Association of Ultra-Processed Food Intake with Insulin Secretion and Sensitivity in Mexican American Children: Results from the SAFARI Study.

Background/Objectives: There is increasing interest in and evidence for the role of ultra-processed foods (UPFs) in cardiometabolic risk. We tested the hypothesis that UPF intake score derived from dietary history is associated with measures of insulin secretion and sensitivity in a family setting even when the process of type 2 diabetes is still to ensue. Methods: We used data from our well-characterized San Antonio Family Assessment of Metabolic Risk Indicators in Youth (SAFARI) study cohort of nondiabetic children (aged 6-17 years). Dietary history was assessed using the Block Food Frequency Questionnaire. Outcomes of interest were 19 clinically useful indexes of insulin secretion/sensitivity based on fasting and oral glucose tolerance test results. Since the SAFARI study employed a family study design, we used polygenic regression models that adjusted for complex interactions between age and sex and accounted for important comorbidities. Results: A total of 53.3% of daily energy intake was contributed by UPF. Of the 19 indexes tested for association with the UPF score, we found a statistically significant association with measures of insulin resistance and beta cell function and with three indexes based on the results of oral glucose tolerance test as follows: Matsuda index (β = -0.0962, p = 0.0262), insulinogenic index at 30 min (β = 0.1779, p = 0.0006) and disposition index at 30 min (β = 0.1538, p = 0.0061). Conclusions: Even in nondiabetic children there was a significant and independent association of UPF intake with insulin secretion and sensitivity. Future studies need to investigate this association in larger, longitudinal settings and in randomized trials controlling potential systematic errors.