Protecting the head is very important from a health perspective. Results of medical tests show that 40-60% of body heat is lost through the head, so persons wearing head coverings during cold months are protected about fifty-percent more than those who do not.
Chinese and Muslim medical texts take this concept even further. In the Hua Di Nei Jing (The Yellow Emperor’s Classic on Internal Medicine), wind is said to cause sudden changes within the body, and shaking, swaying, and other movements that potentially upset the body’s equilibrium; thus, creating bad health. These texts attribute the common cold to wind elements entering the body and causing the typical symptoms of sneezing and a runny nose.
In the traditional Islamic medical texts of Al-Jawziyya, we can find numerous references to the "four elements" of fire, water, air, and earth, and how these affect the body in adverse ways. In particular, we are advised to stay away from drafts and to protect our heads in wind, breezes, drafts, and cold weather. All outdoor workers should wear some sort of head covering for this reason.
Protecting the head is even more important in warm weather. V.G. Rocine, a prominent brain research specialist, has found that brain phosphorus melts at 108 degrees; a temperature that can be easily reached if one stays under the hot sun for any length of time without a head covering. When this happens, irreversible brain damage, memory loss and loss of some brain functions can result. Although this example is extreme, brain damage can still be measured in small degrees from frequent exposure to and overheating of the head. Bernard Jensen, a naturopath and chiropractor, states that this is because the brain runs on the mineral phosphorus, which is very effected by heat.
Last, but not least, a veil or head covering should be worn by all public workers serving society to ensure cleanliness and purity. Workers in a number of professions wear "veils" - nurses, fast food workers, deli counter workers, restaurant workers and servers, doctors, health care providers, and many more. In fact, when we compare the number of workers who cover their heads to the number who do not, we find that more people probably cover their heads than do not.