220. Obesity

Obesity, or the excessive accumulation of body fat, is an occasion of great discomfort to many persons. The intense desire of the excessively corpulent to be freed from this condition has opened the way for the sale of "fat cures" that mostly deplete the store of cash rather than of adipose tissue.

Table XXXV. Energy And Food Requirements Of A Man (70 Kilograms Weight With Clothing) For Different Kinds Of Muscular Work

Energy and Food Requirements of a Man (70 Kilograms Weight with Clothing) for Different Kinds of Muscular Work1

MUSCULAR WORK FEB HOUR

Energy Expenditure per Unit of Work

Increase of Metabolism during One Hour's Work

Cal.

Gms. Fat used up

3.6 kilometers over level road .

40.3 per km.

144

16

6.0 kilometers over level road .

47.2 per km.

283

30

8.4 kilometers over level road .

78.6 per km.

660

70

6.0 kilometers over level road, with 25 kilogram load. . .

64.1 per km.

385

41

4.8 kilometers over level road with 25 kilogram load. . .

59.3 per km.

285

30

Climbing 300 meters (30 per cent gradient; easy climb) . . .

49.0 per 100 m.

147

16

Climbing 300 meters, stiff climb (over 30 per cent) ....

58.0 per 100 m.

174

18

Ascent of stair - 300 meters in a distance of 3000 meters - 10 per cent rise

89.0 per 100 m.

267

28

9 kilometers cycle ride on level road

20.3 per km.

183

19

15 kilometers cycle ride on level road

20.8 per km.

313

33

22 kilometers cycle ride on level road

25.9 per km.

571

60

9 kilometers cycle ride with 3 per cent ascent

38.3 per km.

345

36

15 kilometers cycle ride on level road, with a head-wind of 10 meters per second ....

40.1 per km.

601

64

1 "Metabolism and Practical Medicine," Von Noorden, Vol. I, p. 229.

It seems reasonably certain that in a large percentage of cases the cause and cure of obesity are entirely within the control of the afflicted individual. With many obese persons, perhaps a majority, the laying on of excessive fat is the result of a disparity between the food consumed and the energy expenditure. In other words, certain individuals, especially men in the professions not requiring physical activity and those doing office work at a desk, eat more than is needed to sustain the energy expenditure. It is noticeable that when an individual becomes less active without diminishing his food he grows fatter, and the same occurs with an increase of food without a corresponding increase in the physical activity.

The remedy for obesity with individuals whose metabolism is normal is either less food or more exercise. A reduction in the food taken may require a rigorous control of appetite, especially at first, but after a time the eating habit will probabJy become readjusted. A material increase in physical exercise will accomplish the same result as a decrease of the food taken.

It does not now seem possible to explain all cases of corpulency on the basis of overeating or deficient physical exercise. These instances where very corpulent persons maintain their weight without loss on an amount of food less than the customary requirement for such individuals, laying on of fat by animals on which castration or ovariotomy has been performed, and the influence of life conditions with women, seem to indicate a modified metabolism.

Studies of such cases of obesity have so far failed to establish the fact of abnormal life processes, for the use of oxygen (energy exchange), protein metabolism, and digestion appear to have been normal. An explanation of all cases of obesity does not seem to have been reached.