Acute Effects of Ultra-processed Versus Unprocessed Foods on Glucocorticoid Secretion in Healthy Individuals (UltraCort)

The investigators aim to understand whether the acute cortisol response to food differs between differently processed foods.

In this monocentric, randomized, cross-over, open-label study, 20 healthy volunteers will receive two differently processed meals of similar caloric content and composition. The study will primarily focus on changes in blood cortisol levels, but other metabolic parameters will also be compared.

Study Overview

• Status: Completed
• Conditions: Glucocorticoids; Food Effect; Obesity and Overweight
• Intervention / Treatment: Other: Ultra-processed breakfast; Other: Low-processed breakfast

Detailed Description

Obesity is one of the most serious health problems of the 21st century, with ultra-processed diets being a major driver of the current obesity pandemic. Understanding how these diets affect body weight is critical to identifying new treatment targets. Current evidence suggests that the degree of food processing may affect cortisol secretion, a hormone that plays a key role in body weight regulation by increasing with acute food intake and promoting energy storage in adipose tissue. However, whether ultra-processed foods enhance cortisol response has not been thoroughly investigated.

Here, the investigators aim to understand the reaction of GCs in response to different processed foods in healthy volunteers. No medication will be used in this study.

Participants will be asked to refrain from strenuous physical activity and alcohol consumption for 24 hours prior to the study. They will fast for 12 hours before consuming a high-calorie, low-processed meal. After fasting again, participants will consume a high-calorie, ultra-processed meal on a second study day. The order of the meals is not fixed. The study will include a screening visit and two study visits.

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Canton of Basel-City
    • Basel, Canton of Basel-City, Switzerland, 4031
      • University Hospital Basel

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Males aged 18 to 40 years
• BMI 18.5-29.9 kg/m2

Exclusion Criteria:

• Severe acute or chronic disease
• Lactose intolerance
• Severe food allergy
• Casual smoking (more than six cigarettes per day)
• Frequent, heavy alcohol consumption (more than 30g/day)
• Frequent, heavy caffeine consumption (more than 4 caffeinated drinks/day)
• Regular physical exercise (more than 4hrs per week)
• Shift work
• Previous enrollment in a clinical trial within the past two months
• Intake of any steroid-containing drugs, including topical steroids and inhalers, within four weeks of the study initiation
• Contradictions to undergo the investigated intervention
• Inability or unwillingness to provide informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Ultra-processed breakfast; During one study phase, subjects receive an ultra-processed breakfast	Other: Ultra-processed breakfast; With this intervention, participants will consume ultra-processed foods
Active Comparator: Low-processed breakfast; During the other study phase, subjects receive a low-processed breakfast	Other: Low-processed breakfast; With this intervention, participants will consume low-processed foods

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood cortisol change	Change in blood cortisol assessed by repeadidly collecting blood before and after the meal	Up to six weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Energy expenditure (basal metabolic rate, diet-induced thermogenesis	Basal metabolic rate measured with indirect calorimetry	Up to six weeks
Substrate utilization (respiratory quotient)	Respiratory quotient assessed with indirect calorimetry	Up to six weeks
Body composition	Body impedance analysis before meal	Up to six weeks
Satiety	Appetite rating with visual analogue scale (VAS) from 0mm-100mm (0mm=not at all and 100mm=extreme)	Up to six weeks
Weight	Measurement of weight with a standard scale	Up to six weeks
Motivation to eat	Motivation to eat measured with a speed clicking test	Up to six weeks
Systolic and diastolic blood pressure	Assessment of blood pressure with a standard blood pressure monitor	Up to six weeks
Lipids (total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglycerides)	Blood collection fasted	Up to six weeks
Perceived stress	Measured by perceived stress questionnaire	Up to six weeks
C-peptide	Change in blood cortisol assessed by repeadidly collecting blood before and after the meal	Up to six weeks
Insulin	Change in blood cortisol assessed by repeadidly collecting blood before and after the meal	Up to six weeks
Blood glucose	Change in blood glucose assessed by repeadidly collecting blood before and after the meal	Up to six weeks
Neuroendocrine hormones (thyroid hormones, GLP1, glucagon, ACTH)	Change in blood cortisol assessed by repeadidly collecting blood before and/or after the meal	Up to six weeks

Collaborators and Investigators

• Sponsor: Eleonora Seelig
• Investigators: Principal Investigator: Eleonora Seelig, PD Dr. med., Sponsor and principal investigator

Study record dates

Study Major Dates

• Study Start (Actual): October 30, 2024
• Primary Completion (Actual): July 4, 2025
• Study Completion (Actual): July 4, 2025

Study Registration Dates

• First Submitted: September 27, 2024
• First Submitted That Met QC Criteria: December 4, 2024
• First Posted (Actual): December 9, 2024

Study Record Updates

• Last Update Posted (Actual): March 3, 2026
• Last Update Submitted That Met QC Criteria: March 2, 2026
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Overweight; Obesity
• Other Study ID Numbers: EKNZ 2024-01796

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

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