Updated November 14, 2025 at 11:26 a.m.
A healthy diet, rich in plants such as fruits, vegetables, legumes, whole grains and nuts, could help reduce the risk of cognitive disorders and dementia, according to a team of researchers from Laval University having analyzed the results of around twenty studies on the link between plant-based diet and cognitive health.
This is suggested by a systematic review and meta-analysis of the scientific literature conducted by Catherine Bigras, nutritionist and doctoral student at the Faculty of Pharmacy at Laval University, under the direction of Professor Jean-Philippe Drouin-Chartier and Professor Danielle Laurin, in collaboration with the University of Modena and Reggio Emilia in Italy.
Not all plant-based foods are created equal
The doctoral student specifies that it is not necessary to have an entirely vegetarian or vegan diet to see benefits.
Several studies have assessed the level of adherence to a plant-based diet using an index called Plant-Based Diet Index. The higher the index, that is to say the more plants occupied an important place in the diet, the more the risk of cognitive disorders seemed to decrease.
“This allows us to observe the effects in people who are not necessarily vegetarians, but who consume more plants,” adds Catherine Bigras.
With this systematic review, the doctoral student also observed that the quality of plant-based foods played a central role in cognitive health.
Indeed, when ultra-processed, sugary or refined foods of plant origin, such as white bread or sugary drinks, are very present in the diet, the risk of dementia was higher.
A promising literature review
Despite some variability between studies, the doctoral student observed these links among those that used comparable definitions and measures. “It is the first review to take stock of all the studies that have been published on the subject. We see associations, so it’s worth continuing to dig. »
The cognitive disorders studied included dementia and declines in cognitive performance measured by tests of memory, thinking speed and visual information processing, for example.
As part of her doctorate, she will continue her research on different dietary patterns, often rich in plants, and their association with cognitive disorders. It will use data from a large cohort in which 4,000 people answered around a hundred questions about their diet and completed a cognitive performance test.
Catherine Bigras recalls that a diet rich in plants is already recognized for its positive effects on several chronic diseases. This review suggests that it could also promote better cognitive health.
The signatories of the study, published in Advances in Nutritionare Catherine Bigras, Danielle Laurin and Jean-Philippe Drouin-Chartier, from Laval University, as well as Riccardo Mazzoli, Marcella Malavolti, Giulia Barbolini, Marco Vinceti and Tommaso Filippini, from the University of Modena and Reggio Emilia.
Source : Laval University
(G.Q.)
Download our app
It’s simple and free.
Meta (Facebook and Instagram) blocks your news from Courrier Laval, just as Google continues to obstruct them, in response to Bill C-18.
To access your news and stay connected to the source, Courrier Laval invites you to download its application. You can also subscribe to the weekly newsletter. You will be able to continue reading your news for free, in real time with a lower ratio of advertisements. Don’t forget to turn on notifications and spread the word to your loved ones and contacts!
Apple :
Android :
Newsletter:
