Evening Star Newspaper, July 5, 1931, Page 56

Your body is like a machine that is running all the time, and as it runs it produces & certain amount of heat. This heat comes from the transformations in matter that are ‘eonstantly going on in the human body. “Such changes in matter are always ac- companied by changes in energy oOr heat changes,” explains Dr. Francis G. Benedict, director of the Boston, Mass., Nutrition Lab- oratory of the Carnegie Institution of Wash- ington. Dr. Benedict has spent many Years studying these changes in thousands of men, women and children under different condi- tions, and has reached interesting conclusions. “The body is constantly changing,” he says. s«we cannot have life without these changes. Even if one is lying quietly asleep, still these changes are continually going on, vital changes, and it is important for us to realize that life jtself is the cause of these changes.” So you cannot stop the heat production of your body entirely in your efforts to keep cool. Some of this heat is required to keep the body machine running. Furthermore, as long as the body machine runs, even if it is throttled down to idling speed, it will con- tinue to produce some heat. However, you can keep the heat produc- gion down by diet and rest. Food is the chief fuel that keeps the body's fires going and makes life possible. NWHEN & man gets up from the dinner table after a good meal and lies down for a siesta, his heat production is at its highest, so far as the internal changes are concerned, for the effect of the digestive proce-esisnddtdtomahulcormmneeds for life,” Dr. Benedict explains. “If he goes for a walk, plays golf or bowls, his heat production or metabolism is much greater. “Digestion is & very important process. The heat production may be increased 40 per cent after a heavy meal, and the increase may jast from 10 to 12 hours, gradually lessen- ing in intensity toward the end of this time as digestion is finished.” Some foods produce more heat when they are burned than others, just as cosl makes & hotter fire than wood. The heat produced by food when it is burned in your body is measured by the calory. This familiar term is not & measure of tem- perature, but of energy or of heat. When one quart of water is heated s0 that its tem- perature is raised three degrees Fahrenheit, it will absorb about one calory of heat. In the process of heating anything, heat is absorbed, whereas in combustion, heat is given off. Two tablespoonfuls of sugar, for instance, produce 100 units of heat, or calories, when they are burned in your body. Dietitians and nutritionists sometimes classify foods as high calory or low calory foods. The high calory foods are those which are digested with great heat production. They are the foods you want to eat sparingly in hot weather. The low calory foods are di- gested with very little heat production, so you can fill up on them during the dog days. ‘ A MONG the high calory foods are meats, nuts, fats, sugars and starches. Veg- etables and fruits are low calory foods. Yce cream, one of the favorite hot weather foods of America, is not so cooling as it feels while you are eating it. It is made chiefly of sugar and cream, both of which belong to the high calory list of foods. Water ices are better hot weather eating, because, being made without cream, their caloric content is pot so high. Another factor which increases your heat production is the physical exertion you make, seientists have found. When you are resting im bed before breakfast, your heat production it at its lowest level. You are only produc- ing one calory a minute. If you sit up, the heat production increases somewhat, though pot very much. Moderately rapid walking, however, increases # bout 200 times, while violent exercise makes your body fires burn extremely fast with con- sequent enormous heat production. A foot ball player playing very hard produces about 600 calories in one hour, Dr. Benedict found. The same amount of muscular exertion in the ‘‘line of work produces a similar increase in heat production. Certain factors affecting your heat produc- fion are beyond your control, however. If THE SUNDAY STAR, WASHINGTON, D. C, JULY S5, MOSL Scientists of Carnegie Imstitution Have Measured the Human Body’s Heat- Making Machine and Found That Sex, Height and Weight All Have a Direct Influence on Your Abilities to Keep Cool in Hot Weather or to Keep Warm in * Cold Weather. Measuring a co-ed's basal metabolism rate. An experiment at Simmons College, Bosfon. On the cot, inhaling oxygen, is Miss Josephine Boli. The others are Elizabeth Kerr (left) and Norma Bianchi. you are a man, for instance, you cannot help having a higher heat than women, taking into account weight, height and age, which are other factors affecting this matter of body changes and accompanyimg produc- tion of heat and energy. “Women of the same height, age and weight as men would produce approximately 10 per cent less heat,” Dr. Benedict says. “Of course, the average woman is both shorter and lighter in weight than the average man, but these factors of weight, height and age can be equal- ized in a statistical analysis and the effect of sex clearly shown in an unmistakable manner.” This is one reason why men feel hotter in Summer but stand the cold better in Win- ter than women do. Metabolism is the technical name which sci- entists give to the process of changes or trans- formations of matter in the body. The rate at which these changes go on is called the metabolic rate. The rate varies between dif- ferent persons and is influenced by sex, age, weight, height, food and rest or physical ex- ertion. HE metabolic rate is determined by measur- ing the heat produced during metabolism. “This may be measured directly or indirectly, the latter method being simpler and more fre- oxygen needed to keep your body's fires going is obtained from the air you breathe. Scientists E i; i : ; : ] i i .gggg B:dl 1|F a man went 15 days without food, his heat production would be much lower sign. that there is some disturbance of his life wmncesses, which may perhaps be serious. ‘In other words, the measurement of his basal metabolism gives a fine, almost delicate index of the living, vital capacity of a man, a measure of his overhead needs for food and a good reference basis in case he is subsequently ill, and a disturbance of his metabolism is Some people find it harder to keep cool in Summer than others. They often tell you they feel the heat dreadfully because they are so warm-blooded. This is a mistaken motion. Un- less they are actually ill with fever, their blood is the same temperature as yours—98.6 degrees Fahrenheit. If these people feel the heat more than you do. it may be because their metabolic rates are higher. Their body fires are burning faster and they are producing more heat than you are. S50 naturally they feel hotter than you do. “If we compare two men of the same height, the heavier man will produce more heat than the thinner man of the same height,” Dr. Bene- dict says. “Thus we see that weight alone in- creases the heat production. “Height also raises heat production. Of two men of the same weight but of different height, the taller man will have a larger heat pro- You have probably noticed how old people seem to suffer more from the cold in Winter and how little they notice the heat of the dog days. That is because the body's fires burn slower in old age and older persons produce less heat in their own bodies. § " APS one of the most extraordinary and most interesting of the internal fac- tors affecting basal heat production is that of age.” Dr. Benedict pointed out in his report. “The heat production is lowered by age. A man, for example, at 25 years of age, in full prime of physical vigor, produces more heat than a man of the same height and weight but 70 years of age. The fires of life are burn- ing at & somewhat lower ebb in old age. “The influence of age is particularly striking in adolescence. Indeed, the influence of age may actusly counteract the rather considerable increase ift heat production due to weight and height. “Thus when we were studying groups of Girl Scouts who ranged from 12 years to 18 years of age, we found that as a result of their growing older they increased in weight and increased in height. both of which factors would normally tend to raise the metabolism. “But, as they were growing older, the age factor lowered the metabolism, and we found, singularly enough, that with all our Girl Scouts (and we measured some 150) the total basal expressed in terms of 24 hours about 1,250 calories, whether a girl was 12 years old or whether she was 18 years old.” When you have cut your heat production down to a minimum by eating carefully of low- calory foods and resting as much as possible, your next step in keeping cool is to provide for the most efficient way of losing what little heat you cannot help producing. You want to wear loose,” porous clothing which allows the heat generated by your 'body to pass into the air away from you. Why Women KEEP COOLER Than Men Am way of keeping cool is by perspir- ing. If you perspire a quart of water, you, have gotten rid of about 500 calories. Water can carry more heat without showing it than anything else in the world. Of course, you must drink plenty of water to replenish the supply in your body. If you_do not perspire much, you will be more comfortable in hot weather if you drink hot tea and coffee rather than the iced variety, as the warm drinks will induce extra perspiration. If the air already holds all the water ® can take up, you cannot get cool by sweat- ing off the heat, which is why & muggy day with high humidity is so uncomfortable. Omn such a day you must drive the hot, moist layer of air away from your skin, using a fan if there is no breeze available. If vou will add a pinch or two of salt to your drinking water in hot weather, you will find that it helps you to endure the heat. Sclentists investigating conditions in hot coal mines and steel plants, where men have to work under extremely high temperatures, found that the workers who succumbed rapidly when working in a temperature of about 100 degrees were able to stand it better when this small amount of salt was added to their drinking water. At high temperatures, espe:ially when one js working hard, the body gives off large amounts of water in perspiration. This is na- ture’s way of keeping one cool. However, the body also loses much salt with the perspira- tion—which is what causes a large part of the physical exhaustion you experience when you work hard in the heat. To overcome this, then, try putting a pinch of salt in your water. % NE of the keeping-cool rules advocated by science is to avoid th- use of alcoholic drinks in hot weathgr. / ohol serves as @& food as well as a thift-qv -her, scientific ex- periments have shown. W .en alcohol is burned in the body, it gives rise to heat and energy, like other foods. Consequently, such an alcoholic drin® as beer is by no means as much of a “cooling &rink™ as its consumers believe. While it is being consumed, of course, it gives a sensation of coolness. Later on, however, this effect wears away, and the beer drinker finds himself actually warmer than before. An experiment with goldfish carried out by Prof. W. E. Burge, L. D. Seager and D. J. Verda of the University of Illinois physiology depart- ment proved that alcohol also can perform an- other function of foods. It increases or stimu- lates the metabolic process by which the body converts food into heat and energy. In other words, then, when you take a long, cool drink with an alcoholic base, such as beer or a mint julep, you are really stoking your body's fireme making them burn faster and produce more heat, rather than checking the fires and cutting down the heat production. The same thing applies, in a different way, to some of the drinks you buy in a drug store soda fountain on a hot day. A chocolate malted milk, for example, may be deliciously cool and refreshing, but it has a considerable quantity of heat-producing food in it, and the metabolic processes of your body are stimu- lated to new activity as soon as you have con- sumed it. In the same manner, a heaped-up ice cream sundae may seem like just the thing to cool you off on a blistering Summer day, but it actually will help to increase your sensation of heat instead of diminishing it. As a matter of fact, pure water is about the best cooling drink of all. And, as was remarked above, if you try adding just a small pinch of salt to it when you have to work under espe- cially high temperatures, you will find that yom feel much more comfortable. Marylamd Produces Potash. THE potash producers of this country are mak- ing headway toward the time when the farmers of this country may be independent of foreign sources for this essential of a balanced fertilizer. Last year the production of potas- sium salts was over 100,000 tons, which was more than 10 per cent of the total require- ments of American users. The foreign monope oly no longer can hold the threat of high price or shortage for the American sources of sup- ply are onghe increase. At the present time the greater part of the potash produced here comes from distillery waste at petroleum refineries in Maryland and from natural brines of California. Some is mined in Nevada and Utah.