NCT05822141 · Indiana University
Omega-3 Fatty Acids as Regulators of Brown Adipose Tissue During Cold Exposure
What this study is about
This clinical trial will assess the whether fish oil supplementation can modulate brown fat activation, shivering, thermal comfort and skin blood flow during cold exposure.
View original scientific description
This clinical trial will assess the whether fish oil supplementation can modulate brown fat activation, shivering, thermal comfort and skin blood flow during cold exposure.
Interventions
DIETARY_SUPPLEMENT
Fish Oil
For 12 weeks subjects will ingest 6 capsules per day of fish oil (7.8 g/day total omega--3 fatty acids: 3.75 g/day EPA and 1.5 g/day DHA)
DIETARY_SUPPLEMENT
Placebo
For 12 weeks subjects will ingest 6 capsules per day of olive oil (each capsule contains 990 mg of olive oil)
Primary outcome measures
Core Temperature:
Time frame: 125 minutes
Core body temperature will be continuously measured by a rectal probe
Metabolic Measurements (indirect calorimetry):
Time frame: 125 minutes
Metabolic rate will be measured via indirect calorimetry (i.e., via the analysis of expired gases and ventilation).
Indices of Shivering
Time frame: 125 minutes
Surface mechanomyography will be assessed by three triaxial accelerometers adhered to the skin using adhesive tape on the chest, upper back, and thigh will be used to assess shivering
Minnesota Manual Dexterity Test (MMDT)
Time frame: 10 minutes
The MMDT \[28,29,30\] consists of a 60-hole, thin board with red and black blocks (3.7cm) and is comprised of the turning test and the placing test. During the turning test will be modified to only use the dominant hand. During this task, the participant takes a block from the top right corner with their dominant and places it in the hole with their dominant hand. During the placing test, the participant takes one at a time in their dominant hand and places the black in the whole on the board. Scoring of this test is the time it takes to complete each test.
Thermal Perception Scales
Time frame: 125 minutes
Thermal perceptions will be assessed using Likert scales for thermal discomfort and thermal sensation. Thermal perceptions will be assessed using Likert scales for thermal discomfort and thermal sensation. Participants will complete Likert scales to assess their thermal comfort (1 = comfortable, 4 = very uncomfortable) and thermal sensation (1 = cold, 4 = neutral, 7 = hot).
Thermal Comfort (behavior)
Time frame: 125 minutes
A series of small tubes will be placed on the back of the participant's neck. The participants will control the temperature of the water perfusing these tubes by turning a valve. This will allow for the voluntary control of neck temperatures from 20-35 degrees Celsius. Participants will be instructed to control the temperature of the water bath so that their neck will always be thermally comfortable
Infrared Thermography
Time frame: 125 minutes
An infrared thermography camera will be used to measure skin temperature in the supraclavicular (i.e., collar bone) region. This provides a non-invasive estimate of brown adipose tissue activation
Cold Chamber Challenge
Time frame: 125 minutes
The environmental chamber set to 29 degrees Celsius (C; 84 degrees Fahrenheit, F) at the beginning of the experimental visit. While in the chamber, participants will be instructed to be sedentary. The chamber will then be cooled at a rate of 1 deg C per 5 minutes until 4 deg C (39.2 deg F) is reached (\~125 minutes) with a wind speed of 4.5 m/s. Once 4 deg C air temperature is reached, participants will remain in the chamber for an additional 30 minutes or until the participant can no longer tolerate the cold or if rectal temperature falls below 35.5 deg C (95.9 deg F).
24 Hour Dietary Recalls
Time frame: 12 weeks
Participants will be asked to record all food, beverages and supplements consumed during a 24-hour period pre-supplementation, and every 2 weeks during the supplementation period for a total of \~7 dietary recalls to ensure that dietary habits do not change during the 12 week supplementation period.
Skin Temperature
Time frame: 125 minutes
Wireless temperature sensors (iButtons, Maxim Inc.) will be attached to 12 sites on the body (forehead, calf, thigh, foot, quadriceps, hamstring, chest, abdomen, upper back, lower back, forearm, and hand) using adhesive tape to measure skin temperature.
Nine Hole Peg Test (NHPT)
Time frame: 10 minutes
The NHPT, a manual dexterity test, consists of 9 holes (10mm diameter, 15mm depth) separated by 32mm, and 9 pegs (7mm diameter, 32mm length). During the test, participants will be instructed to take the pegs from a container one by one and place them into the holes on the board as quickly as possible, with their dominant hand. Scoring of this test is the time it takes to complete each test.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Male and female, between the ages of 18 to 40 years.
- Body Mass Index (BMI) of 18.5 to 24.9 kg/m2
- Considered "moderately to highly active" by the International Physical Activity Questionnaire (IPAQ) and the Physical Activity Readiness Questionnaire (PAR-Q+)
Exclusion criteria
- History of smoking or recreational smoking, hyperlipidemia, hypertension/cardiovascular disease, diabetes, renal disease, neurological disease, metabolic disease, and bleeding disorders or delayed clotting time.
- Taking SSRI's (antidepressants and anxiety medication), ADD/ADHD medication, and chronically consume pain medication (Aleve, Tylenol, CBD, etc).
- Have or have had chronic disorders of the rectum (e.g., cancer, surgery, active hemorrhoids, etc.) or who currently have related acute conditions (diarrhea, constipation, etc.).
- Have or have had a diagnosis of disorders related to immune suppression and/or autoimmune disease.
- Are pregnant or planning on being pregnant.
- Resting blood pressure of \> 130mmHg systolic or 90 mmHg diastolic.
- Resting Pulse rate of \> 100 bpm.
- History of regularly consuming fish oil supplements and/or regularly eating more than one fish meal per week.
- Consuming more than one fish meal per week during the study.
Where
- Bloomington, Indiana
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 26, 2026 · Source of record for eligibility and locations