Time-Restricted Eating for Obesity

Overseen By Ashley Rosander, BS

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of California, San Diego

Must not be taking: Insulin, Anti-diabetics, Appetite suppressants, others

Disqualifiers: Diabetes, Pregnancy, Heart failure, others

Compensation: Varies

Number of Visits: Unknown

Duration: 12 weeks

61 Participants Needed

Trial Summary

What is the purpose of this trial?

In a randomized controlled trial, the investigators intend to measure the health impact of time-restricted eating (TRE) in obese patients (body mass index (BMI) ≥ 30 kg/m2), who habitually eat for more than 14 hours every day. Patients will be randomly assigned to a control group of behavioral nutritional counseling (standard of care) or the intervention group of behavioral nutrition counseling with the addition of adopting a 10-hour eating window for 12 weeks (TRE).

Do I need to stop my current medications for the trial?

The trial does not specify that you need to stop your current medications, but if you are on cardiovascular medications like statins or anti-hypertensive drugs, you cannot change the dose during the study.

What data supports the effectiveness of time-restricted eating as a treatment for obesity?

Research shows that time-restricted eating (TRE), a type of intermittent fasting, can help reduce body weight and fat mass while improving metabolic health, such as blood pressure and cholesterol levels. Studies indicate that TRE is as effective as traditional calorie-restricted diets for weight loss, making it a promising strategy for managing obesity. ^{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. A study found no significant changes in adverse events, body image, or disordered eating patterns over 12 weeks, indicating it can be a safe way to help with weight loss. ^{4 5 6 7 8}

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

Time-restricted eating (TRE) is unique because it focuses on limiting the hours during which you eat each day, rather than reducing the amount of food you consume. This approach can help restore natural body rhythms and improve metabolic health, offering a novel way to manage obesity compared to traditional calorie-reduction diets. ^{2 5 9 10 11}

Research Team

Michael J Wilkinson, MD

Principal Investigator

University of California, San Diego

Eligibility Criteria

Adults over 18 with obesity (BMI of 30-50), who eat for more than 14 hours a day and own a smartphone. They must not be on any weight-affecting meds, pregnant, or have various health conditions like heart failure or uncontrolled psychiatric disorders. Those on stable cardiovascular meds can join but can't change doses during the trial.

Inclusion Criteria

I am not changing my heart or cholesterol medication doses during the study.

Baseline eating window ≥ 14 hours/day

My BMI is between 30 and 50.

Exclusion Criteria

Pregnant or breast-feeding women

I have a diagnosed inflammatory or rheumatologic condition.

Active tobacco abuse or illicit drug use or history of treatment for alcohol abuse

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants are randomly assigned to either a control group receiving standard nutritional counseling or an intervention group with time-restricted eating for 12 weeks

12 weeks

Regular visits for counseling and monitoring

Follow-up

Participants are monitored for safety and effectiveness after treatment, including measurements of inflammation, body weight, and body composition

2 weeks

Treatment Details

Interventions

• Standard of Care
• Time Restricted Eating

Trial Overview The study is testing if limiting eating to a 10-hour window (Time-Restricted Eating) plus nutritional counseling affects obese adults' health differently compared to just nutritional counseling alone. Participants will follow their assigned eating plan for 12 weeks.

Participant Groups

Group I: TRE + SOC Experimental Treatment 1 Intervention

Participants in this arm will receive standard of care nutritional behavioral counseling and will implement a daily, self-selected, 10-hour window within which they must consume all calories. They will also be required to log their caloric intake through the use of a smartphone app

Group II: Standard of Care (SOC) Placebo Group 1 Intervention

Participants will receive standard of care nutritional behavioral counseling and will be required to log their caloric intake through the use of a smartphone app.

Who Is Running the Clinical Trial?

University of California, San Diego

Lead Sponsor

Trials

1,215

Recruited

1,593,000+

Salk Institute for Biological Studies

Collaborator

Trials

23

Recruited

2,200+

Findings from Research

Intermittent energy restriction (IER) strategies, such as intermittent fasting and time-restricted feeding, show similar effectiveness in weight loss compared to continuous energy restriction (CER) in adults with obesity, based on a review of randomized trials lasting at least 8 weeks.

Out of 11 studies analyzed, 9 found no significant differences in weight or body fat loss between IER and CER, suggesting that IER can be a viable alternative for obesity treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effectiveness of Intermittent Fasting and Time-Restricted Feeding Compared to Continuous Energy Restriction for Weight Loss. Rynders, CA., Thomas, EA., Zaman, A., et al.[2021]

Intermittent energy restriction (IER) was found to be a feasible and effective weight management strategy for adolescents aged 12-17 with obesity, leading to a significant reduction in BMI %95th percentile after 12 weeks (-5.6%) and maintained reductions at 26 weeks.

Participants reported IER as easy and pleasant to follow, indicating high acceptability, and the intervention also resulted in improvements in cardiovascular health markers, such as reduced carotid intima-media thickness and improved flow-mediated dilation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Intermittent Energy Restriction Is a Feasible, Effective, and Acceptable Intervention to Treat Adolescents with Obesity. Jebeile, H., Gow, ML., Lister, NB., 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]

Intermittent fasting (IF) may be an effective weight management strategy for overweight and obese adults, but its evidence base in humans is still limited, with only one published systematic review available.

Current guidelines from the National Institute for Health and Care Excellence (NICE) do not recommend very low calorie diets (VLCD) as a routine treatment for obesity, highlighting concerns about potential side effects and the sustainability of fasting approaches.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Intermittent fasting interventions for the treatment of overweight and obesity in adults aged 18 years and over: a systematic review protocol. Jane, L., Atkinson, G., Jaime, V., et al.[2022]

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 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]

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]

Time-restricted eating (TRE) is a feasible and safe intervention for individuals with overweight, obesity, prediabetes, or type 2 diabetes, with high retention rates of 95% for studies under 12 weeks and 89% for those 12 weeks or longer.

Participants generally adhered to TRE well, with median adherence rates of 89% for shorter studies and 81% for longer ones, although individual experiences varied, highlighting the need for support and flexibility in the approach.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Feasibility of time-restricted eating in individuals with overweight, obesity, prediabetes, or type 2 diabetes: A systematic scoping review. Termannsen, AD., Varming, A., van Elst, C., et al.[2023]

In a 12-week study involving 20 participants (17 women and 3 men), time-restricted eating (TRE) significantly reduced the eating window and led to weight loss, decreased fat mass, and reduced visceral fat compared to an unrestricted eating control group.

Participants in the TRE group experienced a 3.7% reduction in weight and an 11.1% reduction in visceral fat, demonstrating that TRE can be an effective strategy for weight management without changing physical activity or metabolic measures.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Time-Restricted Eating Effects on Body Composition and Metabolic Measures in Humans who are Overweight: A Feasibility Study. Chow, LS., Manoogian, ENC., Alvear, A., et al.[2020]

References

1. Switzerland pubmed.ncbi.nlm.nih.gov

Effectiveness of Intermittent Fasting and Time-Restricted Feeding Compared to Continuous Energy Restriction for Weight Loss. [2021]

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

Intermittent Energy Restriction Is a Feasible, Effective, and Acceptable Intervention to Treat Adolescents with Obesity. [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. Australia pubmed.ncbi.nlm.nih.gov

Intermittent fasting interventions for the treatment of overweight and obesity in adults aged 18 years and over: a systematic review protocol. [2022]

5. China pubmed.ncbi.nlm.nih.gov

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

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

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

7. England pubmed.ncbi.nlm.nih.gov

Watching, keeping and squeezing time to lose weight: Implications of time-restricted eating in daily life. [2021]

8. 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]

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

Feasibility of time-restricted eating in individuals with overweight, obesity, prediabetes, or type 2 diabetes: A systematic scoping review. [2023]

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

Time-Restricted Eating Effects on Body Composition and Metabolic Measures in Humans who are Overweight: A Feasibility Study. [2020]