Foods may be valued in accordance with the cost of their constituents as compared with the cost of the same constituents in bread and margarine, taken as standards, or on the basis of the number of heat or energy units or Calories1 which these foods provide for a given sum of money. Neither method is perfect, but the latter is the more useful of the two, and that which is generally adopted in arriving at the energy value of all foods. We can compare the cost of starch, which is the chief food material in rice, macaroni, oatmeal, or any other cereal, with the cost of starch in bread, but we cannot make an equally close comparison between the protein of meat or cheese, or of the fat of butter or lard, with the protein or fat in bread, for obvious reasons. The protein of bread is not utilised by the system so perfectly as the protein of meat, while the fats in butter, lard, and bread possess varying market values weight for weight, hence margarine is a better standard for fat.

1 A Calorie (the standard employed in measuring the heat value of foods) indicates the quantity of heat required to raise 1 lb. of water 4° F.

If we take bread as a standard, and value it in units, we shall find a penny will buy 600 when the cost is 2d. a pound. When rice costs a similar sum, a penny buys 800 units, but immediately the price rises to 3d. a pound the units purchased by this sum fall to 533. Again, a piece of beef of medium fatness, costing 10d. a pound, provides 850 Calories to the pound, so that a penny buys only 85 Calories, and it is in this way that we are able to estimate the economical value of different foods by this particular system. A poor man who is led to believe that by the purchase of a cheap joint of lean meat, to be eaten with bread and potatoes, he can feed his family with greater economy than with food of a much simpler character, may find that while he is spending more money he is providing considerably less nourishment. Let us illustrate this fact with a ration consisting of 3 oz. of meat at 1s. a pound, 3 oz. of bread, and 4 oz. of potatoes per head of a family consisting of a man, his wife, and three children.

Ration I

The above provides a liberal supply of protein, but in order to make it equal to the following ration it would be necessary to increase it in quantity by 75 per cent., when its cost would amount to 2s. 2d. Thus, while in one case the ration would amount to nearly 5d. per head, in the other it would cost only l 7/8d. In other words, the second ration, while providing over 60 per cent. more nutritive matter than the first, would cost less than the meat in that ration.

Ration II

This ration, which can be varied in a hundred ways, is intended to demonstrate the economical side of nutrition. The cost of meat, and its low nutritive value, must ever prohibit that variation and liberality in providing a repast, where it is regarded as an imperative dish, in the homes of those who have little to spend. I am happily connected with a philanthropic institution in which the children and staff were fed before the war with great skill and generosity at a cost of 2s. 9d. per head per week. They maintain wonderful health, and as a group are models of what growing children should be in their physical, moral, and intellectual life - a large number of the old boys going to the front in the early days of the war. These results are owing to the generous allowance of foods, of which meat forms a very small portion, to exceptional skill in its arrangement, and the personal care of the lady superintendent, who regulates every detail.

The Arrangement Of Rations Or Meals

We have seen that while it is important that we should obtain a sufficient quantity of each of the four groups of food constituents in what we consume, we should not eat too much of either. Apart from the question of nutrition altogether, there is a limit to the quantity which can be eaten without sickness or harm, although that limit may vary with age, occupation, or constitution. The young can eat sugars and fats, as in sweetmeats and cream, with a degree of impunity, where adults, and still less those who have passed middle age, dare not make the attempt. It is important to recognise that a meal should consist of mixed foods. This ensures more perfect digestion, and as a rule establishes an approximate equilibrium or balance between the various constituents. Thus, if at dinner the dishes consist of a small plate of meat or fish, potatoes, a green vegetable, wholemeal bread, a cereal pudding, with preserved or fresh fruits, the consumer, eating rationally, obtains an ample supply of all the necessary nutrients, while at the same time he is providing the mechanical help without which no ration is perfect.

If, however, for reasons of economy, meat is omitted, its place may be taken by fish, some varieties of which are much cheaper, or, better still, by a third vegetable in the form of dried or preserved peas, beans, or lentils - unless the two former can be purchased green and fresh, and are equally cheap. These three foods are not only much richer in protein than lean meat or fish, but they contain large quantities of starch. Where, too, meat at 1s. a pound provides only 60 to 100 units of energy for a penny, according to its fatness, the pulses referred to provide 550 when their cost is 3d. a pound. It should be added, however, that the protein of vegetables, and especially of the pulses, is less perfectly absorbed during digestion than the protein of meat.