In a recent JAMA Neurology study, researchers report that consuming ultra-processed foods (UPFs) increases the chance of cognitive decline, particularly amongst middle-aged adults.

Study: Association Between Consumption of Ultra-processed Foods and Cognitive Decline. Image Credit: Ekaterina Markelova / Shutterstock.com

What aspects contribute to dementia?

In 2019, dementia was estimated to affect about 57 million worldwide, with 153 million cases expected by 2050 resulting from the worldwide rise in life expectancy. Despite being one of the crucial significant causes of disability in high-income countries, there stays a scarcity of effective treatments for stopping or delaying the event of dementia symptoms.

Nevertheless, lifestyle habits corresponding to regular physical activity, a healthy eating regimen, and never smoking appear to scale back the likelihood of developing dementia. Particularly, the every day consumption of whole grains, vegetables, fruits, nuts, and fish has been linked to increased brain volume and the retention of cognitive function over time.

The health impacts of UPFs

UPFs, that are food products that consist of highly processed food components corresponding to oils, fats, sugars, starch, and protein isolates, offer little to no health profit for the buyer. Along with these ingredients, UPFs also often consist of artificial flavorings, colorings, emulsifiers, and other cosmetic additives. Some examples of common UPFs include breakfast cereals, sweet and savory snacks, ice cream, ready-to-eat frozen meals, processed meats, and sugar-sweetened beverages.

Over the past 40 years, the production of UPFs by the worldwide food industry has increased substantially. The truth is, recent estimates indicate that UPFs comprise 58% of the calories consumed by U.S. residents, 57% of those consumed by British residents, 48% of those consumed by Canadian residents, and 30% of calories consumed by Brazilian residents.

Previous studies indicate widespread consumption of UPFs is directly related to an increased risk of cardiovascular diseases, metabolic syndrome, and obesity. Nonetheless, resulting from the shortage of knowledge correlating the chance of UPF consumption and dementia, the present study aimed to higher understand this potential association.

In regards to the study

In the present multicenter, prospective cohort study, individuals between the ages of 35 and 74 were recruited from six different cities throughout Brazil, including Belo Horizonte, Porto Alegre, Rio de Janeiro, Salvador, São Paolo, and Vitoria. Data from the study participants were collected in three waves roughly 4 years apart, starting in 2008 and ending in 2019.

At baseline, the study participants provided information on the frequency to which they consumed different foods and drinks products every day. These food products were classified in keeping with the extent of their industrial processing.

Group 1 food products, for instance, included unprocessed or minimally processed foods corresponding to fresh, dry, or frozen vegetables and fruit, grains, meat, and milk. Group 2 food products included processed cooking ingredients corresponding to salt, sugar, and oils.

Group 3 consisted of processed foods corresponding to canned fruits, salted, smoked, or cured meat or fish, in addition to certain bread and cheese products. Group 4 consisted of UPFs corresponding to flavors, sweeteners, and emulsifiers.

The study participants also underwent cognitive assessments as much as thrice every 4 years. These assessments included memory tests corresponding to immediate and late recall, in addition to recognition glossary tests. Semantic and phonemic verbal fluency tests were also included to evaluate the participants’ executive function abilities.

High UPF consumption related to cognitive decline

A complete of 10,775 participants were included within the study, with a mean follow-up period of eight years. At baseline, the mean age of the study participants was about 52 years old, almost 55% of whom were female, 53% were White, and 57% had a school degree. Moreover, the mean body mass index (BMI) of the study participants at baseline was about 27, with a mean total every day calorie intake of two,856 kcal.

The every day eating regimen of participants that comprised greater than 19.9% UPFs experienced a 28% faster rate of world cognitive decline. More specifically, these individuals experienced a 25% faster rate of executive function decline, with no significant change observed in regard to their memory function.

Notably, study participants who were younger than 60 years were more more likely to experience global cognitive decline as in comparison with those aged 60 years or older who consumed similarly high levels of UPFs of their every day eating regimen.

The researchers hypothesize that this decline in executive function might be resulting from cerebrovascular lesions attributable to the chronic consumption of UPFs. UPF consumption may increase the circulation of proinflammatory aspects that subsequently result in systemic inflammation that affects the brain.

Taken together, the study findings obtained from a big population cohort emphasize the importance of limiting UPF consumption, particularly in middle-aged adults, to preserve cognitive integrity.

Journal reference:

• Goncalves, N. G., Ferreira, N. V., Khandpur, N., et al. (2022). Association Between Consumption of Ultra-processed Foods and Cognitive Decline. JAMA Neurology. doi:10.1001/jamaneurol.2022.4397.