Should I take a magnesium supplement? Here’s what the science says.
What is vitamin B12 good for?
- Fatigue caused by anemia. People often think of anemia caused by iron deficiency, but low B12 can classically lead to an anemia where the blood cells become abnormally large.
- Certain neurological symptoms, such as trouble walking, numbness or psychiatric issues, because of a deficiency.
How do I know if my B12 is low?
- Older adults. Around 15 percent of Americans over age 65 have a deficiency related to reduced acid in the aging stomach, which makes it harder to absorb the vitamin B12 that’s naturally present in foods. Elderly people are generally able to absorb oral supplemental B12 or vitamin B12 in fortified foods without the same issue.
- Vegans or vegetarians. In one small study, 40 percent of vegans were found to be vitamin B12 deficient.
- Pernicious anemia or other autoimmune conditions. In pernicious anemia, the body produces antibodies that interfere with vitamin B12 absorption. These patients should take lifelong vitamin B12 therapy. Vitamin B12 deficiency is also more common among those with other autoimmune conditions such as vitiligo or thyroiditis.
- Gastrointestinal surgery. People with a history of gastric bypass or other surgeries or diseases (like celiac or Crohn’s) that affect particular areas of the intestine can be at higher risk.
- People on certain long-term medications such as metformin and acid-reducing medications. These are known to reduce absorption of B12.
How can I increase my B12 naturally?
What’s the best way to absorb vitamin B12?
Is there any harm in taking vitamin B12?
What I want my patients to know
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