334 HOW DOES MAN DETERMINE THE VALUE OF FOOD? 



dread disease which could only be cured by a supply of fresh 

 vegetables or fruits. This deficiency disease has been found to 

 be caused by a lack of vitamin C. Experiments carried on in the 

 Japanese navy about 1882 showed that beriberi, a serious menace 



prevents 

 beri-beri 



/protects lungs /\\«D 

 cmdC prevents M\\ 

 e/e disease 4T\^ 



prevents 



scurvy 



prevents g~\ f\ T% prevents 

 peUccgTer fjr/fci\ |J rackets 



prevents sterility 

 in, rett/5 



Why are vitamins essential to the diet ? 



to health among oriental peoples, is caused by a lack of some 

 substance that is not present in the rice and fish which form the 

 major part of their diet, for when milk and vegetables were added 

 to the diet, beriberi disappeared. Later experiments showed that 

 the lack of vitamin B caused beriberi. A lack of vitamin D has 

 been found to be one of the causes of rickets, a disease of chil- 

 dren, " characterized by impaired nutrition and alterations in the 

 growing bones." Very interesting is the fact that rickets can be 

 cured by exposing the patient to the direct rays of the sun. The 

 rays that have curative value are the so-called ultra-violet. These 

 rays do not pass through ordinary window glass, but will pass 

 through quartz or " vita glass." More interesting still is the fact 

 that certain foods (such as cottonseed oil which contains no 



