322 



THE FOODS WE EAT 



of water a day, especially upon arising and between 



meals. 



The Value of Minerals in the Diet. A chemical analysis 



of the human body shows that it is made up of about 72 



per cent oxygen, 13.5 per 

 cent carbon, 9 per cent 

 hydrogen, 2.5 per cent 

 nitrogen, and about 3 per 

 cent of various mineral 

 salts. Chemically, then, 

 the body is composed of 

 the same substances as the 

 food on which it feeds. 

 Mineral salts, although pres- 

 ent in such minute quan- 

 tities, have been found to 

 be absolutely necessary for 

 life. If the body does not 

 get sufficient iodine, the 

 thyroid gland, found in the 

 front of the neck, is likely 

 to enlarge and form a goiter. 

 Iodine is found in some 

 natural drinking water and 



Everything that is alive or has had life 



contains some water. Make a list of 



foods that you think contain a large 



amount of water. 



in 



others. It is also 

 in foods such as 

 clams, oysters, and fish that 

 come from the ocean. 



Lime or calcium is needed for building bones and carrying 

 on certain processes in the body. For example, without 

 the presence of calcium our blood would not clot, and 

 we might bleed to death from even the slightest wound. 

 Milk, carrots, and some fruits, especially prunes and 

 oranges, contain a good supply of calcium. Iron is found 

 in the red blood cells, and lack of it causes people to 



