Unfortunately however the concept of 'seasonal' food has practically disappeared today. There was once an expression, "when the watermelon rind falls into the sea". For when watermelon appeared on the market, it meant summer, and the swimming season, had arrived. What a pity that the younger generation today has no idea which fruits and vegetables are grown in which season. In one of his books, respected medical historian Henry E. Sigerist explains that there is no sharp line between food and medicine from the standpoint of their effect on human metabolism. Widespread research is being done today on the impact on human health of the nutritional elements in food, and scientists are saying that some foods can even be used as drugs to treat certain diseases. Owing to human negligence, many therapeutic foods are unfortunately becoming degraded today. Such degradation aside, some species have even been wiped out completely. The truth is that man is only going to acquire a healthy lifestyle when he learns to live in parallel with nature.