It’s the middle of winter, and you are standing on the bus stop, and you suddenly feel a cold breeze blow against you – your whole body shivers. You tend to cover your fingers and press your arms against your body to keep your body warm. However, amid this cold weather, you might notice that your face rarely seems to get cold at all. Sure, it is a must to cover your ears, nose, and mouth since they can let cold air into the body and cause difficulty in breathing. But besides that, even if you happen to be on the summit of a snowy mountain, it is generally safe for you to enjoy the view without having to cover every part of your face.
How come the face is so unique in this regard? Why is it that our cheeks or our forehead never feels too cold? Well, the answer lies in more than one factor. Also, it has to do with the perception of heat and cold and how our brain can adapt to ignore moderate hot and cold temperatures, which helps us survive in the long run.
It is essential to understand why it is that we feel hot or cold in the first place. The human body has mostly a constant temperature. Whether we feel hot or cold is determined by the skin temperature of our bodies, which is the temperature of the outermost layers. Typically, the temperature of the skin varies somewhere from 92.3 degrees Fahrenheit to 98.6 degrees. Protruded surfaces, like the nose, have lower temperatures and places like the chest and thighs, that have greater activity and blood flow, have a higher temperature.
In an environment where the temperature feels neither cold nor hot, the temperature of the air is almost the same as that of your skin temperature. Let’s call this the equilibrium temperature.Whenever the temperature varies from the equilibrium temperature, your skin feels either hot or cold.
Just as a heated object becomes cool in cold water and vice versa, your body also tries to be at the same temperature as that of your surroundings. If the surrounding temperature becomes colder than your skin temperature, your body gives off its heat to try and match the external temperature. This release of heat from the body produces the sensation of “cold.” The lower the temperature is, the more heat your body releases, and the colder your feel.
One factor that helps keep our face warm even when things are getting cold is the presence of the brain in the skull. The bran is, in a way, the most critical organ in the human body. It is also the organ that uses up most of our body’s energy. In fact, an estimated 20% of all of our body’s energy is used up by the brain. It primarily uses the energy to power the countless electrical impulses that are employed by neurons in order to communicate with each other. The “energy” required by the brain is, in reality, a bunch of chemicals, including oxygen and sugars, such as glucose. All of these essentials are packed together in the blood. So, what the brain needs is a constant and rapid flow of blood supply.
This flow of blood supply mostly takes place through the carotid artery that consists of blood vessels supplying blood to the neck, brain, and face. All the blood circulating through the face to reach the brain produces a lot of heat and friction. This makes sure that our face gets plenty of heat and stays warm. Similarly, the body’s two main breathing organs, the nose and the mouth are located on the face. When we breathe, we continually give off hot and warm clouds of carbon dioxide. This is also a contributory factor that produces abnormal heat in the face.
Hence, even when the temperature drops and the face loses heat, it remains unaffected as there is an ongoing supply of heat that keeps it warm. One other possible factor that helps us fight cold temperatures is the fact that there are probably very few cold receptors on our face and head, as they aren’t really needed. In contrast, our hands and the soles of our feet are very sensitive to temperature changes as they are much more likely to need to distinguish between different temperatures.