Vitamins
It was not until the beginning of this century that it was recognized /that certain substances were essential in the diet to prevent or cure some diseases. / These substances are now known as vitamins. / They are vital for growth, good health,/ and maintenance of the normal functions of the body. / A well-balanced diet should provide all the vitamins we normally require. / Those of us who are fortunate enough to be able to buy sufficient food/ should not suffer from vitamin deficiency. / However, for various reasons,/ some people do not maintain a balanced diet. / People often lose their appetite because of illness. / People living alone may not bother to eat proper meals,/ and people on a diet may not eat sufficient quantities of necessary foods. / Moreover, modern methods of preserving, freezing and long-time storage of food,/ together with over cooking, can destroy many of the vitamins. / (145 words)
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