The Role of Estradiol and Progesterone on Appetite Regulation and Energy Balance (E2 & P4 in EB)

The goal of this study is to determine if estradiol and progesterone are involved in appetite regulation and energy balance. The study aims to complete a 13 day randomized controlled trial (RCT) where oral supplementation of estradiol only, progesterone only, a combination of each, or a placebo in young males will be provided. During the supplementation period, participants will complete two in-lab sessions where they will complete an acute bout of high-intensity interval training or a period of seated rest (completed on separate days by each participant) and have blood samples and perceptions of appetite measured taken over the course of the in-lab sessions. At the end of each session participants will consume an ad-libitum meal and participants will also track free-living energy intake and wear a thigh-worn accelerometer to measure energy expenditure for three days (day before, day of, and day after) each in-lab session.

Study Overview

• Status: Recruiting
• Conditions: Energy Balance; Physiology - Regulation of Appetite and Food Intake
• Intervention / Treatment: Drug: Placebo Comparator; Drug: Estradiol Only; Drug: Progesterone Only; Drug: Estradiol and Progesterone Combination

Detailed Description

The purpose of this study is to further elucidate the individual and combined effects of estradiol and progesterone on appetite-regulating hormones, perceptions of appetite, energy intake, and energy expenditure over a 13 day supplementation period using a randomized controlled trial (RCT) model in males who will be supplemented with each hormone. Sixty healthy, recreationally active male participants will be randomized into one of four possible groups: placebo (PLA; 400 milligrams (mg) per day glucose polymer), estradiol only (E; 1 mg per day for 2 days & 2 mg per day of estradiol for 11 days + 300 mg Polycose), progesterone only (P; Prometrium, 100 mg per day), or combined estradiol and progesterone (E+P; 1 mg per day for 2 days & 2 mg per day of estradiol for 11 days + 300 mg Polycose for estradiol and 100 mg per day of Prometrium) for a total of ~15 per group. Participants will be provided enough daily dose of each treatment dependent on randomization for a total of 13 days and will be instructed to take each supplement orally at the same time each day for the entirety of the intervention. Participants will report to the lab on the 7th day, where they will be fed a standardized meal and then complete either an acute bout of high-intensity interval training (HIIT; 1 minute on, 1 minute off at 90% HRmax) or a period of seated rest (CTRL). Participants will return on day 12 to complete either the HIIT or CTRL session in an identical manner (whichever was not completed on day 7). Blood samples to measure appetite-regulating hormones and perceptions of appetite will be completed pre-exercise, 0-, 30-, 60-, and 120-minutes post-HIIT and CTRL. While participants are receiving the 13 day treatment, free-living energy intake will be assessed for a 3 day period (day before, day of and day after both in lab visits (HIIT/CTRL; days 6-8 and days 11-13) using the Keenoa® mobile application, and energy expenditure will be measured via thigh-worn accelerometers for the same 3 day periods. An ad libitum meal will also be provided following the HIIT and CTRL sessions.

We anticipate publishing this RCT in two separate manuscripts. Manuscript #1 will focus on the potential effects on the appetite-regulating hormones (acylated ghrelin, GLP-1, CCK) and perceptions of appetite. Manuscript #2 will focus on potential effects on energy balance from the measures of energy intake (including free-living and ad-libitum meal intake) and energy expenditure.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jessica Tucker, MKin, PhD Candidate; Phone Number: 4919 519-884-1970; Email: tuck5010@mylaurier.ca

Study Locations

• Canada
  • Ontario
    • Waterloo, Ontario, Canada, N2L 3C5
      • Recruiting
      • Energy Metabolism Research Laboratory
      • Contact: Jessica Tucker, MKin, PhD Candidate; Phone Number: 4919 519-884-1970; Email: tuck5010@mylaurier.ca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• ages 18-30 years
• deemed healthy using Canadian Society for Exercise Physiology Get Active Questionnaire (CSEP-GAQ)
• non-smoking

Exclusion Criteria:

• failure to meet inclusion criteria

• contraindications to exercise as indicated by the (CSEP-GAQ)

  • hypersensitivity or allergy to estradiol, progesterone, cellulose, or capsule components
  • having been diagnosed with any metabolic disease (ie. diabetes, metabolic syndrome) or current diagnosis of overweight/obesity (BMI > 30.0)
  • personal of family history of stroke or thrombotic (blood clot) disease, blood clot disorder, venous or arterial thromboembolic disease, or any possible blood clotting disease
  • currently taking anticoagulants, antidiabetic medications, cyclosporine, antihypertensives, and CYP3A4 inducers or inhibitors (e.g., rifampin, ketoconazole, St. John's Wort)
  • known liver dysfunction or liver disease
  • history of ophthalmic vascular disease
  • hormone-dependent malignancies or previous diagnosis of cancer
  • recent major surgery (within ~6 months)
  • prolonged use of a cast or presence of immobility deeming inability to exercise, diagnosis of inflammatory disorders (ie. rheumatoid arthritis, celiac disease, inflammatory bowel disease)
  • history of sensitivity to or extreme nausea/vomiting or any gastrointestinal disorder
  • diagnosis of mental health or mood disorder
  • presence of abnormal eating behaviours as assessed by the Food Cravings State Questionnaire and the Three Factor Eating Questionnaire
  • diagnosed or presence of porphyria or classical migraines

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo Comparator; Participants will be randomized and placed into one of four groups. The placebo group will receive 400 milligrams (mg) per day of glucose polymer for 13 days total. The supplementation will be consumed orally at the same time every day for 13 days total. Participants will not complete more than one arm of the study.	Drug: Placebo Comparator; See description of intervention arm.
Experimental: Estradiol Only; Participants will receive 1 mg per day for 2 days and 2 mg per day of estradiol for 11 days + 300 mg polycose. The supplementation will be consumed orally at the same time every day for 13 days total. Participants will not complete more than one arm of the study.	Drug: Estradiol Only; See description of intervention arm.
Experimental: Progesterone Only; Participants will receive 100 mg per day of Prometrium (oral progesterone) for 13 days. The supplementation will be consumed orally at the same time every day for 13 days total. Participants will not complete more than one arm of the study.	Drug: Progesterone Only; See description of intervention arm.
Experimental: Estradiol and Progesterone Combo; Participants will receive 1 mg per day for 2 days and 2 mg per day estradiolfor 11 days + 300 mg polycose as well as 100 mg per day of Prometrium (oral progesterone). The supplementation will be consumed orally at the same time every day for 13 days total. Participants will not complete more than one arm of the study.	Drug: Estradiol and Progesterone Combination; See description of intervention arm.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Energy balance	Energy balance will be calculated as the difference between energy intake and energy expenditure (see below for description of energy intake and energy expenditure).	Energy balance will be measured using the data collected surrounding the exercise and no-exercise sessions (6 days total).
Acylated Ghrelin	Appetite-stimulating hormone acylated ghrelin to be measured via commercially available ELISA kits (pg/mL).	To be measured pre-exercise, 0 minutes post-exercise, 30 minutes post-exercise, 60 minutes post-exercise, and 120 minutes post-exercise.
Glucagon-like Peptide 1 (GLP-1)	Appetite-inhibiting hormone GLP-1 to be measured via commercially available ELISA kits (pmol/L).	To be measured pre-exercise, 0 minutes post-exercise, 30 minutes post-exercise, 60 minutes post-exercise, and 120 minutes post-exercise.
Cholecystokinin (CCK)	Appetite-inhibiting hormone CCK to be measured via commercially available ELISA kits (pg/ml).	To be measured pre-exercise, 0 minutes post-exercise, 30 minutes post-exercise, 60 minutes post-exercise, and 120 minutes post-exercise.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Appetite perceptions	Subjective appetite perceptions will be assessed using visual analogue scales (VAS) validated for four perceptions: hunger (i.e., "How hungry do you feel?"), satisfaction (i.e., "How satisfied do you feel?"), fullness (i.e., "How full do you feel?"), and prospective food consumption (i.e., "How much do you think you can eat?").	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Food Preferences	For food preferences, a state food preference questionnaire is a survey or questionnaire used to gather information about individuals' food preferences, and dietary habits.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Ad libitum meal energy intake	A post in-lab session meal will be provided to all participants to determine their ad libitum energy intake for this meal by measuring the food provided before the meal as well as the amount of food not consumed using an analog scale .	At the end of each in-lab session (exercise and seated rest; 2 meals total).
Free-living energy intake	Participants will complete a 3 day food record around each in lab session using a mobile application (Keenoa®) monitored by a registered dietician.	Day before, day of, and day after each in-lab session (6 days total).
Energy expenditure	Energy expenditure will be measured for the same 3 days of the food records around both in-lab sessions measured using a thigh-worn accelerometer.	Day before, day of, and day after each in-lab session (6 days total).
Estradiol	Sex hormone estradiol measured via radioimmunoassay (pg/mL).	Pre-exercise only.
Progesterone	Sex hormone progesterone measured via radioimmunoassay (ng/mL).	Pre-exercise only.
Testosterone	Sex hormone testosterone measured via radioimmunoassay.	Pre-exercise only.
Blood glucose	Will be measured using biochemical assays prior to and following treatment.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Insulin	Will be measured using biochemical assays prior to and following treatment.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
C-Peptide	Will be measured using biochemical assays prior to and following treatment.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Peripheral Blood Mononuclear Cells	Measured by flow cytometry and biochemical assays/arrays both before and after treatment and before and after an acute bout of exercise.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Inflammatory Cytokines	Measured by flow cytometry and biochemical assays/arrays both before and after treatment and before and after an acute bout of exercise.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Brain-derived Neurotrophic Factor (BDNF)	Measured in blood samples via ELISA kits.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Cathepsin B	Measured in blood samples via ELISA kits.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Irisin	Measured in blood samples via ELISA kits.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Klotho	Measured in blood samples via ELISA kits.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Adrenocorticotropic Hormone	Measured in blood samples via immunoassays.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Dickkopf-1 (DKK-1)	Measured in blood samples via immunoassays.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Fibroblast Growth Factor 23 (FGF-23)	Measured in blood samples via immunoassays.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Interleukin 1B (IL-1B)	Measured in blood samples via immunoassays.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Interleukin-6 (IL-6)	Measured in blood samples via immunoassays.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Tumor Necrosis Factor (TNF)	Measured in blood samples via immunoassays.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Osteocalcin	Measured in blood samples via immunoassays.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Osteopontin	Measured in blood samples via immunoassays.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Osteoprotegerin (OPG)	Measured in blood samples via immunoassays.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Parathyroid Hormone (PTH)	Measured in blood samples via immunoassays.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Sclerostin	Measured in blood samples via immunoassays.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.
Leptin	Measured in blood samples via immunoassays.	Pre-exercise/seated rest as well as 0 minutes, 30 minutes, 60 minutes and 120 minutes following exercise/seated rest.

Collaborators and Investigators

• Sponsor: Wilfrid Laurier University
• Investigators: Principal Investigator: Tom J Hazell, PhD, Wilfrid Laurier University

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): August 31, 2028
• Study Completion (Estimated): August 31, 2028

Study Registration Dates

• First Submitted: January 28, 2026
• First Submitted That Met QC Criteria: May 26, 2026
• First Posted (Actual): June 2, 2026

Study Record Updates

• Last Update Posted (Actual): June 2, 2026
• Last Update Submitted That Met QC Criteria: May 26, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: energy intake; appetite regulation; energy balance; ovarian hormones; appetite-regulating hormones; regulation of food intake
• Additional Relevant MeSH Terms: Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Polycyclic Compounds; Steroids; Fused-Ring Compounds; Estrenes; Estranes; Estradiol Congeners; Gonadal Steroid Hormones; Gonadal Hormones; Estradiol
• Other Study ID Numbers: EMRL-25-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Deidentified participant data from this research study will be available to researchers upon review and approval of reasonable requests starting six months after manuscript publication. Proposals should be sent to the corresponding author.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No