172 EXPEEIMENT STATION EECOED. 



In general, the autlior concludes that the use of average figures for computing 

 the composition of food may involve a considerable amount of error, but that 

 the calculation of the energy value gives results which are in fair accord with 

 actual determinations. According to his studies, the diet of an adult Finnish 

 peasant engaged in moderately severe muscular work supplies some 4,000 cal- 

 ories, while that of a woman at moderate work supplies 2,700 or 2,800 calories. 

 The diet of a 2 or 3 year old child supplies 1,000 calories per day, with an 

 increase of about 200 calories for each year's increase in age. On an aver- 

 age, the diet of an adult man supplies 136 gm. protein, 83 gm. fat, and 580 gm. 

 carbohydrates per day, and is made up chiefly of flour or other cereal products 

 and potatoes with small amounts of meat, fish, or bacon, and milk. On an 

 average, 84 per cent of the protein, 90 per cent of the fat, and 95 per cent of the 

 carbohydrates of the diet are digested. Variations in the diet in different 

 regions, methods of preparing food, and other similar questions are considered. 



Proteins: The relations between composition and food value, E. F. Aem- 

 STKONG (Ri)t. Brit. Assoc. Adv. Sci., 1909, pp. 4.5.9-.J6i). — The author sums up as 

 follows his paper presented at the 1909 meeting of the British Association for 

 the Advancement of Science : 



" When discussing the value of foods it is not enough to know merely the 

 gross amount of nitrogen-containing matter, but the nature and proportion of 

 its constituent units must also be taken into account. The ideal diet should con- 

 tain as great a variety of proteins as possible in order to provide a sufficient 

 amount of all the required units of constructive metabolism." 



A comparative study of the dig'estibility of natural and fermented milk 

 by adults, F. Samarani {Ann. R. Staz. Sper. Caseif. Lodi, 1909, pp. 35-106, 

 dgm. 1; ahs. in Rev. G6n. Lait, 8 {1910), No. 1^, pp. 328-332 ) .—Experiments 

 were made with man and animals, the general conclusion reached being that, 

 considered from the standpoint of its digestibility by adult man, fermented milk 

 possesses physical-chemical characteristics which render it superior to natural 

 milk. 



The digestibility of milk preparations by man, K. Thomas (Arch. Anat. u. 

 Physiol., Physiol. Aht., 1909, pp. Jfl7-Jf29; abs. in Chern. ZentU., 1910, I, No. 

 25, p. 2021). — The author was himself the subject of experiments on the di- 

 gestibility of whole milk, casein, milk curd precipitated with rennet, dried skim 

 milk, and a dried preparation made from whole milk and kefir. Precipitated 

 and finely divided casein was more completely digested than whole milk. The 

 dried milk preparations were as well assimilated as fresh milk. The kefir 

 showed a higher resorption of fat than natural milk. 



Concerning potassium metabolism, E. Biernacki {ZentbL Gesam. Physiol. 

 M. Path. Stofftuechsels, n. ser., 5 (1910), No. 11, pp. 401-^08). — The author dis- 

 cusses potassium metabolism and reports the results of investigations on this 

 subject. 



If the amount of sodium chlorid in the diet is increased, the potassium ex- 

 cretion is also increased, and vice versa. He concludes therefore that under 

 the infiuence of large doses of sodium chlorid the body can lose corresiwndiugly 

 large quantities of potassium. He also concludes that there is hardly any 

 doubt that when the body weight increases there is a tendency for the potassium 

 excretion to increase, and such an increase usually takes place. This has an 

 obvious relation to the theory that has been advanced regarding the role of 

 potassium in the organism with reference to carbohydrate metabolism, lower- 

 ing the potassium content of the body and consequently diminishing the 

 carbohydrate cleavage being naturally related to fat formation and gains in 

 weight. 



