Time Restricted Eating in Childhood Obesity (TRECO)

The goal of this clinical trial is to learn if time-restricted eating (TRE), an alternative method of reducing energy intake which has gained popularity in recent years, works to treat obesity in children. It will also learn about the safety and long-term adherence of 12-hour TRE, in comparison to calory restricted diet (CRD) . The main questions it aims to answer are:

1. Is the weight-losing effect of 12-hour TRE better than CRD?
2. Is 12-hour TRE easier to adhere to than CRD?

Researchers will compare 12-hour TRE to CRD (the primary treatment for obesity) to see if 12-hour TRE works to treat childhood obesity.

Participants will:

1. Follow the 12-hour TRE or CRD diet every day for 48 weeks;
2. Visit the clinic once every 4 weeks before 12 weeks and thereafter every 12 weeks for checkups and tests;
3. Keep a diary of their diet, physical activity, and symptoms

Childhood obesity is a major metabolic disorder affecting approximately 20% of children and adolescents. Calory-restricted diet (CRD) is the primary treatment for obesity, but adherence to CRD typically declines over time and many individuals who lose weight with this strategy regain it. Accumulating evidence suggests that time-restricted eating (TRE), an alternative method of reducing energy intake that has gained popularity in recent years, has a significant weight-losing effect on adult obesity. However, its weight-losing effect on childhood obesity is still lacking trial evidence.

The overall objective of this study is to test the effectiveness of 12-hour TRE on weight loss for childhood obesity in comparison with CRD. The secondary objective is to compare the long-term adherence and weight-losing effect between the two dietary interventions.

The TRECO study is an open-label, blinded endpoint, parallel design, randomized controlled trial planned to enroll 128 patients with childhood obesity (8-17 years old, BMI-Z value \&gt;2), randomized by sex and age (12 years old) into zonal groups, and on the basis of the conventional non-pharmacological interventions, TRE was given to the intervention group, and CRD was given to the control group, and the short-term effect of TRE was observed after 12 weeks of intervention The short-term effect of TRE was observed after 12 weeks of intervention, i.e., to compare the difference in the magnitude of BMI-Z reduction between the two groups. The intervention was extended to 48 weeks to observe the long-term effect of TRE by comparing the difference in the reduction of BMI-Z between the two groups.

Eligibility Criteria:
Inclusion Criteria:

* Age: 8-17 years.
* Childhood obesity: BMI-z score \&gt; 2.
* Agree to participate in this study and signed an informed consent form.

Exclusion Criteria:

* Individuals who have been actively fasting for more than 12 hours/day.
* Diabetic patients on hypoglycemic medications.
* Individuals undergoing weight loss interventions or previous bariatric surgery.
* Individuals with psychiatric, intellectual developmental disorders, or aphasia.
* Individuals on appetite or weight-suppressing medications within the last three months (e.g., antipsychotics, hypnotics, weight-loss drugs, insulin).