Physical Activity Level Impacts Food Choice Following Exposure To A Diet High In Ultra-processed Foods

Ultra-processed foods (UPF) comprise ~68% and 59% of total energy intake in US adolescents and young adults, respectively. The greatest age-related weight gain occurs in the early to mid-20’s. Strategies to improve food choices and diet quality in this population are needed. Physical activity (PA) is important to avoid weight gain but its impact on food choice, particularly UPF, is uncertain. PURPOSE: To determine if higher vs lower levels of aerobic PA impact the consumption of UPF and non-UPF following exposure to diets high in UPF (81% energy, ‘UPF’) and free of UPF (0% energy, ‘non-UPF’). METHODS: Thirteen individuals (54% female) aged 18-25 years were provided with eucaloric UPF and non-UPF diets for 2 weeks each[MOU1] . During each diet period, PA was assessed with an accelerometer for 4 days. Participants were classified as active (>150 min) vs less active (<150 min) at each diet period. An ad libitum buffet meal containing similar UPF and non-UPF food items (e.g., UPF & non-UPF cereals) followed each diet period. Wilcoxon signed-rank tests were used to determine if PA level impacted energy (kcal) intake and the consumption of UPF and non-UPF energy at the buffet meal. RESULTS: PA subgroups did not differ based on sex, BMI, and body weight pre/post-diet. At the buffet meal following the UPF diet, active participants (n = 7) consumed more non-UPF kcal than less active participants (n = 6) (mean difference = 192 kcal; p = 0.02), with a trend toward increased total kcal (mean difference = 268 kcal; p = 0.07, d = 0.68). Groups did not differ in UPF kcal intake (p = 0.70). Within the active group post-UPF diet, there was a large effect size between UPF and non-UPF kcal intake (307 ± 215 UPF kcal [39% energy] vs 477 ± 123 non-UPF kcal [61% energy], d = 0.97), although not significantly different (p = 0.20). Within the less active group, there were no differences in UPF and non-UPF consumption, with a medium effect size (230 ± 142 UPF kcal [45% energy] vs 286 ± 143 non-UPF kcal [55% energy], p = 0.6, d = 0.39). Following the non-UPF diet, kcal intake at the buffet meal did not differ between PA groups (8 active, 5 less active). CONCLUSIONS: Given the prevalent UPF consumption among US youth, these results suggest that being physically active could be protective against UPF exposure and improve dietary choices. Larger studies are needed to confirm these findings. NIH R21HD109722