While obesity is correlated with a host of health problems (cardiovascular, damage to joints, increased risk for diabetes), this April, 2015 study published in The Lancet shows that it may protect against dementia.

Different results than we had previously thought to be true…. now the next step is to figure out why weight plays such a role in the development of dementia?

Compared with people of a healthy weight, underweight people (BMI <20) had a 34% higher risk of dementia. Furthermore, the incidence of dementia continued to fall for every increasing BMI category, with very obese people (BMI >40) having a 29% lower dementia risk than people of a healthy weight.

You can read more about this in an article by The Guardian, which states:

Many other studies have shown an association between obesity and an increased risk of dementia. These findings demonstrate the complexity of research into risk factors for dementia and it is important to note that BMI is a crude measure – not necessarily an indicator of health. It’s also not clear whether other factors could have affected these results.

Or from The Telegraph, which includes:

Dr Liz Coulthard, Consultant Senior Lecturer in Dementia Neurology, University of Bristol, added: “We do know that obesity carries many other risks including high blood pressure, heart disease, diabetes and increased rates of some types of cancer. So maintaining a healthy weight is recommended.”