Understanding the Differences Between Hot Sweat and Cold Sweat

Sweating is a natural physiological response the body uses to regulate temperature and respond to emotional states. Two common types of sweat—hot and cold—serve different purposes and are associated with distinct conditions.

Hot sweat, also known as thermoregulatory sweat, occurs mainly when the body needs to cool down from an increase in core temperature due to physical activity or external heat. When you exercise or are in a hot environment, your brain's hypothalamus detects the rise in temperature and signals the sweat glands—primarily eccrine glands in the skin—to produce sweat. This sweat, composed mostly of water and salt, evaporates from your skin, aiding in heat dissipation. Humans have a dense network of these eccrine glands, especially on the palms and soles.

In contrast, cold sweat, often termed psychological sweat, is triggered by emotional or mental stress, anxiety, fear, or pain. During such states, the brain's amygdala activates the hypothalamus, which then stimulates two pathways. First, it signals eccrine glands to produce sweat, usually cold and clammy. Second, it prompts the adrenal glands to release hormones like norepinephrine and epinephrine, stimulating apocrine glands located in areas such as the armpits and groin. Sweat from these glands tends to contain fats, proteins, and other substances, resulting in a different type of sweating.

Although sweat itself always has a similar temperature—close to body temperature—the context in which it is produced provides clues about its nature. Hot sweat typically occurs during physical exertion or heat exposure and helps regulate body temperature. Cold sweat, on the other hand, is more associated with emotional distress and can occur even when the body isn't overheated.

Regarding odor, sweat alone usually does not smell. However, bacteria on the skin can metabolize sweat, producing volatile organic compounds that generate body odor. Interestingly, stress-induced cold sweat may carry a distinctive smell, which can serve as an alert to others about a person's emotional state.

In summary, understanding whether sweat is hot or cold can provide insights into underlying health or emotional conditions. If you notice unusual sweating patterns or changes that concern you, consulting a healthcare professional is advised.

Source: https://medicalxpress.com/news/2025-10-difference-hot-cold.html