Abstract P288: The Effect of a Time Restricted Eating Approach vs. Standard Heart Healthy Dietary Counseling on Cardiometabolic Health Measures in Adults With Abdominal Obesity: A Randomized Pilot Trial
Authors: Wong Theodora , Hirahatake Kristin , Nguyen Tiffany , Corral Carlos Athena , Odegaard Andrew O 
Published: March 2019

Introduction:
Basic and population level research suggest that meal timing and circadian rhythms are linked with cardiometabolic health. However, interventions that aim to optimally align meal timing with circadian rhythms have an unclear clinical impact on cardiometabolic risk; a critical gap since insight into the interplay between the noted factors may have important preventive and therapeutic implications. To begin addressing this gap, we carried out a randomized dietary intervention trial comparing a time restricted eating (TRE) intervention to standard dietary counseling (STD) for cardiometabolic health as recommended by the AHA and the Academy of Nutrition and Dietetics.

Hypothesis:
A STD dietary intervention will differentially improve measures of clinical cardiometabolic health compared to a TRE dietary intervention.

Methods:
Design:
Randomized parallel arm pilot trial with 1-week run in period and 8-week intervention period.
Participants
: 30 adults with abdominal obesity, free of major chronic disease, with interest in improving cardiometabolic health status via dietary counseling with a Registered Dietitian (RD).
Intervention
: All participants received 4 RD sessions, and were blinded to the nature of the other arm.
TRE
- RD counseling specifically on meal timing with no mention of content. Explicit directions for daily 12 hour TRE regimen representing the theoretical optimal conditions for cardiometabolic health to begin upon waking.
STD-
RD counseling specifically on content of dietary pattern with no mention of meal timing.
Measurements:
All clinical measures were collected by standardized protocol. Diet was assessed by random 24 hour recalls during the run-in (n=2), and intervention (n=3). Blinded continuous glucose monitors assessed adherence, and physical activity/sleep data were collected objectively by wearable device.
Analysis:
Standard intent-to-treat analyses utilizing ordinary least-squares linear regression models, adjusted for baseline measurements to compare participants across assignment groups.

Results:
30 participants (26 women) were randomized, mean (SD) age 42 (13) years and 28 completed. The STD intervention reduced the triglyceride (TG):HDL ratio (2.7 to 2.5), LDL (mg/dL) (118 to 107), blood pressure (BP) (118/74 to 114/72), and increased dietary quality (HEI-2015 score, 57 to 63). The TRE intervention also reduced the (TG):HDL ratio (2.8 to 2.6), LDL (109 to 108), BP (123/78 to 119/74), and increased dietary quality (HEI-2015 score, 50 to 54). P < 0.05 comparing STD to TRE for LDL.

Conclusions:
Both interventions improved cardiometabolic health and diet quality suggesting a TRE approach may be a useful counseling approach for clinical cardiometabolic health. The STD arm appeared to have stronger effects for LDL compared to TRE, but only a larger and longer trial will provide a definitive answer for any measure.