The Link Between Sugar and Alzheimer

A high-carb diet, and the attendant high blood sugar, are associated with cognitive decline.

In recent years, Alzheimer’s disease has occasionally been referred to as “type 3” diabetes, though that moniker doesn’t make much sense. After all, though they share a problem with insulin, type 1 diabetes is an autoimmune disease, and type 2 diabetes is a chronic disease caused by diet. Instead of another type of diabetes, it’s increasingly looking like Alzheimer’s is another potential side effect of a sugary, Western-style diet.

In some cases, the path from sugar to Alzheimer’s leads through type 2 diabetes, but as a new study and others show, that’s not always the case.

A longitudinal study, published Thursday in the journal Diabetologia, followed 5,189 people over 10 years and found that people with high blood sugar had a faster rate of cognitive decline than those with normal blood sugar—whether or not their blood-sugar level technically made them diabetic. In other words, the higher the blood sugar, the faster the cognitive decline.

 “Dementia is one of the most prevalent psychiatric conditions strongly associated with poor quality of later life,” said the lead author, Wuxiang Xie at Imperial College London, via email. “Currently, dementia is not curable, which makes it very important to study risk factors.”