(OR24-06-23) Replacing Ultra-Processed Foods With Minimally Processed Foods Enhances 6-Month Weight Loss Among Participants in the POUNDS Lost Trial

Objectives: Population studies demonstrate an association between higher intake of ultra-processed foods (UPFs) and risk of obesity. To test whether intake of UPFs was associated with differential weight change within an energy-restricted dietary intervention, we examined whether replacing UPFs with minimally processed foods and culinary ingredients was associated with greater 6-month weight change in the Preventing Overweight Using Novel Dietary Strategies (POUNDS Lost) Trial, a randomized clinical trial that explored the effects of four energy- restricted diets of varying macronutrient distributions on weight loss.

Methods: We examined a subset of 356 participants with dietary data from the POUNDS Lost trial with BMI ≥ 25 kg/m². Percent energy intake (i.e., %kcal) from the 4 NOVA food processing groups was estimated from 24-hour recalls. Multivariable-adjusted substitution models examined whether replacing %kcal from UPFs with minimally processed foods and culinary ingredients (NOVA group 1+2), holding processed food (NOVA group 3) %kcal constant and adjusting for age, sex, race/ethnicity, diet arm, total kcal, prescribed energy deficit, and baseline body weight (kg), were associated with differences in weight loss, total percentage of body fat reduction, and waist circumference reduction at 6 months.

Results: Participants were on average 53.2 (± 8.8) years, 85% white, 55% female, 58.2% were non-smokers, 71% had college or higher degrees with an average BMI of 32.7 kg/m² at baseline. In multivariable analyses, replacing 10% of UPF kcal with NOVA group 1+2 kcal was associated with 0.51 kg greater 6-month weight loss (95%CI: -0.93, -0.09, p=0.02) and 0.26% greater 6-month percentage reduction in body fat (95%CI: -0.49, -0.30, p=0.03, n=309), but not significantly associated with 6-month changes in waist circumference (ß=-0.46, 95%CI: -0.96, 0.30, p=0.07).

Conclusions: Isocaloric substitution of UPFs with minimally processed foods and culinary ingredients (NOVA group 1+2) enhanced weight loss in the POUNDS Lost trial. Future research is needed to explore the mechanisms linking UPF with regulation of body weight and adiposity beyond energy intake. For people under energy restriction, substituting UPFs with minimally processed foods and culinary ingredients (NOVA group 1+2) may be a promising strategy to facilitate weight loss.

Funding Sources: N/A