Low Cholesterol Diets & Vitamin B-12 Deficiency

Diets low in saturated fat and cholesterol are generally encouraged for people with high blood levels of LDL or "bad" cholesterol and are considered healthful in general. Since such diets limit intake of animal products, it is possible if taken to extremes that they could lead to vitamin B-12 deficiency. Vitamin B-12 only occurs naturally in animal products.

Vitamin B-12 Requirements and Sources

The daily intake of vitamin B-12 recommended by the Food and Nutrition Board is 2.4 mcg per day for adults. Natural sources include meat, fish, dairy products and eggs. Beef, fish and shellfish tend to be especially rich sources. Many cereals are supplemented with B-12. The U.S. Department of Agriculture provides a Nutrient Database for Standard Reference, which lists B-12 content of various foods.

Low Cholesterol Diets and B-12

Diets devoid of any animal products tend to lead to B-12 deficiency. For this reason many vegans take a multivitamin with B-12 or a B-12 supplement. Low cholesterol diets do not necessarily require eliminating all animal products but they may limit B-12 intake.

Fish and shellfish consumption is encouraged on many diets designed to lower LDL cholesterol levels. Although these foods do contain cholesterol, they are low in saturated fat and rich in heart-healthy omega-3 fatty acids so they have a beneficial effect on the overall blood lipid profile. A 3 oz portion of salmon provides almost 5 mcg of B12. Small quantities of lean meats and low fat dairy products can also be consumed on most low cholesterol diets. A half chicken breast contains 0.3 mcg B12 while one cup of 1 percent fat milk provides 1.1 mcg. Supplemented cereals are generally in the 1.5 to 6.0 mcg range. If you think your B12 intake is below 2.4 mcg per day, you may wish to consult with your doctor about taking a supplement. Most multivitamins supply 100 percent of the daily B12 requirement.

Other Factors Affecting B-12 Status

Sometimes as people age they lose the ability to absorb vitamin B-12. According to a study published in the April 2004 "Journal of Clinical Epidemiology," long-term use of acid blockers may lead to B12 deficiency since stomach acid helps release B12 from food proteins. Vitamin B12 is stored in many tissues so it can take years for a deficiency to develop from inadequate intake or absorption.

Signs of B-12 Deficiency

Vitamin B-12 deficiency results in pernicious anemia also known as megaloblastic anemia, which can cause fatigue. In this type of anemia, the red blood cells are larger than normal due to decreased cell division. Vitamin B-12 deficiency can also cause loss of the myelin sheath that coats nerves resulting in peripheral neuropathy. For people who take supplemental folate in the form of a multivitamin, megaloblastic anemia may not occur, making the B-12 deficiency more difficult to diagnose.