Clinical Trials of Effects of Time Restricted Eating on Health Parameters in Adults

In a randomized controlled trial we will research the effect of calorie restriction with early and mid-day time-restricted eating (TRE) and daily calorie restriction on weight loss and human health parameters. Participants will be divided into three groups: early time-restriction group (8:00 AM to 4:00 PM), mid-day restriction group (1:00 PM to 9:00 PM) and daily calorie restriction group (8:00 AM to 9:00 PM). Participants will follow dietary strategy with three planned meals and calorie restriction. Anthropometrical and biochemical parameters will be measured at baseline, after one month, two months and at after three months of intervention. Resting metabolic rate, ultrasound scan of abdomen and ultrasound scan of carotid arteries will be measured at baseline and after three months of intervention. In addition, stool samples will be also taken at baseline and after three months of intervention.

Obesity has become one of the world's most common diseases and is a major global public health challenge. Obesity contributes to an increased risk of developing various chronic diseases, such as diabetes, metabolic syndrome, hypertension, cardiovascular and kidney diseases and many others. Reducing excess body weight and improving eating habits decreases risk of disease and mortality. A lot of dietary strategies for weight loss are known and most of them are based on daily calorie restriction. Recently, an increasingly popular dietary strategy has been "time restricted eating (TRE)". In this strategy, all calorie intake is restricted within a consistent interval of less than 12 hours (4 - 10 hours). Eating window is limited to early part of the day - early TRE or mid-day TRE. Research shows that TRE has a number of beneficial effect on individuals, including weight loss, improvement of insulin sensitivity, hypercholesterolaemia, circadian rhythm of hormone secretion and other. Which TRE (early or mid-day TRE) has better health effects is still being investigated. It is also not clear how the timing, number and composition of individual meals affect on the health indicators, mentioned previously.

Therefore, the aim of our study is to evaluate and compare the effects of calorie restriction with early and mid-day time-restricted eating (TRE) and daily calorie restriction on weight loss and human health parameters in adults with at least two components of metabolic syndrome and yet not receiving any medication. The components of metabolic syndrome (lipid profile, blood pressure, anthropometry, inflammation status, glucose levels), antioxidative status, hormones (leptin, ghrelin, cortisol, insulin, adiponectin, cholecystokinin, melatonin, BDNF, IGF-1) will be measured. In addition changes in gene expression of different proteins will be examined. Moreover, stool samples will be also taken at baseline and after three months of intervention.

Eligibility Criteria:
Inclusion Criteria:

* BMI 25-35 kg/m2

  + one of the following criteria:
* Increased waist circumference ≥ 94 cm in men and ≥ 80 cm in women
* Fasting plasma glucose \> 5,6 mmol/L
* Elevated fasting plasma triglycerides 1,7 mmol/l
* Reduced high-density lipoprotein (HDL)-cholesterol \< 1,0 mmol/l for men, \< 1,3 mmol/l for women
* Elevated blood pressure, systolic blood pressure \> 130 mm Hg and diastolic blood pressure \> 85 mm Hg
* Without medicals for hypertension and hypercholesterolemia
* Morning or afternoon working time

Exclusion Criteria:

* Pregnant or plan to be become pregnant
* Lactating women
* Active smoking
* Diagnosis of diabetes
* Eating disorders
* Currently enrolled in a weight-management program
* Uncontrolled medical condition due to gastrointestinal, psychiatric, rheumatologic, oncologic, hematologic or endocrine diseases
* History of tumor
* History of serious cardiovascular or cerebrovascular diseases
* Taking medicines that may affect weight and appetite