Which statement about heat stress is true?

Heat stress encompasses a range of heat-related illnesses, and understanding the symptoms associated with each condition is crucial. The statement that lack of sweat is a symptom of heatstroke is accurate. Heatstroke is a severe condition that can develop from prolonged exposure to high temperatures or intense physical activity in heat, and as the body's temperature regulation fails, a person may stop sweating. This cessation of sweating is a critical indicator, as it suggests that the body is unable to dissipate heat effectively, leading to dangerously high body temperatures.

In contrast, excessive sweating is typically associated with heat exhaustion, where the body remains able to sweat but is losing fluids and electrolytes at an alarming rate. Heat cramps can indeed signal the onset of heat-related issues, but they are not necessarily the first indicator of an illness. Additionally, heat stress can occur at various temperatures, particularly if the humidity is high or during physical exertion, not exclusively in high heat conditions. A nuanced understanding of these symptoms underscores the importance of recognizing and responding to heat stress appropriately.