26 



1916 ANNUAL REPORT 



predominate should be so balanced by foods having a predominance of 

 bases that the diet as a whole may yield sufficient fixed bases to neutralize 

 the mineral acids produced in its metabolism." 



The foregoing thus indicates the value of the generous use of fruits 

 and vegetables in the diet. Previous to the investigation of the importance 

 of the mineral matter, the value of fruits and vegetables was considered 

 more of a hygienic nature and the fruits themselves more as luxuries. Nuts 

 belong to the foods which furnish the acid-forming elements in excess 

 and therefore the wisdom of the combination of fruit and nuts. 



An investigation just completed in the Nutrition Laboratory at the 

 University of California, shows that the avocado belongs to that class 

 of foods which yield an excess of the base-forming elements. This was 

 perhaps to have been inferred, but until the investigation was completed, 

 no definite conclusions could be drawn. Four different analyses were 

 made, the varieties examined being the Taft and Sharpless furnished by 

 C. P. Taft and B. H. Sharpless, respectively, and seedlings from Messrs. 

 C. P. Taft and W. A. Spinks. There is evidenced a close agreement be- 

 tween the results of the specimens tested. 



More than one-half of the ash of the avocado consists of soda, potash, 

 magnesium and lime, the latter occurring, however, in comparatively 

 speaking small amounts, the phosphoric acid averaging about 17.5 per 

 cent, with 1.5 per cent of iron. 



In the ash of the cereals, nuts, meats, eggs, etc., the phosphoric acid 

 greatly predominates. This element is found in the avocado, on the 

 other hand, as in other fruits, only in relatively small amounts. In view 

 of the low content of lime, therefore, it could not be said that the avocado 

 should be recommended as furnishing any notable supply of bone ma- 

 terial. This, however, is not the function of the avocado. Its great value, 

 as far as mineral matter is concerned, lies in the fact that the ash con- 

 tains a predominance of bases such as sodium, potassium, magnesium, and 

 calcium. 



Another advantaige which may be cited in favor of the avocado is 

 that its content of ash is far higher than that noted for any other fruit. 

 The pure ash of the edible portion of the avocado shows an average con- 

 tent of 1.05 per cent, while those of the other fruits are as follows: 



Grapes 500 



Prunes 565 



Plums 524 



Apricots 484 



Nectarines 490 



Figs 440 - .897 (av. .600) 



Lemon 535 



Orange 500 



The olive is not included in this list for the reason that the ash of 

 the olive is high but due mainly to the salt with which it is pickled. In 

 other words, the olive is a processed fruit which cannot be eaten in the 

 fresh state and therefore one might say does not belong to the same 

 class as the avocado. 



It is true that if we were to compare the fruits above listed and the 



