Menthol Stimulation of Brown Adipose Tissue in Humans: Aim 1

Launched by INDIANA UNIVERSITY · Jun 12, 2025

Keywords

ClinConnect Summary

This clinical trial is studying whether applying menthol cream to the skin can activate a special type of body fat called brown adipose tissue (BAT), which helps the body burn energy and generate heat, especially in cold conditions. Researchers want to find out if using menthol on the skin can stimulate this fat to increase energy use, which might help with managing body weight and metabolism.

People who might be eligible to join are adults between 18 and 74 years old who speak English, have been doing at least 150 minutes of moderate exercise each week over the past year, and have a body fat percentage of 30% or less. Participants need to be cleared for physical activity and should not have certain health conditions like heart, lung, liver, kidney, or skin problems, nor be pregnant or using tobacco products. During the study, participants will have menthol cream applied to a small area of their skin to see if it activates their brown fat. The research team will carefully check for any skin reactions and follow up to ensure safety. This study is currently recruiting volunteers interested in helping us understand how menthol might influence energy use in the body.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • Fluency in English
• • Participate in 150 minutes or more of at least moderate intensity exercise per week during the previous year. Assessment of moderate intensity physical activity will be determined via the International Physical Activity Questionnaire (i.e., IPAQ) (described in detail in Section 7.0). This questionnaire defines moderate intensity exercise as "activities that take moderate physical effort and make you breathe somewhat harder than normal".
• • Body fat ≤ 30% as determined by DEXA scan
• • Be cleared for physical activity according to the 2020 Physical Activity Readiness Questionnnaire (PAR-Q+).
• Exclusion Criteria:
• • Any autonomic cardiovascular, metabolic, neurologic, endocrine, or respiratory disease, that, in the opinion of the investigator, would exclude them from participation.
• • Previously diagnosed liver and/or kidney dysfunction, including, but not limited to, acute and/or chronic kidney disease, cirrhosis, hepatitis, and fatty liver disease.
• • Women who are pregnant or breastfeeding.
• • Current use of tobacco or electronic cigarette, or regular (i.e., more than twice a week) use within the last 1 year.
• • History of peripheral cold injury, skin disorder (eczema, psoriasis), or excessive tattooing.
• • Known chronic (i.e., cancer, surgery) or acute conditions (i.e., diarrhea, constipation) of the rectum.
• • Menthol allergy (described in detail in Section 7.0 and 9.0). Menthol can cause skin irritation when applied topically, especially for people with sensitive skin or allergies. For this reason, recruited participants will be screened for a menthol allergy during the informed consent/screening visit. We will apply a small quantity of the cream (\~2ml) to an isolated body area to limit skin exposure. In the case a rash develops during the application of the cream, research staff will irrigate the area to remove the substance and limit further exposure. A 24-hour follow-up phone call initiated by research staff will be implemented to follow-up on all adverse reactions. Detectable BAT activation during a localized cold stress test (i.e., face cooling test) (procedure described in detail in Section 7.0).
• * Using medications with direct effects on the cardiovascular system including, but not limited to:
• • Anticoagulants.
• • Antiplatelet agents.
• • ACE Inhibitors.
• • Angiotensin II receptor blockers.
• • Angiotensin-receptor neprilysin inhibitors.
• • Beta blockers.
• • Calcium, potassium, or sodium channel blockers.
• • Cholesterol lowering medications.
• • Digitalis preparations.
• • Diuretics.
• • Vasodilators.
• • Anticholinergics.