Meal Timing for Blood Sugar Control

Overseen By Talia Hitt, MD/MPH/MSHP

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: Johns Hopkins University

Must not be taking: Insulin, Melatonin, others

Disqualifiers: Diabetes, Sleep disorders, Pregnancy, others

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

Compensation: Varies

Number of Visits: 12

70 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores how meal timing affects blood sugar control in young people. It examines whether eating meals in sync with one's natural sleep pattern (chronotype) influences sugar metabolism. Participants will undergo tests, including the timing of an Oral Glucose Tolerance Test (OGTT) and standardized meals, aligned or misaligned with their usual sleep schedule, to assess the impact on blood sugar and insulin levels. This trial may suit young people aged 17-23 who fall asleep after 2 am or before 11 pm, are post-puberty, and have a higher body weight (but not obese). As an unphased trial, this study offers a unique opportunity to contribute to understanding how meal timing can influence health.

Will I have to stop taking my current medications?

If you are taking medications that affect insulin sensitivity, glucose tolerance, or circadian rhythm, you may need to stop them to participate in this trial.

What prior data suggests that this study's methods are safe?

Research shows that both the timing of an oral glucose tolerance test (OGTT) and meal timing are generally manageable for participants. The OGTT, a common test to assess how the body processes sugar, involves drinking a sugary solution and measuring blood sugar levels before and after. Most participants tolerate this test well, though some may experience mild nausea after consuming the solution.

Regarding meal timing, studies suggest that eating meals at specific times can help manage blood sugar levels, particularly for individuals with type 2 diabetes. This approach has improved blood sugar control without major side effects. Overall, both timing strategies are considered safe for participants in this type of study. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it explores how meal timing can influence blood sugar control, which is a novel approach compared to traditional treatments like medications and lifestyle changes. This study specifically looks at how the timing of an oral glucose tolerance test (OGTT) and a standardized meal impacts individuals with different sleep patterns, or chronotypes. Unlike conventional methods that focus on medication or diet composition, this trial aims to understand the role of meal timing, potentially offering a simple yet effective strategy for managing blood sugar levels based on personal sleep habits.

What evidence suggests that this trial's treatments could be effective for blood sugar control?

This trial will compare the effects of meal timing and oral glucose tolerance test (OGTT) timing on blood sugar control. Research has shown that taking an OGTT at a time that aligns with one's natural sleep and wake cycle might improve the body's ability to handle sugar. Studies have found that individuals who perform well on this test typically have lower blood sugar levels and better overall health. Regarding meal timing, eating all meals within a specific time frame each day, known as time-restricted eating (TRE), can significantly lower blood sugar levels. In one study, participants who practiced TRE experienced a noticeable drop in both fasting and after-meal blood sugar levels. These findings suggest that timing meals and tests to fit the body's natural rhythm can help manage blood sugar more effectively. Participants in this trial will be grouped into different cohorts based on their sleep chronotype to assess these effects. ^{1 6 7 8 9}

Who Is on the Research Team?

Talia Hitt, MD/MPH/MSHP

Principal Investigator

Johns Hopkins University

Are You a Good Fit for This Trial?

This trial is for young individuals aged 17-23 with obesity, prediabetes, or diabetes. It's specifically designed to see how their body clock (chronotype) affects their blood sugar control when they take a glucose test or have their first meal of the day at different times.

Inclusion Criteria

Normal sleep duration (average >7 hours of sleep per night)

Social jetlag (difference between weekend and weekday sleep) of < 2 hours

I have gone through puberty.

Exclusion Criteria

Screening high risk for obstructive sleep apnea

I am not on medications that affect insulin sensitivity, glucose tolerance, or my body clock.

I have diabetes, a sleep disorder, a major illness, am pregnant, or have a genetic syndrome.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Randomized Cross-over

Participants undergo 2 OGTTs (aligned and mis-aligned with chronotype) to compare glucose tolerance and insulin sensitivity

11 days

Multiple visits for OGTTs on Day 4 and Day 11

Standardized Meal Testing

Participants undergo two standardized meals (aligned and mis-aligned with chronotype) while wearing continuous glucose monitoring

8 days

Continuous monitoring over 8 days

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Timing of OGTT
• Timing of Standardized Meal

Trial Overview The study is testing if timing an oral glucose tolerance test (OGTT) or the first meal of the day according to a person's natural sleep/wake cycle can affect insulin sensitivity and blood sugar levels in youth. Participants will experience tests both aligned and misaligned with their chronotype.

How Is the Trial Designed?

Group I: Cohort B - Non-late Chronotype first, then alternate Experimental Treatment 2 Interventions

Sleep onset before 11pm

Group II: Cohort A - Late Chronotype first, then alternate Experimental Treatment 2 Interventions

Sleep onset after 2am

Who Is Running the Clinical Trial?

Johns Hopkins University

Lead Sponsor

Trials

2,366

Recruited

15,160,000+

DexCom, Inc.

Industry Sponsor

Trials

151

Recruited

35,700+

Kevin Sayer

DexCom, Inc.

Chief Executive Officer since 2015

Bachelor’s and Master’s degrees in Accounting and Information Systems from Brigham Young University

Dr. Shelly Lane

DexCom, Inc.

Chief Medical Officer since 2023

MD from University of California, San Diego

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Collaborator

Trials

2,513

Recruited

4,366,000+

Lawson Wilkins Pediatric Endocrine Society

Collaborator

Trials

4

Recruited

190+

Published Research Related to This Trial

The study analyzed insulin levels during an oral glucose tolerance test (oGTT) in 101 adults using three different immunoassays, finding that all assays had comparable sensitivity and precision, but significant differences in insulin levels and sensitivity indices were observed with the AutoDELFIA method compared to the others.

It is important to use assay-specific reference intervals for interpreting insulin levels from oGTT, as factors like body mass index (BMI) and gender significantly influence insulin measurements.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Assay-dependent variability of serum insulin levels during oral glucose tolerance test: influence on reference intervals for insulin and on cut-off values for insulin sensitivity indices. Werner, M., Tönjes, A., Stumvoll, M., et al.[2016]

Delaying dinner by 1 hour or more significantly increases peak glucose levels and overall glucose fluctuations in healthy young adults, as measured by continuous glucose monitoring devices.

The study highlights the importance of regular meal timing, suggesting that irregular eating habits, like late dinners, can negatively impact glucose control.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Delayed dinnertime impairs glucose tolerance in healthy young adults. Nakamura, F., Shimba, Y., Toyonaga, S., et al.[2023]

In a study of 551 subjects, the shape of the plasma glucose response during an oral glucose tolerance test (OGTT) was found to vary based on glucose tolerance status and sex, with biphasic responses indicating better metabolic health compared to monophasic responses.

The study suggests that the 'shape index' of glucose response could serve as a valuable screening tool for assessing metabolic health and understanding genetic influences on glucose tolerance.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Assessing the shape of the glucose curve during an oral glucose tolerance test. Tschritter, O., Fritsche, A., Shirkavand, F., et al.[2022]

In a study of 4,768 young participants with type 1 diabetes, those who administered insulin before meals had significantly lower HbA1c levels (8.4%) compared to those who took it during or after meals (8.8%), indicating better glycemic control.

Participants who missed at least one insulin dose per week had higher HbA1c levels (9.8%) and were more likely to experience diabetic ketoacidosis (DKA) events (9%) compared to those who rarely missed doses, highlighting the importance of timely insulin administration.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Timing of Meal Insulin and Its Relation to Adherence to Therapy in Type 1 Diabetes. Datye, KA., Boyle, CT., Simmons, J., et al.[2020]

In a study of 20 well-controlled type 2 diabetes patients, skipping or eating the last meal of the day earlier significantly increased the duration of hypoglycemia, particularly during the night hours from 00:00 to 06:00.

The findings suggest that when adjusting basal insulin doses, it is crucial to consider the timing of the last meal to prevent nighttime hypoglycemia, which may go unnoticed by patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Omitting late-night eating may cause hypoglycemia in "well controlled" basal insulin-treated type 2 diabetes. King, AB., Clark, D.[2021]

Administering rapid-acting insulin analogues 15-20 minutes before meals can significantly improve postprandial glucose control in patients with Type 1 diabetes, reducing post-meal glucose levels by approximately 30%.

Taking insulin after meals increases the risk of postprandial hypoglycemia, highlighting the importance of timing in insulin administration for optimal diabetes management.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Optimal prandial timing of bolus insulin in diabetes management: a review. Slattery, D., Amiel, SA., Choudhary, P.[2022]

A study involving 46 hospitalized diabetic patients with vascular disease showed that a modified meal schedule significantly improved glucose control compared to a traditional feeding schedule, with higher percentages of patients maintaining normal glucose levels after meals.

The modified schedule resulted in better glucose management, with Group I achieving 91% normal levels at breakfast and 86% at snack time, compared to lower percentages in Group II, highlighting the importance of meal timing in diabetes management.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Diet and insulin. Best results with an adjusted schedule]. Martínez Martínez, A., Bonaventura Sans, C., Malet Bonet, M.[2015]

In a study of 377 Latin American patients with type 2 diabetes, exenatide taken before breakfast or lunch showed similar effectiveness in lowering HbA1c levels, with both regimens achieving significant reductions of approximately 1.2% and 1.1%, respectively.

The safety profile was comparable for both dosing schedules, with similar rates of hypoglycemia and nausea, indicating that either timing of exenatide administration is a safe option for improving glycemic control in patients who consume a small breakfast.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficacy and safety of exenatide administered before the two largest daily meals of Latin American patients with type 2 diabetes. Forti, A., Garcia, EG., Yu, MB., et al.[2022]

In a study involving 35 adults with type 1 diabetes, the fully closed loop (FCL) insulin delivery system with meal anticipation (FCL+) did not significantly improve post-meal blood sugar control compared to the standard FCL system, maintaining similar time in range (TIR) after meals.

Both FCL and FCL+ systems showed a similar or reduced risk of hypoglycemia, indicating that while meal anticipation did not enhance glycemic control, it also did not increase the risk of low blood sugar during meal delays.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Assessment of Meal Anticipation for Improving Fully Automated Insulin Delivery in Adults With Type 1 Diabetes. Garcia-Tirado, J., Colmegna, P., Villard, O., et al.[2023]

Administering rapid-acting insulin 15 minutes before meals significantly reduces post-meal blood sugar spikes in individuals with type 1 diabetes, as shown in a study with 10 participants.

This timing also allows for more time spent in the target glucose range (3.5-10.0 mmol/l) without increasing the risk of hypoglycemia, making it a safer option for managing blood sugar levels.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Premeal injection of rapid-acting insulin reduces postprandial glycemic excursions in type 1 diabetes. Luijf, YM., van Bon, AC., Hoekstra, JB., et al.[2022]

Gastric emptying (GE) significantly influences blood glucose levels during a 75-g oral glucose tolerance test (OGTT), with stronger correlations observed in individuals with impaired glucose tolerance (IGT) and type 2 diabetes (T2D) compared to those with normal glucose tolerance (NGT).

The study found that the relationship between GE and blood glucose levels varies over time, indicating that GE affects glycemic responses differently at 30, 60, and 120 minutes after glucose ingestion.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Relationships of Early And Late Glycemic Responses With Gastric Emptying During An Oral Glucose Tolerance Test. Marathe, CS., Horowitz, M., Trahair, LG., et al.[2015]

In a study of 100 patients with type 2 diabetes, exenatide was found to be more effective than Humalog Mix25 and oral antidiabetic drugs (OADs) in shifting the peak blood glucose time to an earlier point, which is a positive indicator of improved glucose metabolism.

Exenatide also significantly improved insulin secretion and insulin sensitivity, as evidenced by better insulinogenic index and homeostatic assessment of β-cell function compared to the other treatments, highlighting its superior efficacy in managing diabetes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Shift of Glucose Peak Time During Oral Glucose Tolerance Test is Associated with Changes in Insulin Secretion and Insulin Sensitivity After Therapy with Antidiabetic Drugs in Patients with Type 2 Diabetes. Jiang, Y., Cui, S., Zhang, R., et al.[2021]

Administering a rapid-acting insulin bolus 20 minutes before a meal significantly improves blood glucose control in adolescents and adults with type 1 diabetes, as shown by lower glycemic excursions and peak blood glucose levels.

In a study with 23 participants, the PRE timing of insulin delivery resulted in better post-meal glucose management compared to administering insulin immediately before or after the meal.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Timing of meal insulin boluses to achieve optimal postprandial glycemic control in patients with type 1 diabetes. Cobry, E., McFann, K., Messer, L., et al.[2022]

Citations

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Glucose Tolerance Test - StatPearls - NCBI Bookshelf A glucose tolerance test (GTT) is a procedure that determines whether a patient can use and store glucose normally.

2. sciencedirect.com sciencedirect.com/science/article/pii/S2666577824000844

A new classification method for gestational diabetes ... Our study investigates oral glucose tolerance test (OGTT) patterns in GDM women to pinpoint a high-risk subtype associated with adverse maternal and neonatal ...

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Oral glucose tolerance test clearance in type 2 diabetes ... Participants who cleared OGTT showed shorter diabetes duration, sustained weight loss and a reduction in HbA1c levels. Additionally, ...

4. diabetesjournals.org diabetesjournals.org/care/article/48/9/1581/163057/Real-Time-Continuous-Glucose-Monitoring-in

Real-Time Continuous Glucose Monitoring in Pregnancies ... We demonstrated a significantly higher %TIR using real-time CGM compared with CBG glucose monitoring among pregnant people with GDM. Studies are ...

5. uwmedicine.org uwmedicine.org/sites/stevie/files/2020-11/Gestational-Diabetes-Screening-Strategies%2C-Glycemic-Targets-and-Pharmacologic-Management-OB-Consensus-Conference.pdf

Gestational Diabetes: Given the costs and effort associated with a 3-hr oral glucose tolerance test, using a diagnostic threshold for the GCT may ultimately be more efficient and ...

6. mayoclinic.org mayoclinic.org/tests-procedures/glucose-tolerance-test/about/pac-20394296

Glucose tolerance test Testing usually is done between 24 and 28 weeks of pregnancy. Most often, screening includes a two-step process.

7. diabetesjournals.org diabetesjournals.org/care/article/47/Supplement_1/S20/153954/2-Diagnosis-and-Classification-of-Diabetes

2. Diagnosis and Classification of Diabetes: Standards of Care ... Diabetes can be diagnosed by demonstrating increased concentrations of glucose in venous plasma or increased A1C in the blood.

8. nejm.org nejm.org/doi/full/10.1056/NEJMoa2214956

Treatment of Gestational Diabetes Mellitus Diagnosed ... Immediate treatment of gestational diabetes before 20 weeks' gestation led to a modestly lower incidence of a composite of adverse neonatal outcomes than no ...

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101200: Glucose Tolerance Test (GTT), Two-hour (Oral ... Patient should be instructed not to eat or drink anything except water for at least eight hours and not more than 14 hours before the test. Patients should also ...