[wtd]

Quote: "... analysed medical records from 1,958,191 people aged 55, on average, for up to two decades."

Obesity presents a documented risk to longevity...so the noted age 55 is somewhat early for dementia onset...

[Vermont Lt]

I think the average start time was 55 years. It took them to 75. You are correct in your assumption that obese people probably die from heart disease and other things before getting to an age of dementia.

The study would have to adjust for that.

[fatnotlazy]

I understand that there are several types of dementia, including at least one described as “early onset.” Can start in the 30s.

[Chickensoup]

...so the noted age 55 is somewhat early for dementia onset...

____________

Actually not so early. We see a fair amount of dementia in the 50s and 60s.