THE MINERAL REQUIREMENT 



331 



makes up a very large proportion of fresh fruits and vegetables ; 

 it is also present in large proportion in milk and eggs, is less 

 abundant in meats, and is lowest in dried foods and nuts. The 

 amount of water in a given food is often a decided factor in its cost. 



The mineral requirement. Minerals are quite as essential to 

 the body as energy foods and proteins. But it is only recently 

 that scientists have learned 

 how important a part is played 

 by minute quantities of cer- 

 tain mineral substances. For 

 example, the clotting of our 

 blood, without which we should 

 bleed to death from the small- 

 est cut, appears to depend 

 largely on the presence of cal- 

 cium in the blood. Lack of 

 calcium and phosphorus causes 

 stunted growth, soft bones, and 

 defective teeth, while a lack of 

 iron causes anaemia and other 

 disorders. If one will com- 

 pute the minerals in the diet 

 served in many homes, which 

 consists so largely of meat, po- 

 tatoes, and white bread, he will 

 easily see how lacking such foods are in the mineral essentials. 

 Fruits, vegetables, milk, and eggs are the best sources of all these 

 minerals. Meat contains iron, but is so lacking in calcium that a 

 large number of servings would be necessary to furnish the daily 

 calcium requirement. Milk is one of the most important sources 

 of calcium for the body and should be included in the dietary every 

 day. Other minerals are just as essential as these three, but are 

 not so likely to be lacking in the diet. 



Some salts, compounds of magnesium, potassium, and phos- 

 phorus, aid the body in many of its most important functions. 

 The beating of the heart, the contraction of muscles, and the 

 ability of the nerves to do their work appear to depend on the 



ounces in a 125 lb. person. 



calcium. 



29.6 



phosphorus 



19.9 



potassium 



6.9 



sulphur- 



4.9 



sod^ urn 



3. 



chlorine 



3. 



magnesium 



1 



iron 



.08 



iocCme 



trc*ce 



fluorine 



•t 



silicon 



•• 



trcanganese 



•• 



This diagram gives the probable amount of 

 minerals found in the body of a person weighing 

 123 pounds. 



