Time-Restricted Eating for Obesity

Overseen By Nadeeja N Wijayatunga, MBBS, MPhil, PhD, RDN

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Mississippi, Oxford

Must not be taking: Appetite suppressants, Anabolic steroids

Disqualifiers: Diabetes, Heart disease, Hypertension, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 3

46 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests whether time-restricted eating (TRE) helps individuals with obesity adhere to a specific eating schedule and improve their health. Participants will either consume all meals within an 8-hour window each day or maintain their usual eating patterns over 12 hours or more. The trial will monitor adherence to the schedule, calorie intake, and other health factors such as body fat and sleep quality. It is suitable for individuals aged 19 to 65 who have obesity, lead a mostly inactive lifestyle, and typically eat over a 12-hour period daily. As an unphased trial, this study provides a unique opportunity to explore lifestyle changes that could significantly enhance health.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but you cannot participate if you are taking medications that affect appetite.

What prior data suggests that time-restricted eating is safe for adults with obesity?

Research has shown that time-restricted eating (TRE) is generally safe for people with obesity. In studies, participants who ate only during an 8-hour window lost 3% to 5% of their weight over several months, with no reports of serious side effects. Early studies also suggest that TRE might reduce the risk of developing diabetes and heart disease, indicating it is safe and well-tolerated. Additionally, TRE has demonstrated effectiveness in aiding fat loss, with moderate to strong evidence supporting this benefit. Overall, current research does not reveal any major safety concerns, making TRE a potentially safe option for managing obesity. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about time-restricted eating (TRE) for obesity because it offers a unique approach to weight management without the need for calorie counting or special diets. Unlike traditional methods that often focus on reducing calorie intake through portion control or dietary restrictions, TRE simply limits eating to an 8-hour window each day. This method leverages the body's natural circadian rhythms, potentially improving metabolism and weight loss. Additionally, TRE is simple to implement and could lead to better adherence and long-term lifestyle changes compared to more complex dietary regimens.

What evidence suggests that time-restricted eating is effective for obesity?

This trial will compare Time-Restricted Eating (TRE) with a control group following their usual eating patterns. Studies have shown that TRE can aid in weight loss and improve health. Adults following TRE commonly lose 1% to 4% of their weight, and their waist size often decreases. TRE may also help reduce body fat, especially when calorie intake is reduced. Some research suggests that TRE can lower the risk of obesity-related issues like diabetes and heart disease. However, fasting blood sugar levels might not change significantly, even with weight loss. Overall, TRE is a promising method for managing weight and improving health. ^{3 5 6 7 8}

Are You a Good Fit for This Trial?

This trial is for healthy, sedentary adults aged 19-65 with obesity who are free-living. Participants should be willing to follow a time-restricted eating plan (16:8) for 8 weeks. The study excludes specific details on eligibility criteria provided.

Inclusion Criteria

Sedentary lifestyle (less than 150 minutes of self-reported moderate to vigorous activity per week)

Owns a smartphone

Apparently healthy

Exclusion Criteria

Works night shifts

Currently following any of the following restrictive diets - Keto/low carbohydrate/Vegan/Vegetarian/Intermittent fasting/Paleo/Calorie restriction/Any other restrictive diet

Participation in an exercise/nutrition/weight-loss program within the last 6 months

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1 week

1 visit (in-person)

Baseline

Baseline measurements and assessments are conducted

1 week

1 visit (in-person)

Intervention

Participants follow the 16:8 time-restricted eating (TRE) regimen or continue their usual eating patterns

8 weeks

Weekly virtual check-ins

Follow-up

Participants are monitored for safety and effectiveness after the intervention

4 weeks

1 visit (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• Time Restricted Eating

Trial Overview The study tests the adherence and safety of an 8-hour time-restricted eating pattern over an 8-week period compared to a non-fasting control group in obese individuals. It measures outcomes like calorie intake, body composition, diet quality, and quality of life.

How Is the Trial Designed?

Group I: Time Restricted Eating Group Experimental Treatment 1 Intervention

The TRE group will consume calorie-containing food and drinks only over an 8-hour window between 6 a.m. to 8 p.m. for 8 weeks. During the fasting period, they can take only calorie-free fluids.

Group II: Control Active Control 1 Intervention

They will follow their usual eating patterns and consume food over a period of 12 hours or more.

Who Is Running the Clinical Trial?

University of Mississippi, Oxford

Lead Sponsor

Trials

13

Recruited

840+

Published Research Related to This Trial

In a study involving 15 men over 8 weeks, time-restricted eating (TRE) significantly altered 24-hour profiles of key metabolic markers, including insulin and triglycerides, suggesting potential benefits for metabolic health.

TRE also influenced the expression of genes related to circadian rhythms and transcriptional regulation in subcutaneous adipose tissue, indicating a mechanism by which TRE may improve metabolic function.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Time-restricted eating alters the 24-hour profile of adipose tissue transcriptome in men with obesity. Zhao, L., Hutchison, AT., Liu, B., et al.[2023]

Time-restricted eating (TRE) has shown promising therapeutic effects in rodent studies, particularly in relation to body weight and metabolic health, but results in humans are inconsistent due to varying study designs and populations.

This review highlights the need for more standardized research on TRE in humans to better understand its effects and interactions with circadian biology, as well as to identify gaps in current knowledge for future studies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Complex physiology and clinical implications of time-restricted eating. Petersen, MC., Gallop, MR., Flores Ramos, S., et al.[2023]

Time-restricted eating (TRE) is emerging as a promising strategy for treating obesity and related health issues, addressing the challenges of long-term adherence to traditional hypocaloric diets.

While TRE may help with weight loss and metabolic health through mechanisms like reduced caloric intake and improved eating behaviors, there are significant limitations in current research, including inconsistencies in clinical trials and a lack of long-term safety data.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Time-restricted eating as a novel strategy for treatment of obesity and it's comorbid conditions]. Berkovskaya, MA., Gurova, OY., Khaykina, IA., et al.[2023]

Time-restricted eating (TRE) is a promising dietary strategy that can help improve metabolic health and restore circadian rhythms, potentially aiding in the prevention and treatment of obesity and its complications.

Current evidence from previous TRE trials suggests a need for more extensive clinical research, including large-scale controlled trials, to fully understand the efficacy and mechanisms of TRE in humans.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Research progress on the application of time-restricted eating in adult obesity and related metabolic diseases]. He, JH., Sun, CY., Liang, C.[2022]

In an 8-week pilot study involving 78 participants with obesity, those following a 14-hour time-restricted eating (TRE) schedule lost an average of 8.5% of their body weight, which was statistically significant compared to a 12-hour TRE group that lost 7.1%.

The 14:10 TRE group also experienced a significant reduction in fasting blood glucose levels by 7.6 mg/dl, indicating potential metabolic benefits, especially for those with elevated blood glucose at baseline.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of time restricted eating on body weight and fasting glucose in participants with obesity: results of a randomized, controlled, virtual clinical trial. Peeke, PM., Greenway, FL., Billes, SK., et al.[2021]

In a study involving adults with obesity, both 4-hour and 6-hour time-restricted feeding (TRF) regimens led to comparable weight loss of about 3% over 8 weeks, along with improvements in insulin resistance and oxidative stress.

Participants in the TRF groups reduced their daily energy intake by approximately 550 kcal without needing to count calories, suggesting that TRF can be an effective and manageable approach for weight loss and improving cardiometabolic health.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of 4- and 6-h Time-Restricted Feeding on Weight and Cardiometabolic Health: A Randomized Controlled Trial in Adults with Obesity. Cienfuegos, S., Gabel, K., Kalam, F., et al.[2022]

In a 12-week study involving 14 adults with obesity, time-restricted feeding (8-hour eating window) led to a significant weight loss of about 2 kg, indicating potential efficacy for weight management.

Despite the weight loss, the study found no significant changes in the diversity or composition of the gut microbiome, suggesting that time-restricted feeding may not impact gut health in terms of microbial diversity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of time restricted feeding on the gut microbiome in adults with obesity: A pilot study. Gabel, K., Marcell, J., Cares, K., et al.[2022]

In a 12-week study involving 23 obese adults, time-restricted feeding (TRF) with an 8-hour eating window was found to be safe, as there were no significant changes in self-reported adverse events or disordered eating patterns.

The study suggests that TRF can effectively support weight loss in obese individuals without negatively impacting their health or body image perception.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety of 8-h time restricted feeding in adults with obesity. Gabel, K., Hoddy, KK., Varady, KA.[2019]

Time-restricted eating (TRE) significantly reduces body weight and fat mass while preserving fat-free mass, based on a meta-analysis of 19 clinical trials.

TRE also improves important metabolic parameters, including lower blood pressure, reduced fasting glucose levels, and better cholesterol profiles, suggesting it could be an effective strategy for managing obesity and metabolic dysfunction.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Beneficial Effects of Time-Restricted Eating on Metabolic Diseases: A Systemic Review and Meta-Analysis. Moon, S., Kang, J., Kim, SH., et al.[2021]

In a study involving 99 participants over three months, time-restricted eating (TRE) did not show significant differences in obesity-related outcomes based on the timing of food intake, whether early, medium, or late.

Participants who started eating earlier had a longer eating duration but the late eaters had a longer fasting period, suggesting that the timing of food intake may not be as crucial as previously thought, and further research is needed to clarify these findings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Early or Delayed Onset of Food Intake in Time-Restricted Eating: Associations with Markers of Obesity in a Secondary Analysis of Two Pilot Studies. Kesztyüs, D., Cermak, P., Kesztyüs, T., et al.[2023]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC11221496/

Time-restricted eating: Watching the clock to treat obesity Results reveal that fasting glucose levels did not change after 2–12 months of TRE in adults with obesity, even when participants achieved 5% weight loss.

2. sciencedirect.com sciencedirect.com/science/article/pii/S2589004224002219

Time-restricted eating improves health because of energy ... The results showed that TRE led to modest weight loss, lower waist circumference and energy deficits. TRE also improved body mass index, fat ...

3. jamanetwork.com jamanetwork.com/journals/jamainternalmedicine/fullarticle/2794819

Effectiveness of Early Time-Restricted Eating for Weight ... Studies have shown that TRE prevents and reverses diet-induced obesity in rodents. Adults who adhere to TRE typically lose 1% to 4% of their ...

4. mdpi.com mdpi.com/2072-6643/16/19/3390

The Effects of Time-Restricted Eating on Fat Loss in Adults ... It is observed that TRE with eating windows of 6 to 8 h, either alone or combined with caloric restriction, may be most effective for reducing body fat and ...

5. academic.oup.com academic.oup.com/edrv/article/43/2/405/6371193

Time-restricted Eating for the Prevention and Management of ... Pilot human intervention studies have reported promising results in reducing the risk for obesity, diabetes, and cardiovascular diseases. Epidemiological ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC5388543/

Fasting, circadian rhythms, and time restricted feeding in ... Time-restricted feeding is a daily eating pattern in which all nutrient intake occurs within a few hours (usually ≤12h) everyday, with no overt attempt to alter ...

7. sciencedirect.com sciencedirect.com/science/article/pii/S1550413123004540

Time-restricted eating: Watching the clock to treat obesity In participants with obesity, time-restricted eating results in 3%–5% weight loss over 2–12 months, versus controls. Reductions in body weight ...

8. jamanetwork.com jamanetwork.com/journals/jamainternalmedicine/fullarticle/2771095

Effects of Time-Restricted Eating on Weight Loss and Other ... This randomized clinical trial examines the effect of 16:8-hour time-restricted eating on weight loss and metabolic risk markers.