(P13-018-25) Metabolic and Body Composition Outcomes of Low Ultra-Processed Feeding in a Free-living Environment

Objectives: The increase of ultra-processed foods (UPF) in the American diet may increase risk of chronic metabolic conditions/diseases. The study objective is to determine the prospective metabolic and body composition outcomes after striving to consume a low-UPF diet in free-living settings.

Methods: For this ongoing clinical trial, 53 participants were randomized to either consume their normal diet (ND; n=27) or to consume a diet that is primarily composed of unprocessed or minimally processed foods (MPF; n=26) for 6 months. Outcomes were measured at baseline and 6 months after enrollment. Participant BMI, relative fat mass, and relative lean mass were measured using dual-energy X-ray absorptiometry (DXA), with waist circumference measured prior to the scan. Fasting cholesterol, triglycerides, HDL, LDL, and glucose were measured using point-of-care reagent discs.

Results: The ND group exhibited a significant increase in BMI from baseline (31.32 ± 9.36 kg/m²) to 6 months (31.85 ± 9.97 kg/m²; p = 0.017). There were no significant differences in BMI between groups at either time point, nor was there a difference in the MPF group over time (baseline: 30.84 ± 7.50 kg/m²; 6 months: 30.63 ± 7.47 kg/m²; p = 0.34). The ND group also had a significant increase in waist circumference from baseline (39.16 ± 8.34 in) to 6 months (40.05 ± 8.37 in; p = 0.011), and there was a significant increase in relative body fat from baseline (34.48 ± 9.65%) to 6 months (35.91 ± 9.60%; p = 0.0005). There were no significant differences between groups or within the MPF group over time for waist circumference and relative body fat. The ND group exhibited a significant decrease in relative lean mass between baseline (62.61 ± 9.04%) and 6 months (61.23 ± 9.06%; p = 0.0006), and this was not seen between groups or within the MPF group. There were no significant differences observed for measured metabolic markers. There was an increase in fasting glucose within the ND group from baseline (105.2 ± 25.0 mg/dL) to 6 months (112.0 ± 47.6 mg/dL) that was marginally different (p = 0.0502).

Conclusions: Although people assigned to eat a MPF diet did not exhibit improvements in body composition, they did avoid increases in BMI, waist circumference, and relative body fat, and a decrease in relative muscle mass, that were observed in the ND group.

Funding Sources: USDA NIFA AFRI Seed Grant (2023-69015-39600)