Food Health and Income: Appendix 1 The basis of calculation: Per Head and Per Man Value units

The data on consumption and requirements were arranged on a per head instead of a per “man value ” basis. The man value of any individual is the ratio of that individual’s normal calorie requirement to the calorie requirement of the average moderately active man taken as unity. Thus the man value of the average moderately active woman, whose calorie requirement is commonly estimated as four-fifths that of the average moderately active man, may be taken as 0.8. The man values of children are smaller or larger than unity according to age and according to the particular scale of man value adopted. There are at least thirty-eight such scales.

The object of this investigation is to present an economic survey of the food habits of the country, and consequently the cost of supplying fully health-maintaining diets to individuals of both sexes and all ages is necessarily one of the most important bases of the investigation. The use of any man value scale based on calorie requirements would have led to an underestimation of the cost of feeding children, since foods rich in first-class protein, vitamins or minerals, of which the requirements are greater for growing children than for adults, are the more expensive. Stiebeling (44) has drawn up tables showing the relative cost of food for different individuals in terms of the cost of the diet of the moderatively active man. Thus the cost of feeding a boy 11-12 years old is only 11 per cent, less than the cost of feeding a moderatively active man an adequate diet, while for an active boy over 15 years old it is 17 per cent. more. The cost of feeding an infant alone is clearly less than that of an adult, but on the other hand the nutritional requirements of the nursing mother are much greater. The difference between the cost of feeding an infant compared with an adult is partly counter­balanced by the extra cost of giving the mother a fully adequate diet, which would enable her to breast-feed her infant.