Intermittent fasting and changes in Galectin-3: A secondary analysis of a randomized controlled trial of disease-free subjects

Intermittent fasting reduces risk of interrelated cardiometabolic diseases, including type 2 diabetes and heart failure (HF). Previously, we reported that intermittent fasting reduced homeostasis model assessment of insulin resistance (HOMA-IR) and Metabolic Syndrome Score (MSS) in the WONDERFUL Trial. Galectin-3 may act to reduce insulin resistance. This post hoc evaluation assessed whether intermittent fasting increased galectin-3.The WONDERFUL Trial enrolled adults ages 21-70 years with ≥1 metabolic syndrome features or type 2 diabetes who were not taking anti-diabetic medication, were free of statins, and had elevated LDL-C. Subjects were randomized to water-only 24-h intermittent fasting conducted twice-per-week for 4 weeks and once-per-week for 22 weeks or to a parallel control arm with ad libitum energy intake. The study evaluated 26-week change scores of galectin-3 and other biomarkers. Overall, n = 67 subjects (intermittent fasting: n = 36; control: n = 31) completed the trial and had galectin-3 results. At 26-weeks, the galectin-3 change score was increased by intermittent fasting (median: 0.793 ng/mL, IQR: -0.538, 2.245) versus control (median: -0.332 ng/mL, IQR: -0.992, 0.776; p = 0.021). Galectin-3 changes correlated inversely with 26-week change scores of HOMA-IR (r = -0.288, p = 0.018) and MSS (r = -0.238, p = 0.052). Other HF biomarkers were unchanged by fasting.A 24-h water-only intermittent fasting regimen increased galectin-3. The fasting-triggered galectin-3 elevation was inversely correlated with declines in HOMA-IR and MSS. This may be an evolutionary adaptive survival response that protects human health by modifying disease risks, including by reducing inflammation and insulin resistance.Clinicaltrials.gov, NCT02770313 (registered on May 12, 2016; first subject enrolled: November 30, 2016; final subject's 26-week study visit: February 19, 2020).