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| Eating wholegrains, fruit and veg and other unprocessed foods lower the chance of dementia.Getty |
From The Age
Regularly snacking on crisps, biscuits and other fatty, sugary foods significantly increases the risk of dementia, a study has shown.
Harvard University found that a diet high in ultra-processed items, which also include ready meals, fizzy drinks, breakfast cereals and cured meats, raised the chance of developing dementia by 58 per cent.
Researchers followed 5000 Americans for 10 years and found those eating the most junk food also had 46 per cent higher risk of developing mild cognitive impairment, the forerunner to dementia.
Processed meats, such as bacon, hot dogs and sliced ham, were found to contribute most to dementia risk.
Prof Cindy Leung, of Harvard’s T.H. Chan School of Public Health, said the study showed that the benefits of switching to healthy foods “extends well beyond our waistline”.
“The good news is we also found the opposite effect for minimally processed food,” she said.
“Those who ate the most minimally processed whole foods, like fruits and vegetables, whole grains, and unprocessed meats, were 41 per cent less likely to develop dementia. [Which means that the junk food eaters have 2.7 times the risk of whole food eaters!]
“This gives us optimism for clear and actionable next steps. Our study shows that eating healthy whole foods is an important behaviour that can protect our minds as we age.”
Although researchers said they could not prove that junk food was driving dementia they added that it was “biologically plausible” and fitted with growing scientific evidence that ultra-processed foods impact brain function.
Dr Alex Henney, an endocrinologist at the University of Liverpool, said that junk foods may drive obesity, Type 2 diabetes and cardiovascular disease, all of which raise the risk of dementia.
Additives such as emulsifiers and preservatives may also drive inflammation, which has also been implicated in dementia.
The study was published in a special issue of The American Journal of Public Health, looking into the harms of ultra-processed foods.
Experts warned that the public was being prevented from making healthy choices because of “aggressive marketing and harmful food environments”.
New research published in the issue found that the ingredients in ultra-processed food were often combined in forms deliberately chosen to engage the brain’s reward systems, making them likely to trigger addictive patterns of eating.
Dr Ashley Gearhardt, professor of psychology, of the University of Michigan, found that quick-release carbs coupled with high fat created the “once you pop, you can’t stop” addictive quality of junk food.
“Real whole food did not trigger an addictive response,” she said. “Nobody is bingeing on that stuff. Nobody is saying ‘apple slices, bet you can’t stop once you start.’
“The number one lever that was pulled was rapidly delivering carbohydrates into the body. That was often complemented by fat.
“This is literally missing from Mother Nature. Our bodies never evolved to get this ‘one-two punch’ in these energy-dense concentrated packages.”
Researchers argued that many of the same corporate strategies used by the tobacco industry were now being employed to keep people addicted to disease-causing food.
They found that many US tobacco companies had bought into the ultra-processed food industry and were using sales tactics similar to those used for cigarettes to sell the products, such as flavour engineering, and creating seemingly “low-fat” versions to retain customers who were concerned about health harms.
“Ultra-processed food is not simply an issue of personal responsibility or individual choice,” said Dr Nicholas Chartres, the lead editorial author and researcher at the University of Sydney and the University of California, San Francisco.
“The evidence increasingly points to a commercial system that has engineered, marketed, and normalised products linked to widespread chronic disease. The public health and government response must reflect that reality.
“The research that has been published adds to a growing body of evidence that these products are associated with chronic disease and that they have addictive characteristics.”
