UMIN-ICDS Clinical Trial

Public title

Differences in fat and carbohydrate utilization after a high-fat meal across menstrual cycle phases

Acronym

Menstrual cycle and postprandial substrate oxidation

Scientific Title

The Effect of Menstrual Cycle on Metabolic Flexibility after High-Fat Meal Intake

Scientific Title:Acronym

Menstrual cycle and substrate oxidation after a high-fat meal

Region

Japan

Condition

Physiological variation in postprandial substrate oxidation across the menstrual cycle

Classification by specialty

Not applicable

Adult

Classification by malignancy

Others

Genomic information

NO

Narrative objectives1

This study aims to compare substrate oxidation responses to a high-fat meal between the follicular and luteal phases in healthy young women with regular menstrual cycles. Each participant receives the same high-fat meal in both phases, with respiratory gas exchange and circulating metabolic markers assessed in the fasting state and for 3 hours after the meal. Serum sex hormones and fasting fatty acid-binding protein 4 (FABP4) are also measured to characterize metabolic variation across the menstrual cycle.

Basic objectives2

Others

Basic objectives -Others

To assess physiological variation in substrate oxidation and circulating metabolic markers after a high-fat meal across the menstrual cycle.

Trial characteristics_1

Exploratory

Trial characteristics_2

Explanatory

Developmental phase

Not applicable

Primary outcomes

Change in respiratory exchange ratio (RER) from fasting values after a high-fat meal. Oxygen consumption and carbon dioxide production are measured by indirect calorimetry in the fasting state and at 1, 2, and 3 hours after the meal during the follicular and luteal phases. RER responses are compared between phases.

Key secondary outcomes

Fat oxidation, carbohydrate oxidation, energy expenditure, free fatty acids, insulin, and glucose in the fasting state and at 1, 2, and 3 hours after the meal; and fasting serum FABP4, estradiol, and progesterone. These measures are compared between the follicular and luteal phases.

Study type

Interventional

Basic design

Single arm

Randomization

Non-randomized

Randomization unit

Blinding

Open -no one is blinded

Control

Self control

Stratification

Dynamic allocation

Institution consideration

Blocking

Concealment

No. of arms

1

Purpose of intervention

Prevention

Type of intervention

Food

Interventions/Control_1

Each participant undergoes a high-fat meal test during the follicular and luteal phases. Participants fast for 12 hours, with water permitted. A high-fat meal of identical composition and quantity is provided to all participants (approximately 610 kcal, with approximately 61% of energy from fat) and consumed within 15 minutes under supervision. Respiratory gas exchange and blood samples are obtained in the fasting state and at 1, 2, and 3 hours after the meal. Participants remain seated at rest between measurements. Menstrual phase is verified using menstrual dates, ovulation testing, and serum sex hormone concentrations.

Interventions/Control_2

Interventions/Control_3

Interventions/Control_4

Interventions/Control_5

Interventions/Control_6

Interventions/Control_7

Interventions/Control_8

Interventions/Control_9

Interventions/Control_10

Age-lower limit

18

years-old

<=

Age-upper limit

29

years-old

>=

Gender

Female

Key inclusion criteria

Healthy women aged 18-29 years.
Regular menstrual cycles of 25-38 days.
No habitual exercise.
Written informed consent after receiving an explanation of the study.

Key exclusion criteria

Menstrual cycles outside the range of 25-38 days.
Current smoking.
BMI below 18.5 kg/m2.
Use of low-dose oral contraceptives within the previous 6 months.
Metabolic or hormonal disorders.
A medical condition requiring ongoing treatment or current pregnancy.
Food allergies or other conditions that preclude consumption of the test meal.
Participation in another clinical trial at enrollment.
Any other reason judged by the principal investigator to make participation inappropriate.

Target sample size

15

Name of lead principal investigator

1st name	Akira
Middle name
Last name	Ishikawa

Organization

Tokyo Kasei University

Division name

Faculty of Nutrition

Zip code

173-0003

Address

1-18-1 Kaga, Itabashi Tokyo, JAPAN

TEL

03-3961-7563

Email

aishikawapan@gmail.com

Name of contact person

1st name	Akira
Middle name
Last name	Ishikawa

Organization

Tokyo Kasei University

Division name

Faculty of Nutrition

Zip code

173-0003

Address

1-18-1 Kaga, Itabashi Tokyo, JAPAN

TEL

03-3961-7563

Homepage URL

Email

aishikawapan@gmail.com

Institute

Tokyo Kasei University

Institute

Department

Personal name

Organization

Institute for Food and Health Science, Yazuya Co., Ltd.

Organization

Division

Category of Funding Organization

Profit organization

Nationality of Funding Organization

Japan

Co-sponsor

Nippon Sport Science University

Name of secondary funder(s)

Organization

Research Ethics Committee, Faculty of Home Economics, Tokyo Kasei University

Address

1-18-1 Kaga, Itabashi Tokyo, JAPAN

Tel

03-3961-1934

Email

kaken@tokyo-kasei.ac.jp

Secondary IDs

NO

Study ID_1

Org. issuing International ID_1

Study ID_2

Org. issuing International ID_2

IND to MHLW

Institutions

日本体育大学（東京都）

Date of disclosure of the study information

2026

Year

11

Month

10

Day

URL releasing protocol

Publication of results

Published

URL related to results and publications

https://yazuken.jp/subsidy/dac121dbda95b2246d3818daf0d3d8e054c8fc5b.pdf

Number of participants that the trial has enrolled

12

Results

Nine participants were analyzed. Postprandial respiratory exchange ratio and fat oxidation responses did not differ significantly between the follicular and luteal phases. Exploratory analysis showed a positive correlation between luteal progesterone concentrations and the follicular-minus-luteal difference in fat oxidation responses (r=0.685, p=0.042).

Results date posted

2026

Year

11

Month

10

Day

Results Delayed

Results Delay Reason

Date of the first journal publication of results

Baseline Characteristics

Nine healthy women with regular menstrual cycles and no habitual exercise were included in the analysis. Age was 23.7 +/- 2.4 years, and height was 157.6 +/- 9.0 cm. Body mass was 57.0 +/- 10.0 kg in the follicular phase and 56.7 +/- 10.0 kg in the luteal phase. Values are mean +/- standard deviation. The same participants were assessed in both phases.

Participant flow

Written informed consent was obtained from 12 participants. Three participants were not included in the analysis: one because of low-dose oral contraceptive use, one because of emergency contraceptive use, and one for personal reasons. Nine participants with measurements from both the follicular and luteal phases were analyzed.

Adverse events

No adverse events were reported.

Outcome measures

Nine participants were analyzed. Values are mean +/- standard deviation and are presented in the order of follicular and luteal phases unless otherwise specified. Postprandial responses of respiratory gas-derived measures were calculated as the mean value at 1, 2, and 3 hours after the meal minus the fasting value.

The respiratory exchange ratio response was -0.0056 +/- 0.0344 and 0.0082 +/- 0.0379. The paired t-test showed no significant difference (p=0.339). The mean follicular-minus-luteal difference was -0.0138 (95% CI: -0.0451 to 0.0175).

The fat oxidation response was 11.89 +/- 12.89 and 12.36 +/- 12.90 mg/min (p=0.832). The mean difference was -0.47 mg/min (95% CI: -5.44 to 4.50). The carbohydrate oxidation response was 2.80 +/- 36.14 and 19.79 +/- 34.23 mg/min (p=0.312). The energy expenditure response was 0.123 +/- 0.119 and 0.191 +/- 0.080 kcal/min (p=0.265). Energy expenditure was calculated from oxygen consumption and carbon dioxide production using the Weir equation.

Fasting serum FABP4 concentrations were 24.84 +/- 14.97 and 21.51 +/- 4.82 ng/mL (p=0.416). Serum estradiol concentrations were 43.4 +/- 26.7 and 180.6 +/- 59.5 pg/mL, and serum progesterone concentrations were 0.24 +/- 0.12 and 14.90 +/- 4.21 ng/mL. Both hormones were higher in the luteal phase (p<0.001). The above p-values were obtained using paired t-tests.

Blood glucose concentrations at 1, 2, and 3 hours after the meal were 77.4 +/- 11.2, 78.9 +/- 8.2, and 83.0 +/- 8.8 mg/dL in the follicular phase and 79.8 +/- 8.4, 80.9 +/- 10.1, and 86.6 +/- 6.6 mg/dL in the luteal phase. The longitudinal analyses described in the research report showed no significant phase differences in changes from fasting concentrations of free fatty acids, insulin, or glucose.

An exploratory analysis conducted after data collection showed a positive correlation between luteal serum progesterone concentrations and the follicular-minus-luteal difference in the fat oxidation response without normalization to body mass (Pearson's r=0.685, p=0.042). Reported p-values are unadjusted for multiple comparisons.

Plan to share IPD

No.

IPD sharing Plan description

There is no plan to share individual participant data.

Recruitment status

Main results already published

Date of protocol fixation

2024

Year

07

Month

13

Day

Date of IRB

2024

Year

08

Month

22

Day

Anticipated trial start date

2025

Year

04

Month

30

Day

Last follow-up date

2025

Year

11

Month

24

Day

Date of closure to data entry

Date trial data considered complete

Date analysis concluded

Other related information

The study was approved by the Research Ethics Committee of the Faculty of Home Economics, Tokyo Kasei University (approval number: ItaE2024-13; August 22, 2024), and the Research Ethics Committee of Nippon Sport Science University (approval number: 024-H110; September 20, 2024).

The study was not prospectively registered because the investigators did not recognize the need for public trial registration at study initiation. This registration is retrospective and follows completion of data collection.

The original protocol emphasized changes in respiratory quotient after a high-fat meal but did not explicitly define a hierarchy of primary and secondary outcomes. Outcomes in this registration have been organized based on the original protocol. The analysis of the association between luteal progesterone concentrations and the follicular-minus-luteal difference in fat oxidation responses was conceived after completion of data collection and is exploratory rather than prespecified.

Registered date

2026

Year

11

Month

10

Day

Last modified on

2026

Year

11

Month

10

Day

Link to view the page

Value
https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000072757