Thanks for your feedback, this will help us improve our content for you!
AAIC 2022 | High intake of ultra-processed food associated with cognitive decline
Natalia Gonçalves, PhD, University of São Paulo Medical School, São Paulo, Brazil, shares the findings of a prospective study assessing the longitudinal association between the consumption of ultra-processed foods (UPF) and cognitive decline. Study participants were enrolled from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) and followed up for 9 years. Food frequency questionnaires were used to assess UPF consumption as a percentage of total daily calorie intake. In the overall study population of more than 8000 individuals, 28% of daily calorie intake came from UPF on average. Compared to consumption in the first quintile, highest UPF intake was related to decline in executive function and memory performance. Dr Gonçalves comments on the importance of the findings for emphasizing the impact of a healthy lifestyle for brain performance. This interview took place at the Alzheimer’s Association International Conference (AAIC) 2022 in San Diego, CA.
Transcript (edited for clarity)
We partnered with a very special group in Brazil from Professor Carlos Monteiro who created the NOVA classification for ultra-processed foods, and they helped us create the classification for our work. After that, what we did is we took data from previous collection of data from the ELSA-Brazil study, which is a study that accompanies public servants from six cities in Brazil, and we analyzed this data and the correlation of ultra-processed foods consumption and cognition...
We partnered with a very special group in Brazil from Professor Carlos Monteiro who created the NOVA classification for ultra-processed foods, and they helped us create the classification for our work. After that, what we did is we took data from previous collection of data from the ELSA-Brazil study, which is a study that accompanies public servants from six cities in Brazil, and we analyzed this data and the correlation of ultra-processed foods consumption and cognition.
Ultra-processed foods are those foods that go through industrial processing. We don’t classify the cooking methods as processing in the NOVA Classification, so it’s industrial process. Those foods that have emulsifiers, colorings, preservatives are considered ultra-processed foods. For example, frozen foods, frozen pizza, frozen lasagna, ready made snacks like chips, like chocolates, hot dogs. All of these types of foods are ultra-processed and foods that we eat that are close to their natural state are not processed or minimally processed foods. So we have rice, beans that are not canned. We also have vegetables, fruits, milk, meat are not ultra-processed foods. We also have those foods that are processed, but not ultra-processed, that are foods that are generally added only salt. So we have canned foods. Cheese for example, is processed foods, but not ultra-processed foods.
What we did find was that in this sample study, people consumed on average 27% of daily calories from ultra-processed foods, and those who consumed more than 20% of daily calories from ultra-processed foods had a faster cognitive decline in the executive function and the global cognition. For the executive function it was a 25% faster decline, and for the global cognition it was a 28% faster decline.
Our population is very mixed and we think our data can be generalized to other populations. I think that for those populations who eat more than that, more than 20% of daily calories from ultra-processed foods, probably we will find a faster decline than in our population. But there are many populations who it a lot less than that and it would be interesting to see if there is actually a correlation of ultra-processed food consumption and cognitive decline in those populations as well.
We didn’t have imaging studies here on the ELSA-Brazil study, so we only have hypotheses. What we see on the literature is that people who consume a Western diet have less brain volume, they also have a loss in white matter and sometimes in gray matter as well. We also hypothesize that, especially for the executive function, there might be some type of microvascular lesions that can lead to the executive function decline. We also see that people who consume a Western diet have chronic inflammation, and that might be also a process related to the cognitive decline. But these are all hypothesis, we need further studies to confirm that what hypothesis is actually true.