
Disentangling the specific effects of individual foods on the human body is difficult, in part because maintaining strict control over people’s diets to study them over long periods of time is problematic. Moreover, randomized controlled trials, the most reliable type of study for establishing causality, are expensive to carry out.
So far, most nutritional studies, including these two, have only shown correlations between ultraprocessed food consumption and health. But they cannot rule out other lifestyle factors such as exercise, education, socioeconomic status, social connections, stress, and many more variables that may influence cognitive function.
This is where lab-based studies using animals are incredibly useful. Rats show a cognitive decline in old age that parallels humans. It’s easy to control rodent diets and activity levels in a laboratory. And rats go from middle to old age within months, which shortens study times.
Lab-based studies in animals will make it possible to determine if ultraprocessed foods are playing a key role in the development of cognitive impairments and dementia in people. As the world’s population ages and the number of older adults with dementia increases, this knowledge cannot come soon enough.
