Folic Acid and Vitamin B-12: Get Enough of Both

Folate, or its synthetic form, folic acid, is good for brain health. But there’s concern that this brain booster could mask deficiencies in vitamin B-12, which can result in mental decline and other nerve problems. The July issue of Mayo Clinic Health Letter covers why it’s important to have enough of both.

Numerous studies have determined that high levels of folate intake, up to 800 micrograms (mcg) a day, may help ward off cognitive decline, possibly lower the risk of Alzheimer’s disease, and even improve mental sharpness in areas such as memory and mental processing speed.

Folate is also important during pregnancy for the developing fetus, which is why the Food and Drug Administration in 1998 mandated folic acid fortification of grain products sold in the United States.

Vitamin B-12 plays an essential role in red blood cell formation, cell metabolism and nerve function. Where there’s a deficiency, symptoms include persistent tingling in the hands and feet, confusion and forgetfulness.

An estimated 15 percent of older adults are deficient in vitamin B-12. This deficiency can be caused by age-related changes in the digestive tract, which blunt the body’s ability to digest and absorb vitamin B-12 from food. Vegetarians who avoid all animal products and people who have digestive diseases such as celiac disease or Crohn’s disease may also be at increased risk of vitamin B-12 deficiency.

While folic acid offers benefits, there are concerns about how it chemically reacts with vitamin B-12 within the body. It’s suspected that high folic acid intake can correct the anemia — but not the nerve and cognitive deterioration — that would normally occur with vitamin B-12 deficiency. Without the indication of anemia, vitamin B-12 deficiency may not be suspected and neurological deterioration may continue unabated.

More study is needed to fully explore the relationship between folate and vitamin B-12 and how it may affect brain health. Until then, the safest bet is to ensure intake of adequate amounts of both. Most older adults can do this by taking a multivitamin supplement that contains 100 percent of the recommended daily allowance of both folate and vitamin B-12. For folic acid, that’s 400 mcg a day and for vitamin B-12, it’s 2.4 mcg a day.

A healthy diet that includes daily servings of fortified breads, grains or cereals and a wide variety of fresh and natural foods such as fruits, vegetables, beans and nuts can boost daily intake of folate or folic acid to the higher levels that may benefit brain health.