While most of us are familiar with type 1 and type 2 diabetes, you may not have come across the term ‘type 3 diabetes’ before. First things first, this is not to be confused with type 3c diabetes, which is something else entirely. It is, however, related to insulin resistance in the brain.

Being diagnosed as insulin resistant generally means that someone is either prediabetic or has type 2 diabetes. But scientists have proposed that it can also result in the brain’s neurons lacking glucose, which is needed for proper function, and this can lead to symptoms of Alzheimer's disease.

While type 3 diabetes is not an officially recognized health condition, in 2008 Dr Suzanne de la Monte and Dr Jack Wands of Brown University put forward a proposal that Alzheimer’s disease could be termed ‘type 3 diabetes’ due to its strong links with insulin resistance in the Journal of Diabetes Science and Technology. Insulin resistance may be a leading cause of dementia, as this glucose metabolism deficiency in the brain contributes to symptoms such as loss of memory, decrease in judgment and reasoning skills.