25th February 2014 -- Chemicals present in cooked foods could be linked to Alzheimer’s disease according to a US study in mice.
It found that foods high in compounds called advanced glycation endproducts (AGEs) could contribute to the build-up of beta-amyloid in the brain, a major hallmark of Alzheimer’s disease, the most common cause of dementia. AGEs are found in cooked foods, particularly high fat proteins such as animal meat. They are produced by cooking so are very low in raw fruit and vegetables.
The Alzheimer’s Society shows that 800,000 people in the UK have a form of dementia and more than half have Alzheimer’s disease.
A Channel 5 News and YouGov poll has found that 1 in 5 of us fear developing dementia more than cancer, and two thirds of us are concerned about being diagnosed with dementia in the future.
This new research has uncovered a potential mechanism for how AGEs in the diet might contribute to Alzheimer’s disease. According to the study authors, AGEs suppress SIRT1 – a protein in the body thought to protect against the degeneration of nerves (neurodegeneration).
The researchers found that mice fed a diet low in AGEs boosted their levels of SIRT-1 protein and prevented the accumulation of beta-amyloid in the brain. In contrast, mice fed a diet high in AGEs developed beta-amyloid deposits and showed poor performance in both cognitive and motor tests.
In addition, a small clinical study of healthy humans over the age of 60 found that people who had high AGEs in their blood also had low SIRT1 levels and developed cognitive decline over a 9 month period as well as insulin resistance.
Commenting on the findings, Dr Doug Brown, director of research and development at the Alzheimer’s Society, says: "We are often told that burgers or fried chicken are bad for us and this study is not the first to link the chemicals in some cooked foods to Alzheimer’s. However, this research adds to our understanding of how they might work and makes a strong case for further research.
" Diets with low levels of the compounds show promising effects in mice and should be further explored as a way to prevent dementia through changes in diet. Of course, we must not forget that the majority of research was conducted in mice and the human element of this study is too small to draw any conclusions.
"Evidence suggests that the best way to reduce your risk of developing dementia is regular exercise, not smoking and following a healthy diet."
Dr Simon Ridley, head of research at Alzheimer’s Research UK, says in a press comment: " Diabetes has previously been linked to an increased risk of dementia, and this small study provides some new insight into some of the possible molecular processes that may link the two conditions. Although these findings add to some earlier evidence linking a decrease in the SIRT1 protein to Alzheimer’s, the most common cause of dementia, it’s important to note that the people in this study did not have dementia. This subject has so far not been well-studied in people, and we don’t yet know whether the amount of AGEs in our diet might affect our risk of dementia.
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