A new study shows that many of the lifestyle changes being recommended by doctors may not prevent Alzheimer's disease. Time.com reported on a study by the National Institute of Health (NIH) that was commissioned to conduct an analysis of 165 papers on the subject between 1984 and 2009. Previous to this study, many doctors were encouraging patients to implement lifestyle changes such as the Mediterranean Diet and maintaining cognitive function by learning new things and engaging in mental stimulation (sometimes via crossword puzzles). The review did show that these preventative behaviors are linked to a lower risk of Alzheimer's, however, the link was much weaker than it was previously believed.
The review did offer some reassurance about risk factors that cause cognitive decline, showing links between an increased risk of developing Alzheimer's and smoking, diabetes, metabolic syndrome, depression, and genetic factors. The problem is, none of the links were strong enough to justify the current practice of encouraging patients to make certain lifestyle changes to prevent the onset of Alzheimer's. However, it is likely that doctors will continue to encourage these changes, as they do lead to a generally healthier lifestyle in general. The Alzheimer's Association has stated that it will continue to support doctors who recommend these changes, as the weak link still offers evidence that they may be heading in the right direction towards prevention of dementia.
I think that even though this review of past studies on the subject hasn't shown a significant link between positive lifestyle changes and Alzheimer's prevention, it is still beneficial to patients if their doctors recommend they make these lifestyle changes. A diet high in omega-3 fatty acids, unsaturated fats, and fruits and vegetables is a healthier diet, which leads to a healthier individual. Continuing to develop cognitively can lead one to have a more intellectually satisfying life. Maintaining social relationships wards off depression. All of these changes still encourage a healthy lifestyle, and I think that maintaining one's psychological and physiological well-being is certainly something that all doctors should be encouraging their patients to do. Maybe it won't fight off Alzheimer's or other forms of dementia, but the evidence does exist that a healthy, happy lifestyle leads to a richer, higher quality life experience.