What influence do plant-based meals have on mood and the feeling of satiety compared to animal-based meals? Neuroscientists from the MPI CBS have investigated this in three smartphone-based studies in over 400 canteens in Germany and their results are now in the journal Nature Science of Food published.
Recent studies show that by doing without animal products such as meat and milk, agricultural climate emissions can be reduced by 80 percent. However, the physiological and psychological factors involved in the consumption of plant-based foods are largely unclear. What actually happens in our body after a plant-based meal compared to an animal-based meal? And who is most likely to choose which dish in the canteen? “Because fiber is associated with improved signaling between the gut and the brain, we hypothesized that a plant-based meal would induce greater satiety and mood compared to an animal-based meal,” says Evelyn Medawar, who works at the Max -Planck Institute for Human Cognitive and Brain Sciences in Leipzig researches nutrition and eating decisions.
16,300 people in 400 canteens
A total of more than 16,300 adults in over 400 canteens across Germany took part in three large-scale smartphone-based studies. With the help of the iMensa app, the participants not only rated the dishes, but also voted on their mood and hunger before and after the meal using emojis.
The results show that – as expected – eating a meal generally led to satiety and better mood – albeit regardless of whether it was vegetarian, vegan or with meat. “People who chose a plant-based meal reported slightly better mood before and a smaller increase in mood after the meal compared to those who chose an animal-based meal,” explains Medawar.
“Protein content also affected post-meal satiety, albeit modestly, while gender and taste rating had a strong impact on satiety and mood in general.” Overall, more women and various people consumed plant-based dishes.
With very badly rated dishes, the hunger after the meal increased and the mood dropped significantly. On the other hand, when the dishes were rated as very tasty, hunger decreased significantly and mood increased moderately. In addition, plant-based dishes were more often consumed alone and not in company, which could also have led to a lack of mood enhancement through social exchange.
Many want to eat vegan
“Overall, however, we could not find any profound effects of plant-based versus animal-based meals on satiety and mood,” sums up Evelyn Medawar. The study data showed that of the dishes chosen in the canteen, 55 percent contained animal ingredients and 45 percent were vegetarian or vegan. The demand for plant-based dishes in German canteens is therefore very high. However, the palatability and protein content of plant-based dishes should be further improved.