When it comes to eating your way to a healthier brain as you age, it’s time to go nuts for the nuts and mental for the lentils!
New research suggests not only that eating greater amounts of red and especially processed meat increases the risk of developing dementia, but that replacing these harmful animal products with natural healthy alternatives such as pulses, legumes and nuts could swing the pendulum the other way, actively cutting that risk by as much as a fifth (20 per cent).
The report from Massachussets – carried out by the Harvard TH Chan School of Public Health, the Massachussets Institute of Technology (MIT) Broad Institute and the Mass General Brigham healthcare system – found that eating 85g of red or processed meat a day increased the risk of developing dementia by 13 per cent. That’s just two rashers of bacon or one sausage.
Looking at study participants’ own perception of their cognitive decline, the scientists found those who ate one or more servings of red meat daily were at a 16 per cent higher risk of developing dementia than those who ate little or no meat. The risk figure was still 14 per cent for those who ate moderate amounts. Data on 133,771 individuals with an average age of 49 was used for the study. They were followed for up to 43 years, during which time 11,173 were diagnosed with dementia.
Research has previously suggested that just 25g of processed meat a day can increase your dementia risk by 44 per cent, and that adopting a plant-based lifestyle can slow the progress of Alzheimer’s for those in the early stages of the disease.
So it’s clear from the findings not only that eating less red and processed meat is of benefit to your brain, but that you can boost that benefit still further by tucking into more nutritious and planet-friendly plant-based sources of protein.
“Dietary guidelines tend to focus on reducing risks of chronic conditions like heart disease and diabetes, while cognitive health is less frequently discussed, despite being linked to these diseases,” said Daniel Wang, one of the authors of the study, which is published in the journal Neurology. “We hope our results encourage greater consideration of the connection between diet and brain health.”
A compound created in the gut when meat is broken down could explain the link with dementia because it leads to the accumulation in the brain of two damaging proteins. Trimethylamine N-oxide (TMAO) “may increase cognitive dysfunction due to its effects on the aggregation of amyloid and tau, proteins involved in Alzheimer’s disease”, the report said, though saturated fat and salt can also harm brain cells.
And why are nuts, lentils and legumes the solution? Because of the power of prebiotics, which improve the balance of microflora in the gut. A healthy range of gut bacteria, fostered by the prebiotic fibres in healthy wholefoods, keeps a lid on the creation of TMAO.