CALORIE; symbol C.; a heat unit and food value unit; is that amount of heat necessary to raise one pound of water 4 degrees Fahrenheit.
There is a good deal of effort expended by many semi-educated individuals to discredit the knowledge of calories, saying that it is a foolish food science, a fallacy, a fetish, and so forth.
They reason, or rather say, that because there are no calories in some of the very vital elements of foods—the vitamines and the mineral salts—therefore it is not necessary to know about them. They further argue that their grandfathers never heard of calories and they got along all right. That grandfather argument always enrages my mortal mind.
A Unit of Measure
Now you know that a calorie is a unit of measuring heat and food. It is not heat, not food; simply a unit of measure. And as food is of supreme importance, certainly a knowledge of how it should be measured is also of supreme importance.
Yes, They Are Kosher
You should know and also use the word calorie as frequently, or more frequently, than you use the words foot, yard, quart, gallon, and so forth, as measures of length and of liquids. Hereafter you are going to eat calories of food. Instead of saying one slice of bread, or a piece of pie, you will say 100 Calories of bread, 350 Calories of pie.
The following is the way the calorie is determined:
An apparatus known as the bomb calorimeter has two chambers, the inner, which contains the dry food to be burned, say a definite amount of sugar, and an outer, which is filled with water. The food is ignited with an electric connection and burned. This heat is transferred to the water. When one pound of water is raised 4 degrees Fahrenheit, the amount of heat used is arbitrarily chosen as the unit of heat, and is called the Calorie.
Food burned (oxydized) in the body has been proved to give off approximately the same amount of heat or energy as when burned in the calorimeter.
1 oz. Fat = 275 C.
—about 255 in the body.
1 oz. Protein (dry) = 120 C.
—about 113 in the body.
1 oz. Carbohydrates (dry) = 120 C.
—about 113 in the body.
Can you see now why fats are valuable? Why they make fat more than any other food? They give off more than two and one-fourth times as much heat, or energy, as the other foods.
Notice that protein and carbohydrates have the same food value as to heat or energy, each 113 Calories to the dry ounce. However, they are not interchangeable; that is, carbohydrates will not take the place of protein for protein is absolutely necessary to build and repair tissue, and carbohydrates cannot do that. But fats and carbohydrates are interchangeable as fuel or energy foods.
Calories Needed per Day for Normal Individuals
Business of Growing
This depends upon age, weight, and physical activities; the baby and the growing child needing many more calories per pound per day than the adult, who has to supply only his energy and repair needs. The aged require still less than the young adult. As to weight; I have told you why overweight individuals need so little. As to physical activities; the more active, obviously the more calories needed, for every movement consumes calories.
Many Know Nothing of This
The Maine lumbermen, for instance, while working during the winter months, consume from 5000 to 8000 Calories per day. But they do a tremendous amount of physical work.
Mental work does not require added nourishment. This has been proved, and if an excess be taken over what is needed at rest (if considerable exercise is not taken while doing the mental work) the work is not so well done.
Calories Required for Normal
Infants require 40-50 C.
Growing Children 30-40 C.
Adults (depending upon activity) 15-20 C.
Old age requires 15 or less C.
In Round Numbers for the Day
Child 2-6 1000 to 1600 C. per day
Child 6-12 1600 to 2500 C. per day
Youth 12-18 2500 to 3000 C. per day
(Remember that in general the boy needs as much as his father, and the girl as much as her mother.)
MAN (per day):
At rest 1800 to 2000 C.
Sedentary 2200 to 2800 C.
Working 3500 to 4000 C.
WOMAN (per day):
At rest 1600 to 1800 C.
Sedentary occupations (bookkeeper, etc.) 2000 to 2200 C.
Occupations involving standing, walking, or
manual labor (general housekeeping, etc.) 2200 to 2500 C.
Occupations requiring strength (laundress, etc.) 2500 to 3000 C.
Example of Finding Number of Calories Needed
1. Determine normal weight by rule.
2. Multiply normal weight by number of calories needed per pound per day.
For example, say you weigh 220 or 125 lbs., but by the rule for your height your weight should be 150 lbs.; then 150 would be the number you would use.
Work Out Your Requirements
By the rule I have given, adults require 15-20 Calories per pound per day, depending upon activity. For example, if you have no physical activities, then take the lowest figure, 15. 150×15—2250. Therefore your requirement, if your weight should be 150, is 2250 Calories per day.
Now, if you want to lose, cut down 500-1000 Calories per day from that.
Five hundred Calories equal approximately 2 ounces of fat. Two ounces per day would be about 4 pounds per month, or 48 pounds per year. Cutting out 1000 Calories per day would equal a reduction of approximately 8 pounds per month, or 96 pounds per year. These pounds you can absolutely lose by having a knowledge of food values (calories) and regulating your intake accordingly. You can now see the importance of a knowledge of calories.
1 lb. fat 4000 C
1/2 lb. fat 2000 C
1/4 lb. fat 1000 C
1/8 lb. fat 500 C
If you want to gain, add gradually 500-1000 Calories per day.