Dementia risk linked to how food is cooked

Over-cooking and blackening food leads to a number of chemical changes in the food. For the first time, scientists have linked some of these chemical byproducts to the rise in age-related dementia risk.

Whenever food is cooked, there are always some degree of chemical changes occurring. Many of these changes are positive as they add to the flavour and appearance of food and even the bioavailability of some nutrients. But there is one chemical change that has scientists looking more closely for potential links with disease.

Named advanced glycation end-products (AGEs), this class of food chemicals arise naturally when food is heated to the point of browning or charring. Called the Maillard reaction, it is caused by a reaction between sugars and amino acids in proteins. It is what gives roasted food its distinctive flavour and aroma, and bread its brown crust.

Dementia risk and AGEs

AGEs are not entirely benign chemicals and accumulation of them in the body can promote oxidative stress and inflammation. Researchers are now even linking AGEs to part of the development of insulin resistance and type 2 diabetes.

Extending the work already done on AGEs in both animal and human studies, researchers have now explored if their inflammatory manner of action could also be an important part in the process of dementia development.

Mice who were raised on a diet high in AGEs were much more likely to develop symptoms consistent with dementia compared to mice fed a low AGE diet. Mice on the high AGE diet showed increased amounts of amyloid beta proteins in their brains. These proteins are the sticky substances that can form plaques in the brains of people with Alzheimer’s disease.

Taking the research outside of the mice cage, the researchers next monitored the blood levels of AGEs in 93 adults aged over 60 years of age for a period of 9 months. Even over this short time period, those people who had more AGEs in their blood experienced greater cognitive decline as well as reduced insulin sensitivity compared to those with low AGE levels.

What it all means

The research into AGEs and inflammatory diseases is still at an early stage, but the findings from both animal and human studies are certainly encouraging scientists to dig deeper. Any research on lowering dementia risk is positive to see. The good news here is that a low AGE diet is very much in line with healthy eating guidelines: higher amounts of fruits and vegetables and minimally processed foods, and less overly processed foods, especially baked and fried foods. And when cooking, opt for shorter heating times, use lower temperatures and a high moisture content and avoid over browning or charring food.