My mother used to tell us to put a hat on to go outside to play in the winter because we lose most of our heat through our heads.
It turns out that’s not entirely true.
While a hat can definitely prevent the heat loss that occurs through the head, and therefore keep you warmer, we don’t actually lose MOST of our body heat through our head.
Yes, there are people who actually study these things.
Jolie Bookspan is one such person. Through her work designing rigorous experiments for military survival training, she has found out that we really lose less than 20-30% of our body heat through the head. (Interestingly, the colder it is, the higher the percentage of heat lost through the head, she tells us. At zero degrees Centigrade, we could lose as much as 35% of our body heat through our heads! That percentage also depends on what you’re doing: if you’re exercising outside, it then becomes a smaller percentage.)
Where did the head-heat-loss myth come from?
The Guardian reports a new study that debunks the popular myth. The site tells us, “The myth is thought to have arisen through a flawed interpretation of a vaguely scientific experiment by the US military in the 1950s. In those studies, volunteers were dressed in Arctic survival suits and exposed to bitterly cold conditions. Because it was the only part of their bodies left uncovered, most of their heat was lost through their heads.”
However, in response to the new study mentioned in the Guardian, Kenneth J Collins, a clinical physiologist, brings up a concern. What if people, particularly the elderly, forego hats if they learn that this myth is actually false? The study, he says, ignores the fact that cooling on the head and face actually can have important bodily effects. It seems that cool air on the face can cause systemic cardiovascular reflex responses, and that body temperature can be selectively influenced by cooling of the head and face.
Remember, babies’ heads are bigger, relatively
So, while it may be true we don’t lose MOST of our body heat through the head, 20-30% is still a big number. Imagine what this means for babies, who have even bigger heads relative to their body size, and therefore more surface area from which heat can escape.
So, don’t skip the baby hat when you’re going out on a chilly day!