Sunlight as Man’s Ally Against Illness

Sun (Auckland), Volume II, Issue 580, 5 February 1929, Page 13

Sunlight as Man’s Ally Against Illness

! Gaiety and Vivacity Are Its Effects DESTROYS GERMS ! The beneficial influence of sunlight in relation to health has only comparatively recently been scientifically explained, states a paper issued by the Department of Health. We have sometimes been apt to fear it rather than to welcome it; to think of the danger of sunstroke and the power of the sun to fade carpets and curtains rather than to recognise that it gives health and vigour to the body and destroys germs of j disease. Provided that there is proper protection of the head and nape of the neck from a very hot sun, the more children play in the sunlight and the more we let sunlight into our rooms at home and at school the better. In large towns much of the sun’s energy is cut off, only about onequarter of it getting through the atmosphere as compared whh onehalf at the seaside and three-quarters on mountain-tops. Some of the beneficen influence of sunlight is due to invisible rays. A beam of sunlight when passed through a prism or through the drops of a shower of rain, is divided up into its constituent parts and we see the seven

primary colours of which sunlight is composed (as in the rainbow), starting with red at one side and ending with violet at the other. The invisible special health-giving rays are found beyond the violet rays and are called ultra-violet rays. Unfortunately, these rays are filtered out when sunlight passes through window glass, and this is one of the reasons why being indoors is not so health-giving as being out of doors. Advantage is taken of the health-giving properties of sunlight, especially of these ultraviolet rays, to treat debility and other ailments. Its healing properties are utilised in the treatment of children suffering from such diseases as rickets and tuberculosis of the skin, bones, and joints, by heliotherapy in the open air, or artificially by the arc lamp. Injury Done by Smoke

The harm done by the smoke pall which hangs over large cities, particularly in densely populated countries and by fogs which occur with greater or less frequency, blocking out the sunlight from homes, schools and streets, is due partly to the acids, carbon, and tarry matters in the smoke which injure vegetation, corrode buildings, make houses dirty, or choke the lungs. Under such conditions there is a tendency to keep windows closed, to prevent unclean atmosphere and dirt coming in. Atmospheric smoke obstructs the actinic rays of the sun more in towns than in the country or the seaside. The ultra-violet rays of the sun, which have especially important effects on animal and vegetable life are readily absorbed by atmospheric impurities, dust, smoke, and the like, and will not even pass through ordinary glass which absorbs them. They are not apparent to our senses, and their presence can only be ascertained b ythe observance of the effects which they produce. Their biological significance lias been so abundantly manifested that it is a matter of serious important that they are so readily absorbed by the smoke-pol-luted atmosphere of towns. Effects Of Sunlight

Humanity is singularly sensitive to the effects of light, and the tonic or stimulating influence of sunlight must be apparent to the least observant, states Sir Henry Gauvin, M.D. This eect is reflected in the gaiety and vivacity which follow exposure. Exercise on a clean, cold sunny day elicits our immediate reeVnse. The stimulus of light if over prolonged may, however, lead to exhaustion and fatigue. Evidence has been produced not only that sunlight or ultra-violet light derived from artificial resources has a psychological effect as shown by the increased vivacity of the subject exposed, but that “it is also a stimulus if not too long pressed, to mental activities; a point of considerable importance in education and indicating the desirability of well ighted as well as well ventilated rooms.

Sun Bathing

While sun treatment may be of much value to the sick it is perhaps not sufficiently appreciated that it is even of greater potential value to the healthy. Much of the benefit of a summer holiday is due to sensible exposure to sunlight and fresh air. To the healthy but overworked adolescent or adult the benefit of the properly planned sun bath can hardly be exaggerated. At the seaside ultraviolet radiation is intensified by reflected light from the sea and sea bathing preceded or followed by exposture to the sun is of great value. Lengthy exposure at the beginning of a holiday should always be avoided. Freckled or sandy-haired blondes should be especially careful. Short exposure of a few minutes, gradually increased, as the skin becomes brqnzed, to perhaps half an hour is all that is neded. Blistering or even undue reddening of the skin is harmful. The sun-bather should be energised and exhilarated after exposure. Fatigue, lassitude, irritability and headache are signs of over-exposure. Each individual is a law to himself and liis own feelings form an admirable guide.