New Study Suggests Minimally Processed Foods Aid Weight Loss

If you needed another reason to cut back on ultra-processed foods, a recent study shows that people tend to lose more weight when they switch to minimally processed diets compared to their ultra-processed counterparts. This study, conducted by researchers at University College London, involved participants following two different diets over a span of six months. They would follow one diet for eight weeks, then take a break for four weeks, and finally switch to the other diet for another eight weeks.

Results indicated participants lost more weight and unhealthy fat while on the minimally processed diet. Published in Nature Medicine, the researchers noted that ultra-processed diets might be particularly good at triggering food cravings, which complicates weight management.

Now, defining ultra-processed foods can be a bit tricky. Generally, these are foods that have undergone extensive industrial processing—think breakfast sausages, candy, or soda. A growing body of evidence suggests that diets high in ultra-processed foods tend to be less healthy, possibly increasing the risk for certain diseases. However, much of this research points to correlations rather than direct cause-and-effect relationships. Conducting clinical trials in nutrition science is often challenging, especially when it comes to securing funding, as highlighted by the researchers.

One of the study’s authors, Sam Dicken, pointed out that while clinical trials are costly, they were fortunate to receive joint funding from a medical charity and a UK NGO.

The study included 55 adult volunteers who were assigned either a minimally processed or an ultra-processed diet, based on prepackaged meals. Each diet was designed to align with UK dietary recommendations, ensuring they were roughly equal in nutritional quality. For instance, breakfast cereal was a part of the ultra-processed diet, while the minimally processed equivalent was overnight oats.

Both diets led to weight loss, but the difference was notable. Participants on the minimally processed diet lost about 2% of their baseline weight, whereas those on the ultra-processed plan lost just 1% and tended to consume slightly more calories. Furthermore, those who lost weight on the minimally processed diet saw a more considerable reduction in fat mass and visceral fat, which is more closely linked to health issues.

Dicken emphasized the value of adhering to government dietary guidelines. This study indicates that sticking to minimally processed foods may be more beneficial for weight loss. As for why ultra-processed foods seem to hinder dieting, the researchers have some educated conjectures.

Ultra-processed foods often have more enticing textures and artificially enhanced flavors, making them easier and tastier to eat. Interestingly, while participants reported similar satisfaction levels from both diets, they felt they had better control over cravings when consuming minimally processed foods. However, Dicken noted that these potential explanations need further investigation.

The research team has already kicked off another study that aims to develop a behavioral support program focused on reducing the intake of ultra-processed foods. Dicken warns, though, that merely focusing on individual habits won’t be enough; wider societal changes are essential to make healthier diets accessible and affordable for everyone.