Influence of autonomic function on the thermic effect of food and postprandial insulin sensitivity in individuals with obesity,submitted to a test meal with or without ultra-processed foods: Secondary analysis of a randomized trial

Abstract

Background

The role of the autonomic nervous system in postprandial metabolic responses to ultra-processed foods (UPFs) in individuals with obesity remains uncertain.

Objective

To investigate how fasting autonomic function, assessed by heart rate variability (HRV), affects the thermogenic response and insulin sensitivity after meals with or without UPF in individuals with obesity.

Methods

Participants consumed one of two matched test meals differing only in UPF content. Fasting HRV was assessed, and associations with postprandial glucose, insulin, homeostatic model assessment of insulin resistance (HOMA-IR), and the thermic effect of food (TEF) were analyzed using mixed-ANCOVA and linear regression models, adjusted for age, sex, and group.

Results

40 individuals were analyzed. Considering the two groups together, there was a negative relationship between RMSSD and blood glucose variation (β = −7.95, CI95%: −13.05; −2.84) and a positive relationship between LF/HF and blood glucose variation (β = 12.05, CI95%: 2.35; 21.76), insulin (β = 16.90, CI95%: 1.90; 31.90) and HOMA-IR (β = 1.79, CI95%: 0.27; 3.23). When considering interaction with groups, RMSSD showed a positive relationship with TEF in the control meal and a negative relationship in the UPF meal (P-interaction = 0.04).

Conclusion

Fasting autonomic function influences postprandial insulin sensitivity in individuals with obesity, regardless of the UPF content of the meal. The influence on TEF appears to depend on the meal's UPF content.

Clinical trial registry (ReBEC)

RBR-56nsh92: https://ensaiosclinicos.gov.br/rg/RBR-56nsh92