When would a person need a vitamin B12 supplement?
Q: Should I be taking a vitamin B12 supplement?
A: B12 (also known as cobalamin) is essential for keeping your brain and nerves healthy and for making DNA and red blood cells. We typically get B12 through diet. Rich sources include beef, liver, clams, poultry, fish, fortified cereals, eggs, cheese, yogurt, milk and fortified plant milks (like soy, almond or rice milks).
For us to digest B12, we first have to shake it loose from these foods. Stomach acid helps do that. The freed-up vitamin then binds to a protein (intrinsic factor, produced by cells in the stomach lining) and makes its way to the small intestine, where it’s absorbed into the bloodstream.
An estimated 3.2% of adults ages 50 or older have very low B12 levels, and up to 20% may have borderline deficiency. Aging is often the cause. We tend to produce less stomach acid as we get older. That makes it harder to extract B12 from food.
Other causes of B12 deficiency include taking heartburn medications that suppress stomach acid, eating a diet that does not include animal products, weight loss surgery and an autoimmune disease that attacks the stomach lining or gastrointestinal tract.
How can you tell if you’re low in B12? The first signs of deficiency can be present but so subtle that they are not recognized. For example, you may have muscle weakness that you chalk up to other causes.
Symptoms of full-blown B12 deficiency include:
- numbness or tingling in the hands and feet (due to nerve damage)
- balance problems
- extreme fatigue or muscle weakness
- memory loss or confusion.
Should you get checked for B12 deficiency? Checking B12 levels in the blood is not routine, but it may be a good idea in our older years. Blood tests look for markers of anemia, low levels of B12, and high levels of homocysteine and methylmalonic acid (MMA). A high blood level of MMA is the best indicator of deficiency.
Treating B12 deficiency could be as simple as eating more B12-rich foods. However, people who have had weight loss surgery or regularly take stomach acid blockers will need a vitamin B12 supplement. In supplement form, B12 isn’t bound to the food, so you don’t need stomach acid to extract it. I usually recommend an over-the-counter B12 pill of 1,000 micrograms daily.
People with classic pernicious anemia caused by an autoimmune disorder don’t make enough intrinsic factor. For people with this problem, B12 pills may not work, and injections of B12 may be required.
Is a supplement warranted if you’re not deficient? It surely is if you don’t eat animal products, and it’s a good idea for all older individuals. Deficiency can be prevented at a very low cost and low hassle by taking a daily multivitamin.