Caffeine-Induced ThermogenesisNCT07868302
Caffeine-Induced Thermogenesis Assessed by Infrared Thermography
A study testing Carbohydrate Gel and Caffeine in people with Caffeine-Induced Thermogenesis and Brown Adipose Tissue Activation, run by Istanbul Health and Technology University at 1 site in Turkey (Türkiye).
Trial summary
This study evaluated thermogenic and physiological responses to 200 mg of caffeine administered following a carbohydrate gel in healthy adults. A total of 36 participants were included and grouped according to body mass index as normal weight, overweight, or obesity. The experimental protocol lasted 120 minutes. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Caffeine-Induced Thermogenesis, Brown Adipose Tissue Activation
- What is being tested?
- Carbohydrate Gel and Caffeine
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 36 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 10 Dec 2024to 12 May 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Healthy adults aged 18 years or older.
- Male or female participants.
- For female participants, regular menstrual cycles and participation during the follicular phase (days 4-8 of the menstrual cycle).
- Provision of written informed consent.
Who cannot join
- Diabetes or other metabolic diseases.
- Use of prescribed medication.
- Specific treatment for obesity, including bariatric surgery or anti-obesity medication.
- Caffeine intolerance or caffeine allergy.
- Regular exercise or physical activity for ≥6 months.
- Use of supplements that may increase brown adipose tissue activity for ≥3 months (e.g., fish oil, caffeine, or EGCG).
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- Irregular menstrual cycles.
- Pregnancy or lactation.
- Habitual alcohol consumption.
Trial locations and contacts
1 site in 1 country.
Turkey (Türkiye)1 site
Istanbul Health and Technology University
Istanbul, Istanbul, 34445
About this study
Official title: Determination of the Effect of Caffeine, a Thermogenic Dietary Component, on Brown Adipose Tissue Activation Using Infrared Thermography
This study evaluated thermogenic and physiological responses to 200 mg of caffeine administered following a carbohydrate gel in healthy adults. A total of 36 participants were included and grouped according to body mass index as normal weight, overweight, or obesity. The experimental protocol lasted 120 minutes. Participants received a carbohydrate gel at the beginning of the study, followed by 200 mg of caffeine 45 minutes later. Infrared thermography was used to assess temperature changes in the supraclavicular region, an area associated with brown adipose tissue activity. Core temperature, blood pressure, and heart rate were also measured at several time points. The study aimed to determine whether thermogenic and physiological responses differed according to body mass index and sex. It also evaluated whether absolute temperature values obtained directly from infrared thermography were sufficient on their own to characterize brown adipose tissue-related thermal responses. In addition, the study examined whether other thermal parameters provided complementary information for the interpretation of these responses.
- Being tested
- Carbohydrate Gel, Caffeine
- Keywords
- caffeine, Infrared Thermography, Brown Adipose Tissue, Thermogenesis, Body Mass Index, Sex
- Medical subject headings
- Coitus
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Carbohydrate GelDietary supplement
Participants received a carbohydrate gel providing 53 g of carbohydrate (PowerGel Mojito, Ingobio, Türkiye) at the beginning of the 120-minute experimental protocol.
CaffeineDietary supplement
Participants received one capsule containing 200 mg of caffeine (Nature's Supreme Caffeine, Türkiye) at 45 minutes during the 120-minute experimental protocol.
| Study group | Role | What they receive |
|---|---|---|
| Carbohydrate Gel Followed by Caffeine | Experimental | All participants received a carbohydrate gel at the beginning of the 120-minute experimental protocol, followed by 200 mg of caffeine at 45 minutes Receives: Dietary Supplement: Carbohydrate Gel; Dietary Supplement: Caffeine |
What is being measured
The primary outcome is the main question the study is designed to answer.
Supraclavicular Temperature (Tscv)
Right and left supraclavicular regions of interest (ROIs) were manually delineated as triangular areas on infrared thermographic images. For each ROI, the infrared thermography software calculated the mean temperature of the entire delineated area, yielding separate right and left Tscv values. Mean Tscv was then calculated as the arithmetic mean of the right and left Tscv values. Temperature was expressed in degrees Celsius (°C).
Measured: Infrared thermography measurements were repeated every 15 minutes throughout the 120-minute experimental protocol, at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min.
Reference Region Temperature (Tref)
A circular region of interest (ROI) was manually delineated over the BAT-free sternal region on infrared thermographic images. The infrared thermography software calculated the mean temperature of the entire delineated ROI, yielding the reference region temperature (Tref). Temperature was expressed in degrees Celsius (°C).
Measured: IRT measurements were repeated every 15 minutes throughout the 120-minute experimental protocol, at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min.
Relative Supraclavicular Temperature (Trel)
Relative supraclavicular temperature (Trel) was calculated as the difference between supraclavicular temperature (Tscv) and reference region temperature (Tref) at each measurement time point (Trel = Tscv - Tref). Right and left Trel values were calculated separately using the corresponding right and left Tscv values and the Tref value. Mean Trel was then calculated as the arithmetic mean of the right and left Trel values. Trel was expressed in degrees Celsius (°C).
Measured: Trel was calculated using the Tscv and Tref values measured by infrared thermography at each time point of the 120-minute experimental protocol: baseline (0 min) and 15, 30, 45, 60, 75, 90, 105, and 120 min.
Delta Temperature (ΔT)
Delta temperature (ΔT) was calculated as the change in supraclavicular temperature from the resting/baseline temperature (Td). The supraclavicular temperature measured at baseline (0 min), before carbohydrate gel administration, was defined as Td. Carbohydrate gel was administered after the baseline measurement, and caffeine was administered at 45 min. Supraclavicular temperatures measured at each subsequent time point (15, 30, 45, 60, 75, 90, 105, and 120 min) were considered stimulated temperatures (Ts), and ΔT was calculated as Ts - Td. Thus, ΔT at each time point represented the change in supraclavicular temperature relative to the baseline value. Right and left ΔT values were calculated separately, and mean ΔT was calculated as the arithmetic mean of the right and left ΔT values. ΔT was expressed in degrees Celsius (°C).
Measured: ΔT was calculated using supraclavicular temperature (Tscv) values measured by infrared thermography (IRT), with the baseline (0 min) Tscv value used as the resting temperature (Td), at 15, 30, 45, 60, 75, 90, 105, and 120 min during the 120-minute experi
Secondary outcomes (4)
Estimated Core Temperature
Estimated core temperature was assessed from the forehead using a non-contact infrared thermometer and was expressed in degrees Celsius (°C).
Measured: Estimated core temperature was measured at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min during the 120-minute experimental protocol.
Systolic Blood Pressure
Systolic blood pressure was measured using an automated sphygmomanometer and was expressed in millimeters of mercury (mmHg).
Measured: Systolic blood pressure was measured at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min during the 120-minute experimental protocol.
Diastolic Blood Pressure
Diastolic blood pressure was measured using an automated sphygmomanometer and was expressed in millimeters of mercury (mmHg).
Measured: Diastolic blood pressure was measured at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min during the 120-minute experimental protocol.
Heart Rate
Heart rate was measured using an automated sphygmomanometer and was expressed in beats per minute (bpm).
Measured: Heart rate was measured at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min during the 120-minute experimental protocol.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Oct 2026
- Study start10 Dec 2024
- Primary completion12 May 2025
- Study completion12 May 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Caffeine-Induced ThermogenesisStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- All participants received a carbohydrate gel at the beginning of the protocol, followed by 200 mg of caffeine at 45 minutes during the same 120-minute experimental session.
- Masking
- None (open label)
- Enrolment
- 36 participants (actual)
Sponsor and investigators
- Lead sponsor
- Istanbul Health and Technology University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Zeynep Ercan Karakaya, Istanbul Health and Technology University
- Investigators
- Zeynep Ercan Karakaya, PhD, Principal investigator, Istanbul Health and Technology University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07868302
- Sponsor's protocol ID
- ISTUN-CAFF-IRT-2025
- Status last verified
- Oct 2026
- First submitted
- 3 Oct 2026
- Last updated
- 9 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data will not be shared because no data-sharing plan was specified in the original study protocol or informed consent documents.
Study at a glance
From the registry record, last updated by the sponsor on 9 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Determination of the Effect of Caffeine, a Thermogenic Dietary Component, on Brown Adipose Tissue Activation Using Infrared Thermography
- ClinicalTrials.gov ID
- NCT07868302
- Acronym / sponsor ID
- ISTUN-CAFF-IRT-2025
- Keywords
- caffeine, Infrared Thermography, Brown Adipose Tissue, Thermogenesis, Body Mass Index, Sex
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 36 participants (actual)
- Lead sponsor
- Istanbul Health and Technology UniversityUniversity, hospital or other
- Study start
- 10 Dec 2024 (actual)
- Primary completion
- 12 May 2025 (actual)
- Study completion
- 12 May 2025 (actual)
- First posted
- 9 Oct 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study evaluated thermogenic and physiological responses to 200 mg of caffeine administered following a carbohydrate gel in healthy adults. A total of 36 participants were included and grouped according to body mass index as normal weight, overweight, or obesity. The experimental protocol lasted 120 minutes. Participants received a carbohydrate gel at the beginning of the study, followed by 200 mg of caffeine 45 minutes later. Infrared thermography was used to assess temperature changes in the supraclavicular region, an area associated with brown adipose tissue activity. Core temperature, blood pressure, and heart rate were also measured at several time points. The study aimed to determine whether thermogenic and physiological responses differed according to body mass index and sex. It also evaluated whether absolute temperature values obtained directly from infrared thermography were sufficient on their own to characterize brown adipose tissue-related thermal responses. In addition, the study examined whether other thermal parameters provided complementary information for the interpretation of these responses.
Study design
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- All participants received a carbohydrate gel at the beginning of the protocol, followed by 200 mg of caffeine at 45 minutes during the same 120-minute experimental session.
| Arm | Type | Receives |
|---|---|---|
| Carbohydrate Gel Followed by Caffeine | Experimental | Dietary Supplement: Carbohydrate Gel, Dietary Supplement: CaffeineAll participants received a carbohydrate gel at the beginning of the 120-minute experimental protocol, followed by 200 mg of caffeine at 45 minutes |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Healthy adults aged 18 years or older.
- Male or female participants.
- For female participants, regular menstrual cycles and participation during the follicular phase (days 4-8 of the menstrual cycle).
- Provision of written informed consent.
Key exclusion criteria (9 listed)
- Diabetes or other metabolic diseases.
- Use of prescribed medication.
- Specific treatment for obesity, including bariatric surgery or anti-obesity medication.
- Caffeine intolerance or caffeine allergy.
- Regular exercise or physical activity for ≥6 months.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Carbohydrate GelParticipants received a carbohydrate gel providing 53 g of carbohydrate (PowerGel Mojito, Ingobio, Türkiye) at the beginning of the 120-minute experimental protocol. | Dietary supplement | Carbohydrate Gel Followed by Caffeine |
| CaffeineParticipants received one capsule containing 200 mg of caffeine (Nature's Supreme Caffeine, Türkiye) at 45 minutes during the 120-minute experimental protocol. | Dietary supplement | Carbohydrate Gel Followed by Caffeine |
Primary outcome
Supraclavicular Temperature (Tscv)
Time frame: Infrared thermography measurements were repeated every 15 minutes throughout the 120-minute experimental protocol, at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min.
Right and left supraclavicular regions of interest (ROIs) were manually delineated as triangular areas on infrared thermographic images. For each ROI, the infrared thermography software calculated the mean temperature of the entire delineated area, yielding separate right and left Tscv values. Mean Tscv was then calculated as the arithmetic mean of the right and left Tscv values. Temperature was expressed in degrees Celsius (°C).
Reference Region Temperature (Tref)
Time frame: IRT measurements were repeated every 15 minutes throughout the 120-minute experimental protocol, at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min.
A circular region of interest (ROI) was manually delineated over the BAT-free sternal region on infrared thermographic images. The infrared thermography software calculated the mean temperature of the entire delineated ROI, yielding the reference region temperature (Tref). Temperature was expressed in degrees Celsius (°C).
Relative Supraclavicular Temperature (Trel)
Time frame: Trel was calculated using the Tscv and Tref values measured by infrared thermography at each time point of the 120-minute experimental protocol: baseline (0 min) and 15, 30, 45, 60, 75, 90, 105, and 120 min.
Relative supraclavicular temperature (Trel) was calculated as the difference between supraclavicular temperature (Tscv) and reference region temperature (Tref) at each measurement time point (Trel = Tscv - Tref). Right and left Trel values were calculated separately using the corresponding right and left Tscv values and the Tref value. Mean Trel was then calculated as the arithmetic mean of the right and left Trel values. Trel was expressed in degrees Celsius (°C).
Delta Temperature (ΔT)
Time frame: ΔT was calculated using supraclavicular temperature (Tscv) values measured by infrared thermography (IRT), with the baseline (0 min) Tscv value used as the resting temperature (Td), at 15, 30, 45, 60, 75, 90, 105, and 120 min during the 120-minute experi
Delta temperature (ΔT) was calculated as the change in supraclavicular temperature from the resting/baseline temperature (Td). The supraclavicular temperature measured at baseline (0 min), before carbohydrate gel administration, was defined as Td. Carbohydrate gel was administered after the baseline measurement, and caffeine was administered at 45 min. Supraclavicular temperatures measured at each subsequent time point (15, 30, 45, 60, 75, 90, 105, and 120 min) were considered stimulated temperatures (Ts), and ΔT was calculated as Ts - Td. Thus, ΔT at each time point represented the change in supraclavicular temperature relative to the baseline value. Right and left ΔT values were calculated separately, and mean ΔT was calculated as the arithmetic mean of the right and left ΔT values. ΔT was expressed in degrees Celsius (°C).
4 secondary outcomes
Estimated Core Temperature
Time frame: Estimated core temperature was measured at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min during the 120-minute experimental protocol.
Systolic Blood Pressure
Time frame: Systolic blood pressure was measured at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min during the 120-minute experimental protocol.
Diastolic Blood Pressure
Time frame: Diastolic blood pressure was measured at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min during the 120-minute experimental protocol.
Heart Rate
Time frame: Heart rate was measured at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min during the 120-minute experimental protocol.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Oct 2026.
- Individual participant dataSharing planned: No. Individual participant data will not be shared because no data-sharing plan was specified in the original study protocol or informed consent documents.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Zeynep Ercan Karakaya, PhD principal investigator
Istanbul Health and Technology University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Carbohydrate Gel and Caffeine in people with Caffeine-Induced Thermogenesis and Brown Adipose Tissue Activation, run by Istanbul Health and Technology University at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 9 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Supraclavicular Temperature (Tscv) (time frame: Infrared thermography measurements were repeated every 15 minutes throughout the 120-minute experimental protocol, at baseline (0 min) and at 15, 30, 45, 60, 75, 90, 105, and 120 min.). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 9 Oct 2026.