It seems that everyone has heard that you lose most of your body head through your head, and because of this, you should always wear a hat in winter weather. This advice can be traced back to a US army survival manual from 1970 which states that “40 to 45 percent of body heat” is lost from the head. Evidently this was based on a scientific experiment by the US military in the 1950s where volunteers were dressed in Arctic survival suits and exposed to bitterly cold conditions. Their heads were the only part of their bodies left uncovered which resulted in the greater proportion of heat loss.
Recent tests have shown this belief to be false, and that essentially all exposed body parts lose heat equally. Most likely, because our face and head are more sensitive to changes in temperature, it feels as if covering them up does more to prevent heat loss. In my experience, covering my head, neck and shoulders gives me the most comfort in cold environments. Similarly, I can’t help but think about how I place a newly created coal low in a tinder bundle so that it builds heat above it to assist in creating a flame. So, if heat travels upward, I’ll want to capture it. Failing this, I’ll fall back on the “mind over matter” rule… if you don’t mind, it doesn’t matter.