The Science Media Centre - an independent 'press office for science' - issues frequent research roundups to put new scientific, medical and health research into context. The SMC's roundups help busy journalists critically analyse the strengths and weaknesses of new research.
Professor Tom Dening, Director of the IMH Centre for Dementia, was one of six experts who recently provided the SMC with a response to a paper on diet, diabetes and dementia which was published in Proceedings of the National Academy of Sciences (PNAS). The story has already been picked up by The Guardian. Professor Dening's response follows:
"We already know that increasing chronological age makes you more at risk of developing dementia, but how about AGE, with capitals? Advanced glycation end products (or AGEs) are proteins or fats that become modified after contact with sugars. They have various unpleasant effects, for example contributing to the risk of vascular complications of diabetes. Scientists have speculated since the 1990s that AGEs may be important in Alzheimer's disease, which is the most important cause of dementia.
"This paper adds to the picture. Mice were fed diets with varying levels of a particular AGE, called MG. Those who received higher amounts showed biochemical and brain changes, including higher levels of amyloid (the characteristic marker of Alzheimer's disease) in their brains. They also showed impairments of learning and memory. Alongside this work, the research team also tested 93 healthy New York volunteers over 9 months and found that their MG levels was related to more AGE in their diet and that higher MG led to more cognitive decline during the period studied.
"Should we worry about our diet? Yes, there is already plenty of evidence to support healthy eating. Does this paper make us more worried? A bit. Foods high in protein and fat, such as meat, cheese, and egg yolk, are rich in AGEs, and cooking at high temperatures, e.g. frying and barbecues, increases AGEs. Dietary restriction of AGEs can bring about significant reductions. What isn't yet clear is how much these effects contribute to Alzheimer's disease compared to other factors, and we don't know whether dietary restriction of AGEs would be helpful in prevention. The difficulty will be in the length of the research projects you'd have to run in order to show significant effects. In the meantime, crunch those carrots and reach for the brown rice."
The Science Media Centre is an independent organisation working to promote the voices, stories and views from the scientific community to the news media when science is in the headlines. Over 80 supporters including scientific institutions, media groups, charities, universities, corporate organisations and individuals fund the Centre, including the Institute of Mental Health.