Changing Your Diet Can Protect Against Alzheimer's Disease, Study Shows

The public discourse on food seems to revolve around what will or won't make you fat. But food choices affect more than just weight — a new study shows that changing your diet can help prevent Alzheimer's disease. In the study, scientists changed the diets of mice who were bread to have Alzheimer's, and results demonstrated that this could slow the progression of the disease and reverse memory loss.

In the past decade or so, researchers have shifted from focusing exclusively on curing Alzheimer's disease towards finding ways to prevent and treat it. Some of the most promising developments have been dietary. There's substantial evidence that omega-3 fatty acids — the main component of fish oil — have a protective effect against Alzheimer's and dementia. And mounting evidence suggests that sugar has a brain damaging effect (some researchers have even suggested calling Alzheimer's "type 3 diabetes")

This is important because unlike, say, the flu, Alzheimer's disease doesn't strike all at once. In fact, scientists have recently discovered that the brain processes leading up to full-blown Alzheimer's can take decades to develop. Theoretically, this leaves a lot of time to intervene with smart lifestyle choices (some patients who have done so have been able to see some remarkable results).

In this new study, published in the Journal of Nutritional Biochemistry , researchers looked at female mice carrying genetic mutations linked to Alzheimer's disease. From five through 13 months olds, the mice were fed one of four different diets. Some mice were on a diet with fat content very similar to the standard Western diet. Other mice got a diet with similar total fat content but a higher proportion of omega-3 fatty acids. Some of the high-omega-3 diet mice also got a mix called Fortasyn, which contained folic acid, vitamin E, selenium, Choline, and other nutrients; others got an extra dose of plant sterols. A control group of wild mice without mutations were fed the standard diet.

When given tests of spatial and smell memory, mice with Alzheimer's mutations and the standard diet did significantly worse than the control mice. But Alzheimer's mice on the experimental diets diet just as well as control mice on the odor recognition test, and mice on the omega-3/Fortasyn mix diet did just as well on the spatial test, too. At the end of study, mice in the plant sterol group also had significantly less build-up of amyloid-β, a protein in the brain that becomes overabundant in Alzheimer's patients.

That the different experimental diets yielded different positive effects illustrates that there's no magic bullet approach to preventing Alzheimer's (hence the mixed results of studies measuring only one nutrient or other in isolation). But, taken together, a healthy diet could go a long way to keeping your mind healthy as you age.