How to keep well in wartime
1943 1943 1940s 28 pages : illustrations CHOOSE THE RIGHT FOOD work out that in certain conditions a car will give a certain performance when petrol vapour undergoes combustion in the engine's cylinders. Part of the energy freed by the combustion moves the piston and the car "goes...
| Main Authors: | , |
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| Institution: | MCR - The Modern Records Centre, University of Warwick |
| Language: | English English |
| Published: |
London : His Majesty's Stationery Office
1943
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| Subjects: | |
| Online Access: | http://hdl.handle.net/10796/07AE5EDD-F802-45E8-AA2F-AF68B516CB9A http://hdl.handle.net/10796/4031954E-5CBB-411D-9A4F-51211E6C4493 |
| Summary: | 1943
1943
1940s
28 pages : illustrations
CHOOSE THE RIGHT FOOD work out that in certain conditions a car will give a certain performance when petrol vapour undergoes combustion in the engine's cylinders. Part of the energy freed by the combustion moves the piston and the car "goes ". Part of the energy is given off as heat, and this warms up the water in the radiator. The fuel for your engine is food. Combustion takes place inside the body. Part of the energy freed is used by your muscles and you "go". Part is given off as heat and warms your blood. The amount of energy that various foods will give can be exactly calculated. The amount of energy and heat you produce in your body can be measured. And it is easily proved that this energy and this heat come from the combustion of food and nothing else. You cannot, so to speak, create energy. Oxygen Feeds You, Too. Just as petrol vapour must be mixed with air for it to make the car go, so do you need air. For combustion to take place, oxygen is necessary. You obtain this from the air you breathe. The oxygen in the air which goes to the lungs passes into the blood. The blood carries the oxygen to every part of the body. Without oxygen — without combustion — the body cannot do its work, and so it dies. How the Body Burns up Sugar. If sugar is burnt outside the body it finally turns into water and carbon dioxide — the gas that gives the fizz to soda water. Exactly the same thing happens in the body. The carbon dioxide is carried by the blood to the lungs, and you breathe it out into the air. (Incidentally, plants use the carbon dioxide in the air as food for themselves.) Some of the water, too, is breathed out of the lungs. But water also leaves the body through the skin as sweat and by the bladder and bowels as urine and faeces. Combustion of sugar gives the body a quick supply of energy. When you do brain work — read, speak, or listen, for example — the cells in your brain burn up sugar, and for this they need oxygen. The oxygen is carried by the red corpuscles in your blood. If you have too few red corpuscles — if you are anaemic — then your brain may not get enough oxygen and therefore won't work so well. So, in a sense, oxygen is a food, and that is one reason why doctors want people to have plenty of fresh air in well-ventilated houses, offices and factories. In some illnesses doctors give the patient an extra amount of oxygen to breathe. Everyone Needs Starch. Sugar and starch are what chemists call carbohydrates. Starch is an important food. It is the chief stuff in bread, potatoes, and all cereal foods. During digestion it is broken down into sugar, which is a simpler chemical substance. So whether you eat starch or sugar it is all the same in the long run because they both enter the blood from the intestines as the sugar called glucose. But when you eat starch, for example, in the form of 9
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| Physical Description: | TEXT |