New Research on Dieting and Wholefoods
When we think of dieting, it often revolves around smaller portions or fasting. But, interestingly, recent research suggests there’s a different approach. It seems possible to maintain regular meal sizes—or even indulge a bit—while still significantly reducing caloric intake.
The trick is to focus on whole, unprocessed foods, like fruits and vegetables, instead of the ultra-processed foods (UPFs) that are prevalent in many diets today. This study indicates that a more natural eating approach might help us avoid consuming excessive calories, even when eating freely.
Conducted by researchers from the University of Bristol in the UK, this study revisited data from a 2019 clinical trial that primarily looked at the extra energy consumption of individuals eating UPFs.
During that month-long trial, 20 participants had the freedom to eat as much as they wanted from two randomly assigned diets, either unprocessed or ultraprocessed, which they switched halfway through.
The findings were noteworthy: when given unprocessed wholefoods, participants consumed over 50% more food than those on UPF diets but averaged 330 fewer calories each day.
Researchers aimed to investigate the food choices made within each diet and how those choices impacted overall energy intake.
According to psychologist Jeff Brunstrom from the University of Bristol, the results are encouraging. “When offered unprocessed options, people seem to instinctively choose foods that offer a balance of enjoyment, nutrition, and fullness, which ultimately helps reduce overall energy intake,” he commented.
Interestingly, the previous diet trial emphasized that participants had the ability to curate their meals, suggesting an inherent ‘nutritional intelligence.’ This intuitive eating ability might get disrupted when ultra-processed foods dominate. They tend to alter our perception of what’s nutritious.
The concept here is that when consuming food in its natural, unprocessed form, we tend to prefer micronutrient-rich options, like fruits and veggies. Some studies imply that our bodies may instinctively seek to balance the caloric intake from fats and carbohydrates with necessary vitamins and minerals.
However, with UPFs, this ability seems to be less effective, as these foods are often loaded with calories and artificially fortified with nutrients. Thus, we might end up consuming more calories without feeling the need to eat as much.
“This raises serious concerns that UPFs might provide high energy alongside micronutrients simultaneously, leading to calorie overload and undermining the beneficial calorie-to-nutrient trade-off,” noted psychologist Annika Flynn of the University of Bristol.
In contrast, wholefoods promote a healthy competition where consumers favor nutrient-dense options, like fruits and vegetables, over energy-rich items such as pasta or meats.
This research offers valuable insights into diet and healthy eating, indicating that overeating may not be the core issue. Instead, researchers point out that UPFs often “nudge” us towards calorie-dense foods.
The convenience and longevity of UPFs have raised concerns about their health risks, including links to obesity and early signs of certain diseases, like Parkinson’s.
More research will be necessary to determine the nature of this nutritional intelligence—whether it’s common, innate, or influenced by social factors. But this study underscores that weight loss isn’t solely about portion sizes and highlights the downsides of relying too heavily on UPFs.
Mark Schatzker, a food writer at McGill University, added, “If participants had only consumed calorie-dense foods, they would have likely missed out on essential vitamins and minerals, leading to deficiencies. Those gaps were filled by lower-calorie fruits and vegetables.”
The findings have been published in the American Journal of Clinical Nutrition.
