Short cold sessions to grow and activate brown fat
Official title: Investigating the Cellular Heterogeneity of Human Brown Adipose Tissue and Its (Patho)Physiological Regulation
Run by University of Edinburgh · NCT07048405 · Data updated 2026-11-12
This study will test whether daily two-hour cold sessions in healthy adults (ages 18–40) change the activity and gene patterns of brown fat, white fat, and muscle.
Quick facts
| Study type | Interventional |
|---|---|
| Ages | 18 Years to 40 Years |
| Sex | All |
| Enrollment | 12 (estimated) |
| Sponsor | University of Edinburgh Academic / other |
| Locations | 1 site (Edinburgh) |
| Status | Recruiting |
| Started | May 1, 2025 |
| Main results expected | July 2027 |
| Study ends | July 2027 |
| Registry record updated | June 30, 2026 |
| Trial ID | NCT07048405 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Ideal participants are healthy adults aged 18–40 with BMI 18.5–25 kg/m2, stable weight, no regular medications, no major medical conditions, and able to undergo PET/CT scans and tissue biopsies.
✕Probably not a fit
People with chronic illnesses, outside the age or BMI ranges, who are pregnant or breastfeeding, on regular medications, claustrophobic, or unable to tolerate biopsies or PET/CT scans are unlikely to benefit from participation.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
Healthy adults will undergo baseline warm and cold measurements including energy expenditure, skin and core temperature, and a dynamic whole-body 18F-FDG PET/CT scan. Tissue biopsies (supraclavicular brown adipose tissue, vastus lateralis muscle, and periumbilical subcutaneous white adipose tissue) will be taken before and after a 10-day cold-acclimation protocol consisting of 2 hours per day using water-perfused cooling blankets. The trial will compare PET/CT imaging, physiological measures, and molecular analyses to identify cellular heterogeneity and gene-expression changes in thermogenic tissues. Results will map how repeated short cold exposure remodels tissue composition and transcriptional programs.
Why it matters
Potential benefit: If successful, findings could identify ways to boost brown fat activity and mass that may improve metabolism and lower cardiometabolic risk.
How similar studies have gone: Prior studies have shown intermittent cold increases brown fat activity and mass on 18F-FDG PET/CT, but the detailed cellular and molecular adaptations are largely untested.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: * Aged 18-40 years * Body mass index 18.5-25 kg/m2 * Weight change of less than 5% in the past 6 months * No acute or chronic medical conditions * On no regular medications (other than contraceptives in female participants) * No claustrophobia * Alcohol intake ≤14 units/ week * Screening blood tests within acceptable limits (of no clinical significance) * Not currently pregnant, lactating or breastfeeding (female participants only) * Ability to provide informed consent. Exclusion Criteria: * Not meeting inclusion criteria * Contra-indication to PET/CT scan * Allergy to local anaesthetic
Where it's running
-
Royal Infirmary of Edinburgh
Edinburgh, United Kingdom Recruiting
Study contacts
- Study coordinator: María Paula Huertas Caycedo
- Email: m.p.huertas-caycedo@sms.ed.ac.uk
- Phone: 01312429196
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How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.