Heat—The proper temperature of the body is between 98 and 99 degrees Fahrenheit. Human life depends upon the maintenance of this temperature at all times, and very slight changes either up or down interfere seriously with all the other life processes. The main source of heat is from food consumed, or really burned, in the body. Artificial heating in houses helps conserve the body heat, as does clothing. But clothes and shelter may make you overheated, which is nearly as bad as being cold; they may also shut out fresh air. Clothes should not be too heavy nor too tight. Shoes should have soles straight on the inner side, and be broad enough to allow the toes full play, and have low heels. Shoes that are comfortable to hike in are apt to be the best for all the time wear.
At night the clothes worn during the day should be aired and dried thoroughly. This will help much in maintaining the right body temperature, because clothes become damp from wearing, and dampness uses up body heat.
Sunlight—Sunlight is one of the best health bringers known. Little children—and grown people, too—suffering from the most serious forms of tuberculosis, that of the bones, get well if they are kept in the sunlight. In one of the finest hospitals for children in the world, in Switzerland, the main treatment is to have the children play outdoors without clothes in the sunlight, and they do this even when there is heavy winter snow on the ground. Human beings droop and die without the sun, just as plants do, though it takes longer to kill them. It is a gloomy person who does not feel happier in the sun, and a happy and cheerful person is generally healthy. So get into the sun whenever you can. Walk on the sunny side of the street, and open your windows to the sun whenever you can. However, in hot climates and in the warmest summer days, remember that the sun can injure as well as help, and do not expose the head or body unnecessarily.
Water—As about three-quarters of our body weight is water, the solid portions of bone, muscle, and so forth, constituting only one-quarter, and as considerable water is given off each day by evaporation from skin and lungs and with excreta, the loss must be made up. In addition to the water taken with meals and contained in the food a Girl Scout should drink at least six tumblers of water daily. This is a quart and a half. One glass should be taken on arising and before breakfast, two between breakfast and lunch, two between lunch and dinner, and one before going to bed. Be sure the water is pure, and boil any water the purity of which is doubted in the slightest. Water kept cool in the ice chest, or in a jar with a moist cover, is better than ice water, both because cool water actually quenches thirst more easily, being more readily absorbed than ice cold water, and because it is difficult to control the purity of ice.
Food—Food should be clean and kept clean. Growing girls can tell whether they are eating enough of the right sort of food, and if they are getting the best out of it, by seeing whether they are up to the right weight for their height and age. A chart is given at the end of this section showing the standard weight for each height at each age. The following are good rules to follow in making your daily food habits:
Do not eat between meals.
Eat slowly and chew food thoroughly.
Eat freely of coarse cereals and breads.
Eat meat only once a day.
Have green vegetables, salad or fruit every day.