People who consume lots of ultra-processed food may be more at risk of developing dementia, according to a new study.
Food and drink like soft drinks, sugary snacks, ice cream, sausage and flavoured cereal have been linked to a higher risk, while replacing these sorts of food with unprocessed snacks and meals could lower a person’s risk.
Study author Dr Huiping Li, from Tianjin Medical University in China, said: “Ultra-processed foods are meant to be convenient and tasty, but they diminish the quality of a person’s diet.
“These foods may also contain food additives or molecules from packaging or produced during heating, all of which have been shown in other studies to have negative effects on thinking and memory skills. Our research not only found that ultra-processed foods are associated with an increased risk of dementia, it found replacing them with healthy options may decrease dementia risk.”
Researchers looked at data from just over 72,000 people aged 55 or older living in the UK, none of whom had dementia at the beginning of the study. Follow up after an average of 10 years found that 518 people had been diagnosed with dementia.
Over the course of the study, participants answered questionnaires about what they had eaten and drank the day before. Researchers divided the participants into four equal groups of 18,021 depending on the amount of ultra-processed food their daily diet contained.
In the group which consumed the least amount of ultra-processed food, 105 people went on to develop dementia, in comparison to 150 people in the group which ate the most of these types of food.
For those in the lowest category, ultra-processed food formed 9% of their diet, compared to 28% for those who ate the most. The largest food group to contribute to participants’ intake was drinks, then sugary products and dairy products which are ultra-processed.
The research team’s key finding was that for every 10% increase in consumption of ultra-processed food, participants’ risk of developing dementia rose by 25%.
They also found that reducing ultra-processed food by 10% was linked to a 19% reduction in dementia risk.
Ultra-processed food also includes salty snacks, deep-fried chicken, yogurt, canned baked beans and tomatoes, ketchup, mayonnaise, packaged guacamole and hummus, and packaged breads.
Dr Li said: “Our results also show increasing unprocessed or minimally processed foods by only 50 grams a day, which is equivalent to half an apple, a serving of corn, or a bowl of bran cereal, and simultaneously decreasing ultra-processed foods by 50 grams a day, equivalent to a chocolate bar or a serving of fish sticks, is associated with 3% decreased risk of dementia. It’s encouraging to know that small and manageable changes in diet may make a difference in a person’s risk of dementia.”
Dr Maura E. Walker, from Boston University in Massachusetts, wrote an editorial accompanying the study and said: “While nutrition research has started to focus on food processing, the challenge is categorising such foods as unprocessed, minimally processed, processed and ultra-processed.
“For example, foods like soup would be classified differently if canned versus homemade. Plus, the level of processing is not always aligned with diet quality. Plant-based burgers that qualify as high quality may also be ultra-processed. As we aim to understand better the complexities of dietary intake, we must also consider that more high-quality dietary assessments may be required.”
Read the study in full in the journal Neurology.
