Do certain foods cure Alzheimer's disease?

For one thing, large studies have shown that people who eat diets lower in saturated fats, trans fats and cholesterol may have lower rates of dementia overall, so a health diet begets better brain health.
 
The research you may be referring to, though, was a very small study released in 2014. In that study, of 10 patients who were put on a complex program to alter their lifestyle and diet, 9 experienced improvements in memory. That program involved very complex, individualized diets that included eliminating simple carbohydrates and processed foods, adding in regular exercise, methods for stress reduction and improved sleep, and some supplements and hormones.
 
While these results are very exciting to hear, they’re still really early. However, these lifestyle changes are healthy ones that we know would have a good impact on your overall health, so there’s no reason NOT to implement the dietary, exercise, stress and sleep modifications. We just don’t know enough to say that it will absolutely alter dementia, and we definitely cannot say what supplements, or what doses of them, were beneficial.