Chapter 3 - You And Your Calories

Food Is Your Fuel | How Weight Is Gained and Lost | How You Spend Your Calories | Your Weight and Your Basal Calories | Your Height and Your Basal Calories | Your Age and Your Basal Calories

Everybody talks and worries about his calories, but how many of us understand them?

Whatever else we humans may be, we're warm-blooded. Even our most primitive ancestors knew that warmth meant life, a cold body meant death. Our bodies are like radiators —somewhat more attractive to be sure—but similar in that warmth flows from them to the colder surrounding atmosphere. For this reason our bodies burn foods which supply units of heat known as calories.

To be precise, a calorie is that quantity of heat necessary to raise a kilogram (about thirty-five ounces) of water 1°C. Fortunately, for this discussion we don't have to be that precise about it. We need only know that we take in calories as food. We use the calories up as muscular energy and heat dissipation. Incidentally, we're now discussing "large calories," which are 1,000 times greater than those you might have come across in the physics laboratory at school. In some ways the body is like a coal-burning locomotive. When coal burns in an engine, it creates heat, measured in calories, which converts water to steam. This steam produces the power that turns the locomotive's wheels. Thus neat has been converted to work.

Food Is Your Fuel

Your body uses food as its fuel. When this fuel burns, heat, measured as calories, maintains body temperature and circulation. Just as steampipes in a home carry heat to all the rooms, your blood carries heat-producing nutrients to all parts of your body. This furnishes the energy required by your vital organs and by your physical and mental activities. As with the steam engine, heat has been converted to work. Besides supplying the calories for energy, foods are utilized to repair and replace your burned-up body tissue.

The processes associated with the growth and repair of tissue and the conversion of foodstuffs into usable energy are known as metabolism. Men have a higher metabolism than women. They require about 20 per cent more food and burn up their calories faster. For that reason women can gain weight more quickly than men.

If you take in more calories than you use, you deposit fat to your credit (or discredit). If you use up more than you take in, you burn a part of your fat reserve and lose weight. If intake and output remain the same your weight remains constant.

How Weight Is Gained And Lost

Alice R. is our exhibit A. A thirty-five-year-old housewife, living in the city, 5 feet 5 inches tall and weighing 130 pounds, she expended an average of 2200 calories per day in housework, walking to market, and weekend recreation. But her daily food consumption averaged 2315 calones, making a net gain of 115 calories. Multiplying this 115-calorie-per-day surplus by 30 days, her monthy gain amounted to 3450 calories. Since a pound of body weight equals about 3500 calories, Alice began to add about one pound each month.

At this point her living habits underwent a slight change. Instead of walking she drove her automobile to market. During weekends she substituted canasta for outdoor recreation. Mechanical gadgets cut down her household chores and, with them, her calorie cost of work. Her energy expenditure dropped from 2200 to 1950 calories per day, but her work at the dining table continued at the same level.

Although her eating had not increased, this lessening of activity swelled her daily surplus by 250 additional calories, or 7500 per month. This amounted to another 2-pound weight gain. Off she went to her family physician.

In brief, here's how Alice reduced to her desirable weight. Her doctor prescribed a 1700-calorie diet. Then she resumed her daily walking and weekend exercise, which restored her 2200 calories of energy. This 500-calorie daily deficit amounted to the loss of about a pound a week. Slowly but surely and safely Alice's fat was utilized by her body and disappeared. She had corrected what her physician called her metabolic imbalance.

How You Spend Your Calories

Your total calorie output consists of several elements. First, there are the basal calories. These are the calories required to keep you alive when you lie quietly in bed, neither exerting yourself nor eating. This condition of total rest would seem to be the height of laziness, involving no energy whatever. Actually, about two-thirds of your total food intake is utilized to provide sufficient heat for your body in this state. These basal calories make up for your continuing heat loss. In addition they supply the energy with which your heart muscle pumps blood, your lungs inhale oxygen and expel carbon dioxide, your food is digested, your brain functions, your kidneys manufacture urine, and your liver performs its chemistry. You cannot cut your basal calorie needs. They maintain your body temperature and circulation and even help you meet emergencies by supplying epinephrine.

Besides basal calories, your total calorie output consists of calorie expenditures for work and for environmental response. Under the latter heading would come such activities as shivering as you undressed in a cold room.

In the good old days, enormous amounts of food were required to make up for the heat lost in vigorous physical activities and in inadequately heated homes.

The Maine lumberjack could consume a monumental 6000 calories per day without gaining weight. The New England farmer savored a tidy breakfast of eggs, waffles, sausage cakes, apple pie, coffee and cream without developing the trace of a paunch. When the old-timer undressed in the cold, his metabolism shot up 60 per cent, and when he shivered it helped boost his calorie expenditure to a new high. We nonshiverers expend only about 2100 calories a day in the warmth of modern living.

With insulation, better clothing, and today's heating systems, the number of calories we need for our maintenance has diminished, but it still accounts for two-thirds of our normal food requirements.

The remaining food consumption provides us with fuel for such activities as dressing, rushing to the bus, arguing about a raise in salary, lowering ourselves into a comfortable chair, turning the pages of a book, or, more likely today, turning the dial of a television set.

You must increase the amount of food burned to whittle away at body fat. Since tampering with basal calories is a dangerous business, our best bet is to work on our activities. One of the major objects of this book is to expose the myth that exercise is of no value in the reduction of weight.

The key to successful dieting is the elimination of small increments of food and the addition of small increments of exercise, and by exercise I don't mean push ups, bar bells, or water polo. I mean the normal exercise of daily living which all too often we tend to ignore in this mechanical age.

We'll come to exercise later. Meanwhile we want to find out why different people have different basal calorie needs.

Your Weight And Your Basal Calories

The amount of skin surface on your body is one of the chief factors in determining your daily food requirement. The greater your skin area, the more heat you radiate and lose and hence the more food you burn to produce this heat. Fat people have more skin surface area exposed to the atmosphere than people of desirable weight who are of the same height, age, and sex. Hence they must consume more food than people of normal weight merely to maintain their bodies at normal temperature. Their obesity increases their bodies' metabolic requirements and forces their pancreas, liver, and endocrine glands to work harder. In this vicious cycle the overweight individual must eat excessively. He overworks his whole metabolic system just to maintain his obesity.

The tables below illustrate this important point. They show how your weight affects the number of basal calories you require during a twenty-four-hour period. As examples I have chosen a thirty-five-year-old man, 5 feet 10 inches tall, and a thirty-five-year-old woman, 5 feet 2 inches tall. Note how the number of calories they require rises with each increase in weight:

Thirty-Five-Year-Old Man

Height                 Weight                               Basal calories in 24 hr.

5'10"                   100                                    1470
                           125                                    1600
                           150                                    1730
                           175                                    1840
                           200                                    1970
                           225                                    2060
                           250                                    2180
Thirty-Five-Year-Old Woman

Height                 Weight                               Basal calories in 24 hr.

5’2”                    90                                      1180
                           100                                    1240
                           125                                    1360
                           150                                    1470
                           175                                    1580
                           200                                    1680

The 200-pound woman requires 500 calories a day more to maintain her weight than the 90-pound lady. But if our 90-pounder became ravenously hungry and began eating the quantities required by the heavier woman, she would ultimately weigh 200 herself.

The tables above have shown that the more you weigh, the more calories you require to stay alive. It is also true that the more you weigh, the easier it is to burn your calories. Did you know that in walking a mile

A 100-pound man expends 63 calories?

A 150-pounder expends 85 calories?

A 200-pounder expends 106 calories?

A 250-pounder expends 127 calories?

Your Height And Your Basal Calories

Height, as well as weighs is an important factor in your basal calorie needs. If we were all tall, our lives would be much less complicated. Besides being able to watch parades and tower above ladies' hats in the theater, we could eat rather heavily without gaining weight. Our elongated skin surface would enable us to dispose of much of our food by the radiation of heat.

As specific examples of the effect of height on daily food requirements, let's take the cases of a thirty-five-year-old man who weighs 150 pounds and a thirty-five-year-old woman who weighs 125 pounds. Note how their calorie requirements rise with each increase in height.

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Thirty-Five-Year-Old Man

Weight                      Height                          Basal calories in 24 hr.

150                           5'                                 1550
                                 5'4"                              1620
                                 5'8"                              1700
                                 5'10"                            1730
                                 6'                                 1770
                                 6'2"                              1810

Thirty-Five-Year-Old Woman

Weight                Height                             Basal calories in 24 hr.

125                     4'11"                               1290
                           5'2"                                 1360
                           5'6"                                 1420
                           5'8"                                 1450

It's clear from this that the shorter person has a greater problem keeping his weight down to its desirable level.

Remember that we are now talking about basal calories, the heat we require just to stay alive. These figures do not take into account differences of activity or occupation.

Your Age And Your Basal Calories

Your age, as well as your height and weight, plays a key role in determining your daily food requirements. As I have mentioned, virtually all the simple obesity of the middle-aged and elderly results from a continuation of the same eating habits through the years although one's activities have slowed. In addition, your metabolic requirement is automatically lessened with the passage of years. A newborn baby requires 75 calories per day per pound of body weight, but a woman of sixty-five requires only 15 calories per day per pound. This is a fact few people recognize. Even if you were able to lead as active a life at sixty as at sixteen, your food requirements would be less. Alas, a sixty-year-old gentleman indulging in touch football or a high-school dance would burn fewer calories than a sixteen-year-old. He might fool his playmates and his dancing partners, but he could not fool his metabolism.

Here are two tables which demonstrate the effect of age on basal calorie needs. We've chosen a 5-foot 10-inch, 150-pound man and a 5-foot 2-inch, 125-pound woman to demonstrate. Note how their calorie requirements for a twenty-four-hour period lessen as they grow older.

5-Foot 10-Inch, 150-Pound Man

                        Age                           Basal calories in 24 hr.

                        14-15                        2020
                        16-17                        1890
                        18-19                        1800
                        20-29                        1730
                        30-39                        1730
                        40-49                        1690
                        50-59                        1650
                        60-69                        1600
                        70-79                        1560
 
5-Foot 2-Inch, 125-Pound Woman

                        Age                           Basal calories in 24 hr.

                        14-15                        1600
                        16-17                        1490
                        18-19                        1410
                        20-29                        1370
                        30-39                        1360
                        40-49                        1340
                        50-59                        1300
                        60-69                        1260
                        70-79                        1230

The food you eat takes care of your basal calories plus your work calories. We've seen the effects of weight, height, and age on basal calories. Now let's examine the calories you require for your activities.

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