Linking Alzheimer's to insulin is a new one to me - I've heard about plaque on the brain and toxic proteins called beta amyloid…the question around all of these is still whether they're a symptom or a cause.
To simplify the path to a cure: they've found the genetic predisposition towards Alzheimer's and dementia, step two will be narrowing down the epigenetic markers that trigger the condition, and step three will be preventing the condition being triggered in the first place. I predict within 10 years we'll have a pill. (I hope! I spend a lot of time in a high care nursing home visiting a much loved family member, and the cost of this devastating disease affects not just the afflicted, but family members and society as a whole as our population ages and resources are stretched).
The Alzheimer's link is a relatively new one (at least in the media) and looks to be a little bit of sensationalism: it sounds scary, makes for a good story and there's plenty of ways to angle it.
Pragmatically, there's little downside to publishing it as well - if people eat healthier and exercise a little more as a result, brilliant. For researchers given the wide base of ground to cover in the disease, if it gives more funding in their fields, also brilliant.
Taking a step back and looking at Alzheimer's just as a metabolic disease (which does have some merit, let me find the papers) does give some new avenues to explore. Same as you will be interested to see what comes out of it. It truly is a crushing disease for all involved.