Summer is starting to wind down here in the northern hemisphere, which means that now is exactly the right time to start preparing your face (if you’re a man) for next year’s adventures in the Sun by growing nature’s sunscreen, a big bushy beard. In a recent study Alfio Parisi and colleagues shows that no question is beyond the scope of the scientific method: they seek to find out exactly how good beards and moustaches are at blocking ultraviolet (UV) radiation, the source of sunburns and skin cancer.
On her blog Neurotic Physiology, pseudonymous blogger Scicurious describes how the scientists equipped mannequin heads with various stages of beardedness and then left them outside in the sun for a few hours. The scientists found that their long beard, which was roughly 3.5” long, blocked more sunlight than their short beard, which was 1.5” long. Both beards, however, blocked way more sunlight than no beard at all, proving that beards not only look great, they also serve a useful function.
That being said, beards’ sun-blocking benefits can be offset by the fact that bacteria and viruses have an unnerving tendency to cling to facial hair, even when vigorously washed.
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