Reader PartiallyDeflected wrote in to ask, “Since our body temperature is around 98 degrees, why do we feel hot when it’s 90?”
Pretty much everything your body does, whether physical (like muscle contractions) or chemical (like some stages of digestion), produces heat as a byproduct. You’re constantly generating it, and constantly losing it to the environment. The hypothalamus, an almond-sized chunk of the brain that rests deep within its squishy confines, acts as the body’s thermostat and tries to keep the amount of heat created and the amount lost close to each other and maintain normal body temperature.
Normally, this is easy enough. Heat seeks equilibrium, a state where everything is the same temperature as everything around it. It’s why a bowl of hot soup and a glass of ice water will both reach room temperature if you leave them out on the counter long enough. Usually, the environment around you is cooler than your body, so your little thermostat can just dump the excess heat into it with thermoregulatory processes like sweating (where the heat is lost by evaporation) and increasing bloodflow through capillaries close to the surface of the skin (where the heat is lost through radiation, convection and conduction).
For the rest of the story: http://mentalfloss.com/article/50080/why-do-we-feel-hot-temperatures-lower-our-body-temp