October 15, 2025
Eating a diet rich in riboflavin, a B vitamin, may substantially lower your dementia risk, according to a new report that looked at the effects of B vitamins on brain health. The study found that older adults who ate diets containing the highest amounts of riboflavin, also known as vitamin B2, had a 49 percent lower risk of developing disabling dementia than their peers who ate the least. Diets rich in two other B vitamins, folate and B6, had a less significant impact on lowering dementia risk.
For the study, researchers in Japan looked at 4,171 men and women who were enrolled in the Circulatory Risk in Communities Study, an ongoing study examining the role of diet and lifestyle factors in heart and brain health. They ranged in age from 40 to 69 and lived at home. Participants filled out detailed questionnaires about the foods and drinks they typically consumed.
The researchers followed them for about 15 years. During that time, 887 developed Alzheimer’s disease or other forms of dementia that were serious enough to require daily care.
The researchers considered various factors that may affect brain health, including age, smoking and drinking habits, and other medical conditions such as stroke. They concluded that of various types of B vitamins, riboflavin had the greatest overall impact on the likelihood of developing dementia, cutting risk by almost half. Diets rich in folate and vitamin B6 reduced risk by about 20 percent.
Dietary levels of vitamin B12 were not tied to dementia risk, although deficiencies of this vitamin are common in older people, who are less able to absorb the nutrient from foods. Very low levels of B12 are known to be tied to cognitive problems, and doctors often prescribe B12 supplements to people who are deficient in this vitamin. The study, published in the European Journal of Clinical Nutrition, did not evaluate dietary supplement use among the participants.
B vitamins are known to be essential for the health of the brain and nervous system, though studies are mixed on whether taking B vitamin supplements can help to protect the aging brain against Alzheimer’s disease. Experts generally agree that unless you are truly deficient in specific vitamins—your doctor can test your levels—eating a varied diet is the best way to get a balanced range of critical nutrients.
Foods that are rich in riboflavin include eggs, liver and meats; fortified cereals and breads; dairy products like milk, yogurt and cheese; and clams, salmon and other fish. Other foods high in riboflavin include almonds and sunflower seeds, beans, spinach, mushrooms and tomatoes. Foods that are rich in one B vitamin often contain many, if not all, of all eight B vitamins.
By ALZinfo.org, The Alzheimer’s Information Site. Reviewed by Eric Schmidt, Ph.D., Fisher Center for Alzheimer’s Research Foundation at The Rockefeller University.
Source: Kishida R, Yamagishi K, Maruyama K, et al: “Dietary intake of folate, vitamin B6, vitamin B12, and riboflavin and the risk of incident dementia.” European Journal of Clinical Nutrition, September 25, 2025.
