Meal Timing for Obesity

(CM Trial)

Recruiting at 1 trial location

Overseen By Diane Hawkins

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: Columbia University

Must not be taking: Antidepressants, Psychoactive, Hypnotic, others

Disqualifiers: Sleep disorders, Psychiatric disorders, Smoking, others

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

Compensation: Varies

Number of Visits: 6

42 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores how meal timing affects weight regulation and energy balance, particularly when meals and sleep are misaligned. Participants will eat meals either in sync with their sleep schedule or with a 4-hour delay to observe the impact on the brain's response to food. It is ideal for individuals with a body mass index (BMI) between 20 and 34.9 who typically sleep at least 7 hours a night and maintain a regular eating schedule. The study aims to provide guidance for those with irregular sleep patterns, such as shift workers or frequent travelers. As an unphased study, it offers participants the chance to contribute to valuable research that could enhance lifestyle recommendations for many.

Will I have to stop taking my current medications?

The trial requires that participants do not take certain medications, such as psychoactive or hypnotic medications, chronic pain or anti-inflammatory medications, and beta blockers. If you are taking any of these, you may need to stop before joining the trial.

What prior data suggests that this meal timing protocol is safe for participants?

Studies have shown that meal timing can affect weight and health. Research suggests that eating later in the day might hinder weight loss, while eating earlier might assist it. Other studies have found that people who ate all their meals within an eight-hour period lost weight and improved some health measures.

In terms of safety, adjusting meal timing is generally manageable. It involves changing when meals are eaten, not what or how much. No reports of serious side effects from altering meal times exist. Therefore, for those considering joining this study, current evidence suggests that this approach is safe. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it's exploring how meal timing might affect obesity, which is a fresh angle compared to traditional treatments like diet adjustments, exercise, and medication. Unlike those standard approaches, this study looks at aligning meals with our body's natural clock, or circadian rhythm, to see if it impacts weight differently. One group eats with their natural sleep cycle, while another group delays meals by four hours. This could reveal if simply changing when we eat can help manage weight, offering a potentially simple and non-invasive method to tackle obesity.

What evidence suggests that meal timing is effective for obesity?

Research has shown that meal timing can affect weight and energy use. Eating at times that don't align with the body's natural clock may increase the risk of weight gain and health issues like type 2 diabetes. This trial will compare two meal timing strategies: the "Circadian alignment" arm, with meals from 9 AM to 7 PM, and the "Circadian misalignment" arm, with meals delayed by 4 hours, from 1 PM to 11 PM. Studies suggest that eating earlier in the day, when the body aligns with its natural rhythm, can boost metabolism and aid weight loss. Conversely, eating late at night, especially before bed, may lead to weight gain as the body is more likely to store food as fat. Thus, aligning meals with the body's natural schedule might help manage weight. ^{6 7 8 9 10}

Who Is on the Research Team?

Marie-Pierre St-Onge, PhD

Principal Investigator

Columbia University

Are You a Good Fit for This Trial?

This trial is for adults with obesity (BMI of 25-34.9) who usually sleep at least 7 hours, starting at or before 4 AM, and eat within an hour of waking up. It's open to all races and ethnicities. People can't join if they have sleep disorders, severe insomnia, psychiatric conditions, recent significant weight changes, are pregnant or post-partum within a year, have high alcohol intake or substance abuse history.

Inclusion Criteria

Body mass index 25-34.9 kg/m2

Average sleep duration ≥7 hour/night, assessed during 2-week screening period

All racial and ethnic groups

Exclusion Criteria

Current or past psychiatric disorder, including eating disorders and seasonal affective disorder

Any psychological or psychiatric disorder deemed to interfere with study outcomes

Smoking (currently smoking any cigarettes or using tobacco products, e-cigarettes and vapes, or ex-smokers <3 years)

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Circadian Alignment Phase

Participants consume meals aligned to the sleep episode, from 9 AM to 7 PM

2 weeks

Measurements taken after 3 and 14 days

Circadian Misalignment Phase

Participants consume meals misaligned to the sleep episode, from 1 PM to 11 PM

2 weeks

Measurements taken after 3 and 14 days

Free-living Period

Participants follow prescribed meal times for each phase in a free-living environment

4 weeks

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Meal times

Trial Overview The study investigates how the timing of meals and sleep affects body weight regulation without changing sleep duration. It aims to provide guidance on meal and sleep scheduling that could benefit shift workers or those experiencing jetlag.

How Is the Trial Designed?

Group I: Circadian misalignment Experimental Treatment 1 Intervention

Meals in this condition will be delayed by 4 hours relative to the circadian alignment condition. Food intake during this period will be from 1 PM to 11 PM.

Group II: Circadian alignment Active Control 1 Intervention

Meals in this condition will be aligned to the sleep episode. Food intake during this period will be from 9 AM to 7 PM.

Who Is Running the Clinical Trial?

Columbia University

Lead Sponsor

Trials

1,529

Recruited

2,832,000+

NYU Langone Health

Collaborator

Trials

1,431

Recruited

838,000+

Published Research Related to This Trial

In a study of 3,658 Korean men aged 18 to 60, disruptions in circadian rhythm, such as irregular breakfast frequency and inadequate sleep duration, were linked to a higher risk of general obesity, with adjusted odds ratios indicating a significant increase in risk for those with one or more disrupting factors.

Men with two or more circadian rhythm disturbances had an even greater risk for both general (aOR 1.62) and abdominal obesity (aOR 1.70), highlighting the importance of maintaining a regular circadian rhythm for weight management.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Association between misalignment of circadian rhythm and obesity in Korean men: Sixth Korea National Health and Nutrition Examination Survey. Kim, HJ., Choi, S., Kim, K., et al.[2021]

An 8-week daytime eating schedule significantly promotes weight loss and improves energy metabolism and insulin sensitivity in healthy adults with a BMI of 19-27 kg/m2, compared to a delayed eating schedule.

Participants on the delayed eating schedule experienced increases in body weight, insulin resistance, and triglycerides, highlighting the negative metabolic effects associated with eating later in the day.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Prolonged, Controlled Daytime versus Delayed Eating Impacts Weight and Metabolism. Allison, KC., Hopkins, CM., Ruggieri, M., et al.[2022]

In a study of 85 adults with overweight or obesity, the median eating window was found to be over 14 hours, indicating prolonged eating patterns throughout the day.

Participants had significantly shorter eating windows on weekends compared to weekdays, suggesting that eating timing may vary based on daily routines, which could impact weight management strategies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Temporal Eating Patterns and Eating Windows among Adults with Overweight or Obesity. Popp, CJ., Curran, M., Wang, C., et al.[2022]

In a 12-week study involving 91 overweight/obese non-shift workers, those who achieved a satisfactory weight loss (≥3% body weight) had a significantly higher intake of protein earlier in the day and reduced fat intake later in the day, indicating that timing and composition of meals are crucial for weight loss success.

Participants with satisfactory weight loss also had earlier last meal times and shorter eating windows, along with a notable reduction in night eating syndrome scores, suggesting that chrono-nutrition practices can effectively support weight reduction efforts.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Improvement in chrono-nutrition is associated with robust weight loss outcomes: An extension of the feasibility study. Mazri, FH., Manaf, ZA., Shahar, S., et al.[2023]

Eating earlier in the day may help with weight management and metabolic health, but the evidence is inconsistent, highlighting the need for more rigorous and longer studies.

Understanding the circadian mechanisms behind how eating timing affects metabolism could lead to better medical interventions for obesity and metabolic diseases, and help shape clinical guidelines for eating schedules.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Timing of eating in adults across the weight spectrum: Metabolic factors and potential circadian mechanisms. Allison, KC., Goel, N.[2023]

Research indicates that the timing of food intake is significantly associated with obesity and metabolic health, suggesting that when we eat may be as important as what and how much we eat.

Eating earlier in the day is linked to benefits such as reduced weight gain and lower risks of hyperglycemia and diabetes, highlighting meal timing as a potential target for obesity prevention and treatment strategies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Timing of food intake: Sounding the alarm about metabolic impairments? A systematic review. Beccuti, G., Monagheddu, C., Evangelista, A., et al.[2018]

Current evidence suggests that increasing the fasting period between meals may be more beneficial for weight control and metabolic health than the traditional approach of eating multiple small meals throughout the day.

This review highlights the importance of meal timing and frequency in managing body weight and metabolic health, indicating that more research is needed to fully understand these effects under different energy balance conditions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Metabolic impacts of altering meal frequency and timing - Does when we eat matter? Hutchison, AT., Heilbronn, LK.[2017]

In a study of 81 adults with obesity, those with a morning chronotype (MC) spent significantly more time eating lunch and dinner compared to evening chronotype (EC) individuals, who ate faster.

The faster eating speed of EC individuals may contribute to their higher risk of obesity-related cardiometabolic diseases, highlighting the importance of chronotype in dietary habits.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

How Fast Do "Owls" and "Larks" Eat? Verde, L., Docimo, A., Chirico, G., et al.[2023]

A systematic review of 34 studies found that irregular eating patterns, characterized by between-day variability in meal frequency, are linked to negative health outcomes such as higher body weight and poorer cognitive performance.

Current methods for measuring meal pattern variability are inconsistent and often based on assumptions, highlighting the need for more rigorous dietary intervention studies to establish clear causal relationships.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A systematic review of associations between day-to-day variability in meal pattern and body weight, components of the metabolic syndrome and cognitive function. Ali, MA., Macdonald, IA., Taylor, MA.[2023]

In a study of 49 adults undergoing colon cancer screening, those with inconsistent eating times had a significantly higher Body Mass Index (BMI) compared to those with consistent eating habits, indicating a potential link between eating patterns and obesity.

Specifically, individuals who ate inconsistently and late had the highest average BMI, suggesting that irregular meal timing may contribute to metabolic dysregulation and obesity risk.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Inconsistent eating time is associated with obesity: A prospective study. Adnan, D., Trinh, J., Bishehsari, F.[2022]

In a study of 637 women participating in weight loss programs, both meal time regularity (MTR) and calorie intake regularity (CIR) were found to significantly contribute to weight loss, indicating that consistent meal timing and calorie amounts can enhance weight loss efforts.

Subjects who maintained equal calorie intake at each meal lost more weight compared to those with irregular calorie consumption, suggesting that not just what you eat, but when and how consistently you eat can impact weight loss success.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The association between meal regularity and weight loss among women in commercial weight loss programs. Eom, H., Lee, D., Cho, Y., et al.[2022]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC7997809/

Circadian rhythms and meal timing: impact on energy balance ... Repeated disruption through mismatched timing of eating and sleeping has been shown to increase the risk of obesity, type 2 diabetes and ...

2. sciencedirect.com sciencedirect.com/science/article/abs/pii/S2405457723011890

Circadian misalignment in obesity: The role for time- ... Earlier ('circadian-aligned') eating was associated with greater diet-induced thermogenesis, and improved weight loss and glycaemic outcomes. Limited evidence ...

3. jhpn.biomedcentral.com jhpn.biomedcentral.com/articles/10.1186/s41043-025-01102-y

Circadian nutrition and obesity: timing as a nutritional strategy Eating during the biological night is misaligned with the circadian rhythm of metabolism, which favors nutrient storage over utilization.

4. nature.com nature.com/articles/s43856-025-01035-x

Meal timing trajectories in older adults and their ... The results support the hypothesis that maintaining consistent eating schedules, including breakfast times, could restore circadian rhythms in ...

5. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6893547/

Timing of Breakfast, Lunch, and Dinner. Effects on Obesity and ... In evening chronotypes who eat at night (during the two hours before sleep) the probability of being obese increases five times, while in morning chronotypes ...

6. mdpi.com mdpi.com/2072-6643/11/11/2624

Timing of Breakfast, Lunch, and Dinner. Effects on Obesity ... We found that eating the main meal late (after 3 p.m.), was predictive of difficulty in weight loss [9]. In addition, the distribution of energy intake across ...

7. nia.nih.gov nia.nih.gov/news/timeframe-8-hour-restricted-eating-irrelevant-weight-loss

Timeframe of 8-hour restricted eating irrelevant to weight loss Participants with obesity who engaged in any of three 8-hour, time-restricted eating schedules experienced weight loss and improvements in ...

8. jamanetwork.com jamanetwork.com/journals/jamanetworkopen/fullarticle/2825747

Meal Timing and Anthropometric and Metabolic Outcomes This systematic review and meta-analysis evaluates the association between meal timing strategies and anthropometric and metabolic outcomes.

9. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC11530941/

Meal Timing and Anthropometric and Metabolic Outcomes This systematic review and meta-analysis evaluates the association between meal timing strategies and anthropometric and metabolic outcomes.

10. sciencedirect.com sciencedirect.com/science/article/pii/S2161831322006433

Nutrition Targeting by Food Timing: Time-Related Dietary ... Reviewing literature published in the last 5 y reveals that these diets may improve risk factors associated with obesity and metabolic syndrome. However, each ...