1714-P: Higher Initial Diet Quality Predicts Shorter Weight Loss Period prior to an Involuntary Weight Loss Plateau

It is currently unknown what factor(s) may promote entry into a weight loss plateau. Given intensive lifestyle interventions (ILI) for weight loss include changes in diet, we evaluated how diet quality impacts characteristics of a weight loss plateau. Daily weights were obtained remotely via electronic scale from 62 adults with obesity (73% female, mean age 42±11 y and BMI 37±5 kg/m2) undergoing a 24-week ILI. Periods (≥14 d) of active weight loss or plateau were identified by threshold regression modeling. Active weight loss was defined as a per day % weight change from baseline equivalent to ≥0.5 lb loss/wk and a weight loss plateau as ±0.25lbs/wk after a period of active weight loss (in which ≥3.5% weight loss was achieved). Three unannounced self-reported ASA24 dietary recalls were obtained at baseline and 3 mo. Diet quality was assessed by the healthy eating index (HEI)-2015. 53% reached a plateau after active weight loss (27% did not achieve >3.5% weight loss, 19% re-gained directly after loss). Weight loss (i.e., plateau depth) was associated with longer time to plateau (β=–10d, P