eat animal products.

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