What is time-restricted eating?
Time-restricted eating (TRE) is a dietary pattern that limits daily caloric intake to a defined window. This page summarizes registered trials and a randomized feeding study, with no dosing or medical guidance.
What is time-restricted eating?
Time-restricted eating (TRE) is a dietary pattern in which all daily caloric intake is confined to a defined window, typically 10 hours or less, with the remaining hours constituting a fasting period. Synonyms include time-restricted feeding (TRF) and, in some protocols, chrono-nutrition or ChronoFeeding (CF). TRE is a class of intermittent fasting; it does not specify macronutrient composition or total energy intake, and in controlled feeding studies it is often applied isocalorically and eucalorically relative to a comparator pattern. The evidence block does not provide a sequence, formula, or molecular weight for TRE, as it is a behavioral schedule rather than a molecular entity.
The work summarized here centers on metabolic and circadian pathways, including insulin signaling and glycemic control, appetite-regulating hormones such as leptin and adiponectin, inflammatory markers such as C-reactive protein (CRP) and soluble receptor for advanced glycation end-products (sRAGE), and, in one protocol, the glucagon-like peptide-1 (GLP-1) receptor family as a pharmacological comparator.
Research Studies
TRE and appetite, eating behavior, and inflammatory markers in adults with obesity and prediabetes
The Time-Restricted Intake of Meals (TRIM) study was a 12-week randomized isocaloric and eucaloric feeding trial comparing 10-hour TRE to a 16-hour usual eating pattern (UEP) in adults with obesity and either prediabetes or diet-controlled type 2 diabetes. A post hoc analysis investigated TRE's effects on eating behavior, appetite hormones, and inflammatory markers. Participants completed the Three-Factor Eating Questionnaire (Restraint, Disinhibition, Hunger) and provided fasting blood samples for leptin, adiponectin, CRP, cortisol, and sRAGE at pre- and post-intervention timepoints [1].
TRE and weight-loss maintenance in adults with overweight or obesity
A multi-center, 2-arm randomized controlled trial across six regions in China is targeting overweight or obese adults who have recently achieved a short-term weight reduction of at least 5% of body weight. The trial will evaluate whether a 10-hour daily TRE regimen can more effectively prevent weight regain compared to standard weight maintenance counseling alone. Both the intervention and control groups receive the same frequency and intensity of nutritional counseling for weight maintenance; the only difference is the TRE schedule [2].
TRE, GLP-1 receptor agonists, and a heart-healthy diet in prostate cancer patients on androgen deprivation therapy
The phase II IMPACT-ADT trial compares time-restricted eating, GLP-1 receptor agonists (semaglutide and tirzepatide), and an American Heart Association (AHA) heart-healthy diet (HHD) intervention on cardiovascular and metabolic outcomes in prostate cancer patients undergoing androgen deprivation therapy (ADT). Prostate cancer patients receiving ADT are at increased risk of cardiovascular disease, thought to be due to treatment-related metabolic changes that may result in increased weight, body fat, insulin resistance, and increased risk [3].
Urolithin A with restricted eating in adults with BMI above 30
A study will test whether daily Urolithin A (500 mg) for 6 months helps adults with obesity lose weight while preserving functional muscle mass and improving markers of mitochondrial health, inflammation, and metabolism. All participants receive the same structured lifestyle program (nutrition and sleep guidance); half receive Urolithin A and half a matching placebo. Weight loss can improve health but may also reduce skeletal muscle, especially in people with obesity. Aging and obesity are both linked to mitochondrial dysfunction, impaired autophagy/mitophagy, oxidative stress, and low-grade inflammation. Urolithin A is described as a gut-derived, diet-related compound [4].
TRE with motivational sessions in adult survivors of childhood cancer
A study will look at whether motivational sessions, including regular calls with a trained health coach, in combination with time-restricted eating, is an effective way to achieve weight loss and lower cardiometabolic risk in adult survivors of childhood cancer. The researchers will compare this intervention to the usual approach, which is to review educational materials and measure weight once a month. This study will not provide treatment for any disease or cancer [5].
TRE and glycemic control in type 2 diabetes
A 1-year study aims to investigate the effectiveness of implementing a time-restricted eating-based intervention on glycaemic control, body weight and composition, cardiometabolic risk factors, and behaviour in individuals with overweight/obesity and type 2 diabetes (T2D) [6].
Chrono-nutrition, microbiome, and ADHD
A randomized controlled pilot study will be conducted with 60 adults diagnosed with ADHD, aged 18 to 65, who have extended eating habits (more than 14 hours a day) and sleep problems. The project seeks to understand how an intervention based on time-restricted eating (ChronoFeeding or CF) can improve quality of life, behavior, sleep, and gut health in adults with ADHD who have alterations in their circadian rhythms. It will also study how this intervention affects biological markers, such as microbiota (gut and saliva bacteria), inflammation, and oxidative stress, in both humans and animal models [7].
TRE and metabolic abnormalities in polycystic ovarian syndrome
Polycystic ovarian syndrome (PCOS) is associated with metabolic symptoms such as hyperinsulinemia. Time-restricted eating may reduce serum insulin and improve insulin resistance in patients with PCOS. Currently, there are few studies investigating time-restricted eating in patients with PCOS. Investigators plan to test the feasibility of time-restricted eating in the management of PCOS by means of a real-world clinical intervention, determining if an 18:6 eating protocol reduces insulin levels by means of a randomised controlled crossover trial [8].
Comparison of TRE protocols across registered studies
| Study | Population | TRE protocol | Comparator | Primary focus |
|---|---|---|---|---|
| TRIM post hoc [1] | Adults with obesity and prediabetes or diet-controlled T2D | 10-hour TRE | 16-hour usual eating pattern | Appetite, eating behavior, inflammatory markers |
| NCT07163455 [2] | Overweight or obese adults after ≥5% weight loss | 10-hour TRE | Standard weight maintenance counseling | Weight regain prevention |
| IMPACT-ADT [3] | Prostate cancer patients on ADT | TRE | GLP-1 RA (semaglutide, tirzepatide); AHA heart-healthy diet | Cardiovascular and metabolic outcomes |
| NCT07377136 [4] | Adults with BMI >30 | Restricted eating plus Urolithin A 500 mg daily | Placebo plus same lifestyle program | Weight loss, muscle mass, mitochondrial and inflammatory markers |
| NCT07009288 [5] | Adult survivors of childhood cancer | TRE plus motivational sessions | Usual approach (educational materials, monthly weight) | Weight loss, cardiometabolic risk |
| NCT06152588 [6] | Overweight/obesity and T2D | TRE-based intervention | Not specified in evidence block | Glycaemic control, body weight and composition, cardiometabolic risk, behaviour |
| NCT07821060 [7] | Adults with ADHD and circadian alterations | ChronoFeeding (TRE) | Not specified in evidence block | Quality of life, behavior, sleep, gut health, microbiota, inflammation, oxidative stress |
| NCT05126199 [8] | PCOS | 18:6 eating protocol | Randomised controlled crossover | Serum insulin, insulin resistance, feasibility |
If you are reading this for personal health reasons
The materials and interventions described here are presented for laboratory research and clinical study purposes only; we do not sell them for personal use and we do not provide dosing or medical guidance. Anyone considering a compound or a dietary schedule for themselves should speak to a licensed clinician. This page is not medical advice.
Sources
- [1] Time-Restricted Eating on Appetite and Inflammation in Adults With Obesity and Prediabetes: A Randomized Feeding Study. https://pubmed.ncbi.nlm.nih.gov/42508996/
- [2] Time-Restricted Eating for Weight-Loss Maintenance. https://clinicaltrials.gov/study/NCT07163455
- [3] Metabolic Interventions (Time-Restricted Eating, GLP1 Receptor Agonist, and Heart Healthy Diet) to Improve Cardiometabolic Health in Prostate Cancer Patients During Androgen Deprivation Therapy, IMPACT-ADT Trial. https://clinicaltrials.gov/study/NCT07202247
- [4] Influence of the Urolithin A on the Population With BMI Higher Than 30 During Restricted Eating. https://clinicaltrials.gov/study/NCT07377136
- [5] A Study of Time-Restricted Eating in Childhood Cancer Survivors. https://clinicaltrials.gov/study/NCT07009288
- [6] Restricted Eating Time in the Treatment of Type 2 Diabetes. https://clinicaltrials.gov/study/NCT06152588
- [7] Developing Microbiome and Dietary Strategies Based on Chrono-nutrition for Targeting ADHD. https://clinicaltrials.gov/study/NCT07821060
- [8] Time-restricted Eating to Improve Metabolic Abnormalities in Polycystic Ovarian Syndrome. https://clinicaltrials.gov/study/NCT05126199