A multivitamin may prevent the low vitamin B-12 levels that are sometimes caused by metformin, a drug used by millions of people with diabetes.
In a study of roughly 2,500 people aged 50 or older, 16 percent of metformin takers who took no multivitamin—but only 4 percent of those who took a multi—had low or borderline B-12 blood levels. (A typical multi has 6 to 25 micrograms of B-12.)
People without diabetes who took a multi were also less likely to have low B-12.
Why that matters: a B-12 deficiency can cause anemia and irreversible nerve damage that can masquerade as dementia.
What to do
Anyone 50 or older—and especially metformin takers—should get at least 2.4 micrograms of B-12 a day from a B-12 supplement, a multi, or a fortified food. Some older people have too little stomach acid to digest and absorb the B-12 that occurs naturally in meats, eggs, and dairy foods.
Vegans (who eat no animal foods) should also take a B-12 supplement.
Even B-12 supplements with 1,000 mcg are safe.
- Why most chewable and gummy multivitamins may not be a good choice
- Test your knowledge of multivitamins with this short quiz
- Can multivitamins protect you from cancer?
Photo: © aduchinootonosama/fotolia.com.
Find this article interesting and useful? Nutrition Action Healthletter subscribers regularly get science-based advice about diet and diabetes, heart disease, cancer, osteoarthritis, and other chronic diseases; delicious recipes; and detailed analyses of the healthy and unhealthy foods in supermarkets and restaurants. If you don’t already subscribe to the world’s most popular nutrition newsletter, click here to join hundreds of thousands of fellow health-minded consumers.