How many times have you told your child that they need to wear a hat because they lose most of their heat through their head? But, is that really true? Do kids lose 75 percent of their body heat through their head, or is it just a myth?
The myth about heat loss through the head is very specific. It states that kids lose 75 percent of their body heat through their head, so they better put on that cozy cap. But the myth is untrue. Although heat is lost through an uncovered head, the percentage is closer to ten percent.
Where Did the Myth Come From?
Although no one can really be sure exactly where the myth that kids lose 75 percent of their body heat through their head came from, the source seems to be the military. In a 1970 survival manual, the U.S. Army recommended covering the head with a hat as a means of preserving body heat. The manual stated that a hat was important because “40 to 45 percent of body heat is lost from the head.” But that simply isn’t so say experts.
Another possible source for the myth that kids lose 75 percent of their body heat through their head is a 1950s military study that researched Arctic survival suits. Subjects in the study wore thermal suits but no hats and were exposed to frigid Arctic-like temperatures. Researchers reported that the subjects lost a great deal of heat through their heads.
Could Infant Head Sizes Be to Blame?
Still another possible source of the myth that kids lose 75 percent of their body heat through their head has its root in infant head size. So goes the theory, since an infant’s head size is so much bigger in proportion to the rest of their body when compared to adult heads, there is more heat loss through an infant’s head. This may have a grain of truth to it. The bigger the surface area, the more heat loss which is why hospitals cover newborn heads. But the percentage of heat loss would be nowhere near 75 percent. Also any exposed area be it arms, legs, feet or the head will cause heat loss.
Dispelling the Myth
If the results of the Arctic experiment sound like proof positive that it is true that kids lose 75 percent of their body heat through their head, think again. Experts say that the experiment had serious issues that affected the results. The only body surface subjects left uncovered was their head, so of course that’s where they lost most of their body heat. Had the subjects worn less clothing their loss of body heat would have been evenly distributed over their entire body. Had subjects worn say, a swimsuit, heat loss from their head would still only have been about 10%. If subjects had only left their feet uncovered, then that would have been the body part where most of the heat would have been lost.
Where is Most Body Heat Lost?
So if the myth that people lose 75 percent of their body heat through their head is not true, then where does the human body lose the most heat? Any uncovered or unprotected body surfaces will lose heat, whether that is the head, the arms or the hands. To avoid heat loss, it is important to cover the body, but no more heat will be lost from an uncovered head than uncovered arms or legs.
Parental Considerations in Colder Temperatures
So if the myth that kids lose 75 percent of their body heat through their head is false, then what should parents focus on when helping their kids retain body heat in cold temperatures? Experts agree that all exposed body surfaces should be protected during frigid temperatures. It is especially important to protect the face, head and chest as these body areas are more susceptible to temperature changes. However, covering any part of the body is equally effective and important in preventing heat loss.
So if it’s cold, bundle your kids up. That includes any part of their body that may be exposed. Remember, that hat will help keep their body heat in, but so will wearing gloves, scarves and boots.
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