Women face greater physiological vulnerability to extreme heat than men, driven by biological differences that alter how their bodies regulate temperature. Female reproductive hormones, particularly estrogen, suppress the sweating response and reduce blood vessel dilation, two critical mechanisms for cooling. This hormonal fluctuation intensifies during menstrual cycles and menopause, when core body temperature rises and heat tolerance drops significantly.
Body composition plays a role too. Women typically carry higher percentages of body fat, which insulates heat rather than dissipating it. Men's greater muscle mass generates more metabolic heat but also facilitates faster cooling through increased blood flow to the skin.
Heat sensitivity compounds during pregnancy, when metabolic rates spike and the body struggles to shed excess warmth. Pregnant women face elevated risks of heat-related illness and adverse fetal outcomes during high-temperature periods.
Behavioral and occupational factors amplify these biological disadvantages. Women comprise the majority of outdoor workers in agriculture and construction across many regions, exposing them to prolonged heat without adequate cooling infrastructure. Clothing choices, often dictated by social expectations rather than thermal comfort, further restrict heat dissipation.
The gender gap widens in aging populations. Postmenopausal women experience persistent temperature regulation problems, losing estrogen's protective effects but gaining increased vulnerability to dehydration and heat stroke. Older men retain better thermoregulatory capacity.
Public health systems have historically overlooked these differences, designing heat-warning systems and emergency protocols around male physiology. Climate change intensifies the stakes. As heat waves grow more frequent and severe, women face compounding health risks without targeted prevention strategies. Healthcare providers now recognize the need for gender-specific heat illness protocols and workplace standards that account for female physiology, particularly in vulnerable populations like pregnant women and older adults.