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

Trial Summary

What is the purpose of this trial?

A randomized controlled trial to determine adherence, acceptability and safety of time restricted eating (TRE) in healthy, sedentary, free-living adults with obesity between the ages of 19-65 years when following 16:8 TRE for 8 weeks. This 9-week study includes a baseline week and 8 weeks of the intervention period. Participants are randomly assigned to the TRE or the non-fasting control group. The TRE group will consume calorie containing food and drink only over an 8 hour period and rest of the 16 hour would be fasting. Adherence to TRE and calorie intake are the primary outcomes. Motivators, facilitators and barriers to TRE, hunger and cravings levels, weight bias internalization, body composition (weight, body fat%, fat mass and muscle mass) , Healthy Eating Index (HEI) to assess diet quality, skin carotenoid levels, disordered eating risk, sleep quality, and perceptions of health and well-being are secondary outcomes.

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 data supports the effectiveness of the treatment Time-Restricted Eating for obesity?

Research shows that Time-Restricted Eating (TRE) can help reduce body weight and fat mass, while also improving heart health markers like blood pressure and cholesterol levels. These findings suggest that TRE is a promising approach for managing obesity and related health issues. ^{1 2 3 4 5}

Is time-restricted eating safe for people with obesity?

Research suggests that time-restricted eating, where food is consumed within a specific time window each day, is generally safe for people with obesity. Studies have shown no significant adverse effects on body image, blood counts, or eating patterns, indicating it can be a safe method to support weight loss. ^{1 5 6 7 8}

How is time-restricted eating different from other treatments for obesity?

Time-restricted eating is unique because it focuses on limiting the hours during which you eat each day, aligning with your body's natural circadian rhythms, rather than restricting specific foods or calories. This approach may help improve metabolic health and support weight loss by reinforcing the benefits of fasting and ketosis (a state where the body burns fat for energy). ^{1 5 8 9 10}

Eligibility Criteria

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

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)

Treatment Details

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.

Participant Groups

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+

Findings from Research

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]

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) 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]

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 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]

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]

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]

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 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]

References

1. China pubmed.ncbi.nlm.nih.gov

[Research progress on the application of time-restricted eating in adult obesity and related metabolic diseases]. [2022]

2. Russia (Federation) pubmed.ncbi.nlm.nih.gov

[Time-restricted eating as a novel strategy for treatment of obesity and it's comorbid conditions]. [2023]

3. Switzerland pubmed.ncbi.nlm.nih.gov

Beneficial Effects of Time-Restricted Eating on Metabolic Diseases: A Systemic Review and Meta-Analysis. [2021]

4. Switzerland 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. [2023]

5. England 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. [2021]

6. Canada pubmed.ncbi.nlm.nih.gov

Safety of 8-h time restricted feeding in adults with obesity. [2019]

7. United States 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. [2022]

8. United States pubmed.ncbi.nlm.nih.gov

Complex physiology and clinical implications of time-restricted eating. [2023]

9. England pubmed.ncbi.nlm.nih.gov

Effect of time restricted feeding on the gut microbiome in adults with obesity: A pilot study. [2022]

10. United States pubmed.ncbi.nlm.nih.gov

Time-restricted eating alters the 24-hour profile of adipose tissue transcriptome in men with obesity. [2023]