Too Much Saturated Fat Tied to Alzheimer's Risk?
Researchers say a small, new study shows that fat cut the body's level of a chemical that keeps Alzheimer's at bay
"Diet can really change levels of these toxic proteins and of these mediators that help clear these amyloids," Craft said. "Diets that are very high in bad cholesterol seem to interfere with ApoE's ability to clear amyloid."
One gerontology expert, who wrote an editorial accompanying the study in the journal, didn't think the link was quite that clear.
Although the study shows that diet can affect brain chemistry, it does not definitely tie diet to a person's risk for Alzheimer's disease, said Dr. Deborah Blacker, director of the Gerontology Research Unit at Massachusetts General Hospital in Boston.
"Is it plausible to say this could affect the risk of having Alzheimer's pathology in your brain? It's not showing that," said Blacker, who also is with the Harvard School of Public Health. "It's showing that some of the chemicals related to Alzheimer's pathology can shift in response to dietary factors."
The study does, however, offer important insight into the value of good nutrition, she said.
"The important lesson from the study is that dietary intervention can change brain amyloid chemistry in largely consistent and apparently meaningful ways, in a short period of time," Blacker wrote in the editorial. "Does this change clinical practice for those advising patients who want to avoid dementia? Probably not, but it adds another small piece to the growing evidence that taking good care of your heart is probably good for your brain too."
People focus on diet in terms of weight and heart health, but they overlook that nutrition can be key to cognitive function as well, Craft said.
"Diet is a very underappreciated factor in terms of brain function," she said. "It's quite well accepted for your heart and your cholesterol and your blood, but diet is critical for a healthy brain aging. Many of the things the brain needs to function properly -- fatty acids, certain amino acids -- come only from food."