Dementia is a medical term that generally covers memory loss, language issues and other thinking abilities that interfere with daily life severely. Categorised by abnormal brain changes, dementia is underpinned by other conditions such as Alzheimer’s disease (when proteins build up in the brain, disrupting nerve cells) or vascular dementia (microscopic bleeding in the brain).

Research shows that certain foods can affect our brains, negatively or positively – and a slower rate of cognitive decline has been noted when certain diets are followed. However, other everyday foods have been associated with a higher risk of developing dementia, in several studies.

Our bodies are affected by the food we eat as our metabolism breaks down what we consume into nutrients and other components. These nutrients go on to aid cells and body systems, including our organs, for physical functions essential for health – but on the other hand, some things we consume can have a detrimental effect on health.

An American non-profit organisation, the Fisher Center for Alzheimer’s Research Foundation, supports research into the causes and treatment of the disease. The organisation reported that a number of ultra-processed foods could lead to an “increased risk” of dementia.

Fried chicken, sausages and pizza were among the food products found to be risky. The study author Huiping Li, of Tianjin Medical University in China, explained that although “ ultra-processed foods are meant to be convenient and tasty” they seem to “diminish the quality of a person’s diet”.

In the study, she explained: “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.

She added: “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.”

Some oven chips, most sugary soda drinks, various packaged breads and crackers, along with breakfast cereals, sweetened yogurts, biscuits, ice cream, ketchup, mayonnaise and canned baked beans are all highly processed. This sort of convenience food tends to make up a large part of a typical diet in the Western world these days – compared to a few decades ago.

Alzheimer’s Disease International (ADI) reports that every year, there are over 10 million new cases of dementia worldwide. On their website, ADI explained that “someone in the world develops dementia every 3 seconds”.

ADI reports: “There are over 55 million people worldwide living with dementia in 2020. This number will almost double every 20 years, reaching 78 million in 2030 and 139 million in 2050. Much of the increase will be in developing countries.”

In their report, the Fisher Center for Alzheimer’s Research Foundation wrote: “People who regularly eat a lot of highly processed foods and drinks like cheeseburgers, chips, fried chicken, sausage, pizza, biscuits and sugary sodas are at increased risk of developing dementia, according to a new report.

“The study found that for every 10 percent increase in daily intake of highly processed foods, the risk of dementia increased by 25 percent. Substituting whole or minimally processed foods for highly processed foods, the study found, led to a lower dementia risk.

“The findings add to growing evidence that what we eat can affect our brain health. Eating highly processed fast foods and other junk foods, numerous studies suggest, increases the chances of developing Alzheimer’s disease, the most common form of dementia overall. Eating a protein-rich, high fiber diet containing lean meats, seafood (not fried), whole fruits and vegetables, and heart-healthy fats like olive oil, on the other hand, may lower dementia risk.”

The study tracked 72,083 men and women (aged 55 or over) from the medical database UK Biobank, for a 10 year period – none had dementia at the start of the research project. Participants who ate the least amount of highly processed foods had the “lowest risk”, but those who ate the most highly processed foods posed higher risk for developing dementia (518 were diagnosed with dementia by the end of the study).

Study author Huiping Li wrote: ““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 percent 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.”