Effects of Time-Restricted Fasting on the Postprandial Glycemic Responses

Fudan University

Status: Active, not recruiting

Conditions: Healthy

Treatments: Behavioral: Consumption of lunch and dinner, with no breakfast; Behavioral: Consumption of breakfast and lunch, with no dinner

Study type: Interventional

Funder types: Other

Identifiers

NCT05913635

21PJD005

Details and patient eligibility

About

The goal of this clinical trial is to investigate whether fasting timing has a significant effect on postprandial glycemic responses in healthy adults. The main questions it aims to answer are:

1. Whether fasting timing has a significant effect on postprandial insulin actions and plasma glucose concentration.
2. Whether fasting timing could modulate the glycemic metabolome and circadian rhythms in healthy individuals.

Participants will get the two interventions:

No-dinner: breakfast at 7.30 a.m., lunch at 1.00 p.m. and no dinner; No-breakfast: no breakfast, lunch at 1.00 p.m. and dinner at 8.00 p.m.

Full description

A randomized, crossover study design is used with 2 intervention days and a 6-day washout period, to evaluate the effects of early and late fasting on postprandial glucose responses in healthy adults. Randomization was performed by the Fudan staff with a block size of 2 using a balanced design using computer-executed software. The primary endpoint is the fasting and postprandial blood glucose, insulin, and continuous glucose monitoring after fasting. Secondary endpoints include postprandial blood lipids, clock gene expressions in peripheral blood cells, and non-targeted postprandial plasma metabolome. The 2 intervention days include a no-breakfast day and a no-dinner day. The diets before, during, and after the intervention day was designed according to Dietary Guidelines for Chinese Residents (2022), and the energy distribution of three meals is 1:1:1, with the energy percentage of carbohydrate, protein, and fat being 55%, 15%, and 30%, respectively. The time of breakfast, lunch, and dinner is 7.30 a.m., 1.00 p.m., and 8.00 p.m., respectively. All participants are instructed to follow their natural dietary plans in the wash-out period, and the food intakes and sleep circle were recorded by a modified food frequency questionnaire (FFQ).

Enrollment: 36 patients

Sex: All

Ages: 18 to 40 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

1. Both men and women are eligible.
2. Age: 18-40 years old.
3. Healthy adults: no history of diabetes mellitus, no use of hypoglycemic drugs, no insulin injection.
4. All participants have a good sleep circle, with no somnipathy.

Exclusion criteria

1. Severe mental illness or other major medical comorbidities and autoimmune diseases (e.g., chronic renal failure, cardiovascular diseases, or cancer)
2. Skipping breakfast or dinner more than 10 times within 6 months.
3. Following a special diet, currently on weight loss medication, using sleeping medications.
4. Pregnancy or to be pregnant.

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Single Blind

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36 participants in 2 patient groups

No-breakfast

Experimental group

Description:

One-day meal plan with no breakfast. The dietary plan has been developed according to the Dietary Guidelines for Chinese Residents (2022), and the energy distribution of the two meals (lunch and dinner) is 1:1, with the energy percentage of carbohydrates, proteins, and fats being 55%, 15%, and 30%, respectively. The total daily calorie intake has been calculated based on the gender difference of the participants. Since the recommended daily calorie intake for males is 2000 kcal while for females it is 1600 kcal, each meal for males is designed to provide 667 kcal calories, comprising 92g carbohydrates, 22g fat, and 25g protein; each meal for females is designed to provide 533 kcal calories, comprising 73g carbohydrates, 18g fat, and 20g protein. The carbohydrates are sourced from buckwheat flour and mixed grain rice, which create similar glycemic indexes for each meal. Additionally, the one-day meal for both males and females includes 450g of vegetables and 320g of fruits.

Treatment:

Behavioral: Consumption of lunch and dinner, with no breakfast

No-dinner

Experimental group

Description:

One-day meal plan with no dinner. The dietary plan has been developed according to the Dietary Guidelines for Chinese Residents (2022), and the energy distribution of the two meals (breakfast and lunch) is 1:1, with the energy percentage of carbohydrates, proteins, and fats being 55%, 15%, and 30%, respectively. The total daily calorie intake has been calculated based on the gender difference of the participants. Since the recommended daily calorie intake for males is 2000 kcal while for females it is 1600 kcal, each meal for males is designed to provide 667 kcal calories, comprising 92g carbohydrates, 22g fat, and 25g protein; each meal for females is designed to provide 533 kcal calories, comprising 73g carbohydrates, 18g fat, and 20g protein. The carbohydrates are sourced from buckwheat flour and mixed grain rice, which create similar glycemic indexes for each meal. Additionally, the one-day meal for both males and females includes 450g of vegetables and 320g of fruits.

Treatment:

Behavioral: Consumption of breakfast and lunch, with no dinner