## The Graphic Method

"Different foods contain the three food elements, proteids, fats and carbohydrates, in different proportions. The tripartite constitution of any particular food is represented in the present method by the position of a point in the triangle CPF (Fig. 1). The method of locating the point on the triangle is analogous to that of locating a city on a map by latitude and longitude; the per cent of proteid in the food is represented, like latitude, by the height of the point above the base line CF (the total height, CP, being taken as 100 per cent). The percentage of fat is represented like longitude, by the distance of the point horizontally from the vertical line CP (the total horizontal breadth, CF, being taken as 100 per cent). Thus, the point 0, representing milk, is located at a height above CF ('latitude') 19 per cent of the total height of the triangle, which signifies that 19 per cent of the food value of milk is proteid; and at a distance to the right of CP Clongitude') 52 per cent of the total breadth of the triangle, which signifies that 52 per cent of the food value of milk is fat. Foods high in proteid will be represented by points high up in the triangle. White of egg, of which the food value is all proteid, will be represented at the point P, representing 100 per cent. P is, therefore, called the 'proteid corner' of the triangle. Foods rich in fats, as nuts, cream, and butter, are represented by points far to the right. Pure fats, like olive oil, are located at F at the extreme right, representing 100 per cent of fat. F is therefore called the ' fat corner'.

"The point representing a food is completely located by means of the percentage of proteid and fat; no attention need be paid to the carbohydrate. If one desires a graphic representation of carbohydrates it is found in the distance of the point 0 from the third side of the triangle, FP the total distance of this side from the opposite corner being taken as 100 per cent). Foods like bread, cereals and fruits, which are mostly carbohydrate, will thus be represented by points far away from the side FP. Foods such as sugar, of which the food value is wholly carbohydrate, will be represented at the remotest point C, representing 100 per cent carbohydrate, which is, therefore, called the 'carbohydrate corner'.

Fig. 1. " Food Map." Composition of Milk Represented by Position of Point O.

Figs. 2 and 3. "FOOD MAPS".

Figs. 4 and 5. "FOOD MAPS".

"Any food is thus represented on the ' food map' by a point, the relative distances of which from the three sides of the triangle represent the proteid, fat and carbohydrate. On this food map, fatty foods are represented by points near the fat corner, F; starchy and saccharine foods by points near the carbohydrate corner, C, and proteid foods by points near the proteid corner, P. A food devoid of proteid is evidently located on the base line C; a food devoid of fat, on the side CP, and a food devoid of carbohydrate on FP. The chief classes are represented in the accompanying diagrams, flesh foods and cereals being shown in Figure 2; dairy products, eggs and meat substitutes in Figure 3; vegetables in Figure 4; nuts and fruits in Figure 5; soups, salads and relishes in Figure 6, and puddings, pies, pastries and sweets in Figure 7. In each case the position of the point relatively to the sides of the triangle represents the proportions of the proteids, fats, and carbohydrates, and the number opposite each name represents the weight (in ounces) of a 'standard portion.' * * *