Challenging the Myth of Women Being Colder Than Men: A Thermophysiology Perspective

• Published in: Obesity (Silver Spring, Md.) Md.), 2022-11, Vol.30, p.289-289
• Main Authors: Thomas, Reed, Brychta, Robert, Lentz, Taylor, LaMunion, Samuel, Israni, Nikita, Fletcher, Laura, Courville, Amber, McGehee, Suzanne, Cypess, Aaron, Chen, Kong
• Format: Article
• Language: English
• Subjects: Body composition; Body fat; Gender differences; Heat; Temperature; Women
• ISSN: 1930-7381; 1930-739X

Background: There is a popular belief that women "feel colder" than men. Proposed reasons for the greater cold sensitivity are that women generate less heat with lower resting metabolic rates (RMR), have greater heat need due to warmer core temperatures (Tcore), and/or have cooler skin temperatures (Tskin) than men. However, few thermophysiology studies have directly compared women to men. To address this gap, we compared the RMR, Tcore and Tskin responses of lean healthy young men and women to different ambient temperatures experienced in daily living (18-31°C) in a well-controlled inpatient study. Methods: 16 women and 12 men completed a 7-10-day (in follicular phase) and 13-day inpatient stay, respectively. Each day from 0800-1300 we measured RMR by whole-room indirect calorimetry, Tcore by tympanic monitor, and multi-site Tskin by iButton sensors, in a constant ambient temperature under resting, fasted conditions with standard clothing. Ambient temperature order was randomized, and body composition was measured by dual x-ray absorptiometry. Results: The groups were comparable in age and BMI, but women had greater %body fat and less body surface area (BSA). RMR was similar between groups after normalizing to BSA. In ambient temperatures >26°C women and men had similar Tcore (37.0±0.3°C). At colder ambient temperatures (21.1±0.6°C) Tcore decreased less in women (36.8±0.2°C Vs 36.5±0.4°C, p