The sensation of “hot tears” is a commonly described experience, usually occurring during moments of intense emotional distress or pain. The perceived warmth of these tears rolling down the face suggests a direct link between emotional intensity and physical sensation. The reality is that the sensation of heat is not due to a dramatically increased temperature of the tear fluid itself. Instead, it results from a combination of internal physiological responses and external physical effects on the skin. Understanding this experience requires looking closely at the different types of tears the body produces, the body’s reaction to stress, and the physics of how liquid interacts with the skin.
The Three Types of Tears
The human eye produces three distinct categories of tears, each with a different function and composition. Basal tears are produced continuously to lubricate the eye, nourish the cornea, and protect the surface from dust and bacteria. Reflex tears are a rapid response to physical irritants, such as dust or smoke, working to flush foreign material away. Emotional tears are generated in response to strong feelings like joy, grief, or stress.
While all tears are primarily composed of water, electrolytes, and proteins, emotional tears contain higher levels of certain stress hormones, including adrenocorticotropic hormone and prolactin. Some researchers theorize that producing these tears may be a mechanism for the body to excrete these chemicals, contributing to the feeling of relief after crying.
The Physiological Reality Behind the Sensation
The tears themselves are produced at the body’s internal core temperature, consistently around 98.6°F (37°C). The perceived “hotness” is largely a result of physiological changes occurring during an intense emotional episode. When a person cries intensely, the sympathetic nervous system, responsible for the “fight or flight” response, is activated. This response causes a localized increase in blood flow to the face and head.
The surge of blood flow causes the small blood vessels in the face and around the eyes to dilate, making the skin in these areas warmer and more sensitive. When tears at normal body temperature contact this warmer skin, they feel significantly hotter than tears shed during a calmer state. Intense emotional stress can also cause a slight, temporary increase in overall core body temperature, contributing to the striking sensation that the tears are scalding.
How Evaporation Affects Temperature Perception
The physical process of evaporation also plays a role in how the temperature of the tears is perceived as they travel down the cheek. Evaporation is a cooling process, as it requires heat energy to change the liquid water into vapor, which is why sweat cools the skin. However, the sensation of wetness and the contrast with the skin can create a paradoxical perception of warmth. When a tear begins to evaporate on the skin, it pulls heat away from the skin’s surface, cooling that specific spot.
The tear liquid that remains on the skin, which is still at body temperature, can feel warmer in contrast to the slightly cooled skin it has just passed over. This is especially true when a large volume of tears is flowing rapidly during intense crying. The movement of the warm, salty fluid across the highly sensitive skin of the face, which is already flushed from increased blood flow, registers as a strong sensory signal that the brain interprets as heat.
The Hormonal Link to Intense Crying
The systemic emotional context that drives the physiological heat increase is intrinsically linked to the body’s hormonal response to distress. Intense emotional states trigger a cascade of hormonal releases from the endocrine system. The adrenal glands release stress hormones like cortisol and adrenaline, which are the primary drivers of the sympathetic nervous system activation.
This hormonal surge initiates physical changes, including the increased heart rate and the redistribution of blood flow throughout the body. Adrenaline and cortisol prepare the body for a perceived threat, and the resulting vasodilation—the widening of blood vessels—in the face is a direct consequence of this systemic activation. The physical warmth experienced during a highly emotional moment is a side effect of the body mobilizing its resources under the direction of these stress hormones.