People who avoid UPFs consume fewer calories despite eating more, study finds

People who avoid ultra-processed foods (UPFs) consume 330 fewer calories a day on average despite eating more, a small study suggests.

When food is presented in its natural state, people tend to make “much smarter decisions”, according to researchers.

For the study, experts from the University of Bristol reanalysed data from a US clinical trial including 20 people, which concluded that eating UPFs exclusively leads to excessive calorie consumption and weight gain.

They found that people eating solely wholefoods chose to load up on fruits and vegetables over higher calorie options such as pasta and cream.

According to the study, people avoiding UPFs ate 57% more when food was measured by weight.

Jeff Brunstrom, a professor of experimental psychology at the University of Bristol, said: “It’s exciting to see when people are offered unprocessed options they intuitively select foods that balance enjoyment, nutrition, and a sense of fullness, while still reducing overall energy intake.

“Our dietary choices aren’t random – in fact we seem to make much smarter decisions than previously assumed, when foods are presented in their natural state.”

The study, published in the American Journal of Clinical Nutrition, also suggests that some UPFs met micronutrient requirements through vitamin fortification.

Researchers found pancakes and French toast sticks contained vitamin A.

However, people eating exclusively wholefoods got vitamin A from carrots and spinach, which are much lower in calories.

Dr Annika Flynn, senior research associate at the University of Bristol, said: “This raises the alarming possibility that UPFs deliver both high energy and micronutrients in one hit, which could result in calorie overload, because they effectively kill the beneficial trade-off between calories and micronutrients.

“Conversely, this healthy competition is promoted by wholefoods and therefore encourages people eating them to favour micronutrient powerhouses, such as fruit and veggies, over high-energy options like pasta and meat.”

Prof Brunstrom added: “Overeating is not necessarily the core problem.

“Indeed, our research clearly demonstrated consumers on a wholefood diet actually ate far more than those on a processed food one.

“But the nutritional make-up of food is influencing choices and it seems that UPFs are nudging people towards higher calorie options, which even in much lower quantities are likely to result in excess energy intake and in turn fuel obesity.”