In ancient times a lot of attention was paid to the effects of various types of foods. Modern dieticians, besides doing the same also study the effects of not eating different kinds of foods. These are two aspects of the same problem. Here is a simple case. We come across a highly irritable man and want to find out why he is so.
Investigations reveal vitamin A deficiency.
Again, there has to be 90 to 110 mg of sugar for every 100 cubic centimeters of body volume. Slight deficiency causes emotional disorders. The man becomes ill-tempered and in extreme cases can even become a murderer. Modem science has proved that ill-temper and the murderous tendency are caused by a deficiency of sugar, niacin and certain vitamins. Chemical deficiency can cause depression.