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Alert: 8 out 10 Indians are vitamin B12 deficient- Vegetarianism and genes may influence B12 levels.

In India, 60-70% of the population is believed to have lower vitamin B12 blood levels, with nearly 80% of urban middle class having this deficiency. Low levels of vitamin B12 contribute to the higher incidence of  vascular diseases and with low folate levels accounting for higher prevalence of hyperhomocysteinemia, (characterised by high levels of protein, homocysteine in the blood ) among  Indians. Hence, vitamin B12 & folate are essential for heart health.

Some of the factors influencing vitamin B12 levels among Indian adults are:

  1.  Diabetes : Diabetics are at higher risk of deficiency of vitamin B12. Metformin, commonly prescribed drug to diabetics, has the tendency to reduce its absorption.
  2.  Vitamin D3 intake: Deficiency of vitamin D3 often leads to drop in vitamin B12 levels. A D3 deficiency inhibits the absorption of calcium. Calcium is essential for transporting B12 to the stomach. Although your diet is sufficient in Vitamin B12 rich foods such as meat & eggs, if your diet lacks vitamin D3, you may suffer a drop in B12.
  3.  Being vegetarian: Vegetarians have a 4.4 times higher risk for vitamin B12 deficiency. Eating a poorly planned vegetarian diet could contribute to the deficiency.
  4.  Antibiotics: Antacids prevent vitamin B12 absorption. Since many people depend on antibiotics to cure a variety of ailments, they often suffer from acidity, and end up taking antacids & this could be contributing to B12 deficiency.

These factors, along with genetic predisposition contribute to vitamin B12 deficiency. Individuals who have difficulty in absorbing vitamin B12 from foods, as well as vegetarians who consume no animal foods, might benefit from vitamin B12- fortified foods, oral vitamin B12 supplements, or vitamin B12 injections.

Genes and vitamin B12


The  FUT2 gene produces a protein involved in the attachment of the bacterium Helicobacter pylori to the gastric mucosa, which in turn inhibits the absorption of vitamin B12. One type of FUT2 is associated with low vitamin B12 blood levels. Individuals who carry this type are about 16% lower than non-carriers. Vegetarian carriers are at an increased risk for vitamin B12 deficiency. Such individuals may benefit from adequate vitamin B12 intake.

Foods rich in vitamin B12


vitaminb12

Cheese, milk, yoghurt, whey powder, yeast extract spreads (marmite) are some of the vegetarian sources of vitamin B12.

Vitamin B12 status is usually assessed via blood test. An elevated serum homocysteine level might also suggest a vitamin B12 deficiency. However elevated methylmalonic acid levels might be a more reliable indicator of vitamin B12 status because they indicate a metabolic change that is highly specific to vitamin B12 deficiency.

Watch out for symptoms such fatigue, skin pigmentation, memory loss, tingling in the limbs, cramps, giddiness, palpitations, mouth ulcers and loss of energy that are usually associated with vitamin B12 deficiency.

Want to know what type of FUT2 gene you have? Try Xcode’s nutrigenetics test which can tell you what versions of the FUT2 gene are in your DNA. You can also learn about how your genes may influence other traits, including your risk for certain diseases. Write to us at info@xcode.in to find out more.

Janani Thiru
Janani Thiru
Janani is a Nutrigenetic Counselor at Xcode, Freelance Writer, Food Scientist and Nutritionist by academics. She received the prestigious Erasmus Mundus Award by the European Commission for her post graduate program in Food Science and Technology in 2010. She worked with Food & Agriculture Organisation of the United Nations in Rome and Cambodia previously. Her latest project is an e-book of nutrigenetics she is compiling that will be published next year.