Study shows people ‘right size’ portions of high-calorie foods

New research has revealed that humans moderate the size of the energy-rich meals they eat, suggesting that people eat more intelligently than previously thought.

The findings, led by the University of Bristol, revise the long-standing belief that humans are insensitive to the energy content of the food they eat and are therefore likely to eat the same amount of food (by weight) regardless of whether it is rich or poor in energy.

The study, published today in The American Journal of Clinical Nutrition, is especially significant as it challenges the common view among researchers that people tend to overeat high-energy foods.

This idea stems from previous studies that manipulated the energy content of foods or meals to create high- and low-energy versions. In those studies, people weren’t told whether they were eating a low- or high-energy version, and the findings showed they tended to eat meals of the same weight, resulting in higher calorie intake with the high-energy version .

“For years, we have believed that humans overeat energy-dense foods without thinking. Surprisingly, this study indicates a degree of nutritional intelligence by which humans manage to adjust the amount they consume of energy-dense options,” he said. lead author Annika Flynn, Ph.D. Researcher in Nutrition and Behavior at the University of Bristol.

Instead of artificially manipulating calories in individual foods, this study looked at data from a Test using a normal, everyday meal with different energy densities, such as a chicken salad sandwich with fig muffins or blueberry almond porridge. The trial involved 20 healthy adults who temporarily lived in a hospital ward where they were served a variety of meals for four weeks.

The team of international researchers, including leading diet and metabolism experts from the US National Institutes of Health (NIH), calculated the calories, grams, and energy density (calories per gram) of each meal consumed by each participant . The results demonstrated that meal calorie intake increased with energy density in energy-poor meals, as was also found in previous observations with artificially manipulated foods. Surprisingly, however, with increased energy density, a tipping point was observed where people begin to respond to increases in calories by reducing the size of the meals they eat. This suggests a previously unrecognized sensitivity to the energy content of the foods people ate.

As this finding was based on data from a small, highly controlled trial, the researchers went on to see if this pattern held when the participants lived freely, choosing their own meals. Using data from the UK National Diet and Nutrition Survey, the researchers again found that calorie intake from meals increased with energy density on foods that were low in energy and then decreased on foods that were high in energy. Importantly, for this tipping point pattern to occur, participants would have needed to consume smaller meals, by weight, of the higher energy meals.

Annika said: “For example, people ate smaller portions of a pasta dish with cream cheese, which is a high-energy meal, than a salad with lots of different vegetables, which is relatively low in energy.”

This research sheds new light on human eating behavior, specifically an apparent subtle sensitivity to calories in energy-dense foods. foods.

Co-author Jeff Brunstrom, Professor of Experimental Psychology, said: “This research lends further weight to the idea that humans are not passive eaters after all, but instead display the discerning ability to moderate the amount of an energy-rich meal. they consume”.

“This work is particularly exciting as it reveals a hidden complexity of how humans interact with modern Energy-rich foods, something we have been referring to as ‘nutritional intelligence’. What this tells us is that we don’t seem to passively overeat these foods, so the reason they’re associated with obesity is more nuanced than previously thought. For now, at least this offers a new perspective on a long-standing topic and opens the door to a number of important new questions and avenues for future research.”