B12 Deficiency Can Be Serious

Even as in the last issue we discussed recent, increased vitamin D deficiency overdiagnosis ( call it “vitamin D sufficiency”), there can of course be legitimate gaps in our nutrition that are far more common than others. One deficiency with many causes that can lead to health trouble is vitamin B12 deficiency.

Vitamin B12 helps the body manufacture red blood cells and nerves; it also helps with DNA maintenance and other functions. The current recommended intake for B12 is, for the average adult, 2.4 micrograms per day. Like most vitamins, B12 can’t be made by the body and so is classified as an “essential” vitamin. Some people don’t consume enough vitamin B12 to meet their needs, while others can’t absorb enough, no matter how much they consume.

Vitamin B12 deficiency is therefore relatively common, especially among older people. The National Health and Nutrition Examination Survey (NHANES) estimates that 3.2% of adults over age 50 have a seriously low B12 level, and up to 20% may have a borderline deficiency.

What are the possible health outcomes of B12 deficiency?
According to a case report from Massachusetts General Hospital published in NEJM, over the course of two months, one 62-year-old man developed pins and needles sensations in his hands, had trouble walking, suffered severe joint pain, became progressively short of breath and turned yellow. The cause was lack of vitamin B12 in his bloodstream. Worse than all of this, a severe vitamin B12 deficiency can also lead to deep depression, paranoia and delusions, memory loss, incontinence, loss of taste and smell and more.

Who is at risk for B12 deficiency?
Of the many causes of B12 deficiency, two of them can confound us because they are practices frequently undertaken to improve health: a vegetarian diet and weight loss surgery.

It’s important to remember that plants don’t make vitamin B12. The only foods that deliver it are meat, eggs, poultry, dairy products and B vitamin-enriched pastas and cereals. Strict vegetarians and vegans are at high risk for developing a B12 deficiency if they don’t eat grains that have been fortified with the vitamin or take a vitamin supplement. But the popular gluten-free and low carbohydrate diets that have been embraced by millions of people in recent years can eliminate even these supplemental sources of B vitamins that would otherwise be consumed.

People who have stomach stapling or other form of weight-loss surgery are also more likely to be low in vitamin B12 because the operation interferes with the body’s ability to extract vitamin B12 from food.

Conditions that interfere with food absorption, such celiac or Crohn’s disease, can cause B12 trouble (as well as necessitate dietary modifications that can interfere with B12 intake, like eliminating foods containing gluten). Note too that use of commonly prescribed acid reflux medications can interfere with the stomach acids needed to absorb vitamin B12. The condition is more likely to occur in older people due to the cutback in stomach acid production that often occurs with aging.

How to recognize a B12 deficiency
Vitamin B12 deficiency can manifest both fairly quickly or very gradually. The condition can also be overlooked or confused with something else since the symptoms are wide-ranging. These may include:

  1. strange sensations, numbness or tingling in the hands, legs or feet
  2. difficulty walking (staggering, balance problems)
  3. anemia
  4. a swollen, inflamed tongue
  5. yellowed skin (jaundice)
  6. cognitive difficulties and memory loss
  7. paranoia or hallucinations
  8. weakness
  9. fatigue

After a clinical evaluation a blood test is needed to confirm the condition. Early detection and treatment are important. Untreated B12 deficiency can cause severe neurologic problems and blood diseases.

When to check your level
You should ask your doctor to check your B12 level if you:

  1. are over 50 years old
  2. take a proton-pump inhibitor (such as Nexium or Prevacid) or H2 blocker (such as Pepcid or Zantac)
  3. take metformin (a diabetes drug)
  4. are a strict vegetarian
  5. have had weight-loss surgery or have a condition that interferes with the absorption of food

A serious vitamin B12 deficiency can be corrected two ways: weekly shots of vitamin B12 or daily high-dose B12 pills. A mild B12 deficiency can be corrected with a standard multivitamin. Preventing a B12 deficiency is not difficult for many people who may otherwise be at risk. If you are a strict vegetarian or vegan, it’s important to eat breads, cereals or other grains that have been fortified with vitamin B12, or take a daily supplement. A standard multivitamin delivers 6 micrograms, well above the determined daily need of 2.4 micrograms.

If you are over age 50, the Institute of Medicine recommends that you get extra B12 from a supplement, since you may not be able to absorb enough through food. Once again, Aa standard multivitamin usually will suffice.

B12 is not really a cure
It’s worth mentioning that vitamin B12 is increasingly oversold as a cure or preventive strategy for many conditions. The internet is full of pseudoscience claiming that vitamin B12 can prevent Alzheimer’s disease, heart disease and other chronic conditions. There are websites devoted to B12 supplementation to reverse infertility, eczema and a long list of other health problems. There is no basis for many of these overreaching conclusions.

Harvard health points out, for example, that although B12 deficiency can be associated with cognitive decline, the leap to B12 supplementation as a means to prevent Alzheimer’s disease is unfounded. Clinical studies involving people with Alzheimer’s disease have not shown improvement in cognitive function, even doses of the vitamin as high as 1,000 micrograms. Plan to get enough vitamin B12 to prevent a deficiency, and avoid turning to the vitamin as a remedy for whatever ails you.

Harvard Health, Oct. 2016, “Vitamin B12 deficiency can be sneaky, harmful,” http://tinyurl.com/kfqhcv6

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