1917] POODS HUMAN NUTRITION. 465 



milled products, they will die within a month or two of polyneuritis, a disease 

 very similar to beri-beri." 



As it is impossible to determine the vitamin content of cereal products by 

 isolation of these substances from the natural foods, the authors suggest the 

 use of the total phosphorus content as a fairly accurate index of the relative 

 amounts of vitamins present. While this method does not yield absolute values 

 of the vitamin content of cereal products, it is proposed provisionally for wheat 

 flour, corn meal, and hominy, that " for corn products the minimum PjOs con- 

 tent should not be below 0.5 per cent, that of wheat flour not lower than 1 per 

 cent." 



Attention is called to the use of baking soda in the preparation of bread as a 

 factor involved in the reduction of the vitamin content of bread, especially corn 

 bread. The authors state that when sodium bicarbonate is used as a leaven- 

 ing agent the high temperature of the oven liberates carbon dioxid from the 

 sodium bicarbonate and the latter is tran.sformed into sodium carbonate. Ex- 

 periments by the authors and others have shown the destructive action of 

 alkalis on vitamins, which lose their physiological activity when exposed to 

 alkalis, especially at high temperatures. It is stated that " corn bread made 

 from old-fashioned (whole) corn meal, sweet milk, and soda, when forming the 

 exclusive diet of chickens, leads to symptoms of polyneuritis, whereas corn 

 bread prepared from corn meal, sweet milk, and salt (NaCl) does not give 

 rise to any symptoms, and fowls seem to live in perfect health. Chickens which 

 have developed polyneuritis on the corn bread made with sweet milk and soda 

 are cured by the administratior. of vitamins prepared from various foods. 

 Hence ... [it may be concluded] that corn bread prepared by means of baking 

 soda without the addition of buttermilk is deficient in certain essential ac- 

 cessory foods (vitamins) and that this deficiency is due to the destx-uctive 

 action of the alkali (baking soda) on the vitamins which were originally con- 

 tained in these foods." 



If, however, sour milk or tartaric acid is combined with the baking soda to 

 neutralize its alkalinity, the use of baking soda is deemed harmless. The 

 authors also state that while the use of baking soda without sour milk will not 

 always prove injurious, bread s^ made is undoubtedly deficient in vitamins, 

 and when the other dietary compcneuts are also deficient in vitamins the com- 

 position of bread made with baking soda without the use of sour milk ac- 

 centuates this dietary deficiency and may lead to an impairment of health. 



Among the factors stated as playing a role in the reduction of the vitamin 

 content of the diet of the people of Spartanburg County are the decrease in 

 the consumption of the more expensive foods, such as meat, eggs, and milk, 

 which are rich in vitamins and efficient in the prevention and treatment of 

 pellagra ; the increase in the consumption of highly milled corn meal and 

 wheat flour; and the use of baking soda in the preparation of bread and its 

 addition to beans and other foods to soften them and shorten the time of 

 cooking. 



A study of the dietary conditions of certain communities showed " that a 

 large proportion of the people, especially in mill villages, live on a diet which 

 is deficient from the point of view of its vitamin content. Wheat biscuits 

 made from highly milled wheat fiour and corn bread made with baking soda 

 without the addition of buttermilk are the staple articles of diet among the 

 people, and . . . [families were found] in v/hich these foods represented about 

 three-fourths of the entire diet. The fact that the above-mentioned influences, 

 which have undoubtedly reduced the vitamin content of the diet, made them- 

 selves felt a relatively short time before the rapid increase in the pellagra in- 



