Vitamin B12 Can Protect Against Alzheimer's, More Evidence Suggests

Beef liver is one of the most vitamin B12-rich foods, with 800 percent of our daily recommended value. (Image credit: Vlad Ageshin | Dreamstime)

Vitamin B12 could help protect against Alzheimer's disease, a new study suggests.

"Even a relatively small change in [vitamin B12] can significantly affect the risk" of developing Alzheimer's disease , study researcher Dr. Babak Hooshmand, of the Karolinska Institute in Sweden, told MyHealthNewsDaily.

When the body has normal levels of vitamin B12, it's able to counter the effects of a compound in the blood called homocysteine, which at high levels, is associated with Alzheimer's disease and stroke, Hooshmand said.

Vitamin B12 is most commonly found in fish , meat and fortified cereals. It's also gained popularity over the last few years because of its putative energy-increasing effects, but there's no evidence that taking supplements increases energy levels in people who aren't deficient in the vitamin, according to the National Institutes of Health.

And eating foods naturally high in B12 is a better way to get the vitamin than taking any supplement, drink, shot or injection, Hooshmand said.

The study will be published tomorrow (Oct. 19) in the journal Neurology.

Blood tests and B12

Researchers monitored 271 Finnish people, ages 65 to 79 , who did not have dementia. By the end of the seven-year study, 17 people developed Alzheimer's disease .

Blood samples were taken from everyone in the study, and researchers monitored their homocysteine and vitamin B12 levels. None of the people in the study took B12 supplements.

The researchers found even a tiny increase in vitamin B12 had a profound impact on decreasing the risk for Alzheimer's disease, Hooshmand said.

The results held true even after taking age, gender, blood pressure, weight and smoking status into account.

Brains and B12

The findings support other research done on the effects of B12 on memory. In 2004, a study published in the journal Neuropsychology found, among older people already at risk of developing Alzheimer's disease, those with vitamin B12 deficiencies performed more poorly on memory tests than those with normal B12 levels.

And in a September study in the journal PLoS One, University of Oxford scientists found vitamin B12 supplements slowed the rate of brain shrinkage in older adults with mild cognitive impairment, a precursor to Alzheimer's disease.

Hooshmand said his new study would need to be repeated with a larger group of participants before it could impact clinical practice.

Studies also need to be done to test whether vitamin B12 supplement interventions make a difference in decreasing the risk of Alzheimer's disease, he said.

Amanda Chan
Amanda Chan was a staff writer for Live Science Health. She holds a bachelor's degree in journalism and mass communication from the Walter Cronkite School of Journalism and Mass Communication at Arizona State University, and a master's degree in journalism from Columbia University.