Benefits of Time Restricted Eating in Patients with Metabolic Syndrome

Dr. Gerald M. Reaven was one of the first clinicians to put forth the concept that the syndrome of insulin resistance, commonly associated with type 2 diabetes, was the root cause of glucose intolerance, elevated serum levels of low-density lipoprotein (LDL: the so-called "bad cholesterol") along with reduced serum levels of high-density lipoprotein (HDL: the so-called "good cholesterol"), and hypertension. This early clinical concept has evolved into what is now referred to as the metabolic syndrome. The metabolic syndrome, MetS (also once referred to as Syndrome X), is a disorder that defines a combination of metabolic and cardiovascular risk determinants. These risk factors include insulin resistance, hyperinsulinemia, central adiposity (obesity associated with excess fat deposits around the waist), dyslipidemia, glucose intolerance, hypertension, pro-inflammatory status, and microalbuminemia.

The hallmark feature of MetS is indeed insulin resistance. Several other clinical abnormalities are also associated with MetS including non-alcoholic fatty liver disease (NAFLD), atherosclerosis, oxidative stress, and polycystic ovary syndrome (PCOS).

Although obesity, ectopic fat accumulation, and an intravascular pro-inflammatory status are central to the pathology of MetS, not all obese individuals develop MetS and not all individuals with MetS are obese. These observations indicate that MetS has a multifactorial etiology that involves a series of complex interactions between a particular individuals dietary habits, hormonal status, and genetic background.

A recent report in the prestigious journal, Cell Metabolism, has shown that a diet structured around time restricted eating can have positive benefits in patients with MetS. This type of diet stimulates weight loss, and reductions in blood pressure and serum lipid profiles all of which a critical to reducing the dyslipidemia, glucose intolerance, hypertension, pro-inflammatory status typified in MetS patients:

Ten-Hour Time-Restricted Eating Reduces Weight, Blood Pressure, and Atherogenic Lipids in Patients with Metabolic Syndrome

The premise of time restricted feeding, and indeed results from several studies have shown,  is that this type of diet supports circadian regulation of the endocrine system, autonomic nervous system, and nutrient metabolism which in turn contributes to metabolic and physiological homeostasis.

Participants in this study were diagnosed with MetS, many of whom were also on medications for hypertension and hypercholesterolemia. Prior to the onset of the study, the participants had a baseline mean daily eating window of more than 14 hours. The participants were placed on a time restricted diet such that all dietary intake occurred within a consistent self-selected

10 hour window. The participants continued this time restricted dieting for a period of 12 weeks.

The overall outcomes found in this study were that this particular time restricted eating regimen resulted in significant improvement in cardiometabolic health

for patients with MetS.

At the end of the 12 weeks of participation observations showed significant reductions in

body weight, waist circumference, body mass index (BMI), percent body fat, visceral fat rating, systolic and diastolic blood pressure, total cholesterol, LDL cholesterol, and non-HDL cholesterol. 

Parameters of health that were not statistically improved were average plasma glucose, fasting insulin, serum triglycerides, and the pro-inflammatory marker, C-reactive protein (CRP). However, these parameters did demonstrate a positive trend in the desirable direction. Participants who began the study with elevated fasting plasma glucose (>100 mg/dL) and/or HbA1c (>5.7%) showed a significant reduction in HbA1c at the conclusion of the study.

Another positive finding from this study was that the participants had better quality and longer periods of sleep, as measured both by self-assessment and the wearing of sleep monitoring devices. The participants also reported being more active.

TAKE HOME: As I have written in several posts, what we eat, and when we eat, and how often we eat can have significant benefits in all measures of health. This study demonstrates yet again that time restricted eating, which includes diets such as alternate day fasting and modifications thereof, are safe and of profound benefits, especially in individuals with pre-existing health issues.