A 2014 study looked at tests of 413 Alzheimer's disease drugs and found that more than 99% showed no benefit. In 2017, Eli Lily's Alzheimer's medication failed to mop up plaque as it was expected to do, and Accera's drug — which was supposed to improve how the brain processes sugar and fights off Alzheimer's — proved ineffective.

Just recently, a Food and Drug Administration-approved medication called Aduhelm proved so unhelpful that, generally, insurance companies and Medicare won't pay for it unless it's part of a drug study.

Frankly, the search for a medication that stops or reverses Alzheimer's disease has gotten almost nowhere. 

So while the scientists try to figure out how to fight this complex brain disease, here’s what you can do to reduce your risks:

• Don't eat processed foods. One U.K. study found that for every 10% increase in consumption of ultraprocessed foods, your risk of dementia goes up 25%. Another recent study presented at the Alzheimer's Association International Conference found that adults who ate the most processed food experienced a 25% faster decline in their ability to plan and carry out decisions.

• Maintain a healthy blood pressure. Early research showed older people with high blood pressure are more likely to have biomarkers of Alzheimer's in their spinal fluid, and that the more your blood pressure varies over an eight-year period, the greater your risk of dementia. Recently, Johns Hopkins researchers found that taking potassium-sparing diuretics reduced the risk of Alzheimer's by nearly 75%, and taking other blood pressure medications could lower the risk 33%.