As soon as we begin to chew our food, a juice in the mouth, called saliva (sa lī´vá), moistens and mixes with it.
Saliva has the wonderful power of turning starch into sugar; and the starch in our food needs to be turned into sugar, before it can be taken into the blood.
You can prove for yourselves that saliva can turn starch into sugar. Chew slowly a piece of dry cracker. The cracker is made mostly of starch, because wheat is full of starch. At first, the cracker is dry and tasteless. Soon, however, you find it tastes sweet; the saliva is changing the starch into sugar.
All your food should be eaten slowly and chewed well, so that the saliva may be able to mix with it. Otherwise, the starch may not be changed; and if one part of your body neglects its work, another part will have more than its share to do. That is hardly fair.
If you swallow your food in a hurry and do not let the saliva do its work, the stomach will have extra work. But it will find it hard to do more than its own part, and, perhaps, will complain.
It can not speak in words; but will by aching, and that is almost as plain as words.
SWALLOWING.
Next to the chewing, comes the swallowing. Is there any thing wonderful about that?
We have two passages leading down our throats. One is to the lungs, for breathing; the other, to the stomach, for swallowing.
Do you wonder why the food does not sometimes go down the wrong way?