^CALCIUM METABOLISM IN OLD AGE AS 

 RELATED TO AGEING OF THE SKELETON 



O. J. Malm, m.d., R. Nicolaysen, m.d., and L. Skjelkvale 



Inst, for Ernceringsforsking, Oslo. 



Ageing of the skeleton implies dissolution of structural 

 units (osteons and trabeculae) with loss of calcium salts from 

 the body and with a reduction of the breaking strength. It is 

 not known if the breaking strength is always proportionate 

 to density of mineralisation. 



The systematics of bone diseases have been discussed in a 

 number of text books and monographs, for example Albright 

 and Reifenstein (1948). 



Senile osteoporosis is said to be frequent in old age, but no 

 good statistics have been produced. The problem is how, if 

 at all, this disease is related to dietary intake of calcium and 

 vitamin D. Further, the course of calcium metabolism is not 

 known during the development of the disease; but it must be 

 negative over a period of years. 



Recently, the problem has in part been ably discussed by 

 Hegsted, Moscoso and Collazos (1952), who consider that the 

 calcium requirement of adult man is low and that the frequent 

 occurrence of osteoporosis is not related to calcium intake. 



On the other hand numerous discussions of the Ca require- 

 ment of man have ended with a recommendation for a defined 

 intake. Lately the U.S. Food and Nutrition Board revised 

 their recommendation of 1 g. to a rninimum of 0-8 g. daily 

 for adult men. The implication must be that adult people 

 consuming considerably less Ca than is recommended run 

 the risk of getting into continuous negative Ca balance which 

 in the course of time must lead to recognizable osteoporosis. 



Such differences of opinion can only be settled by adequate 



♦This is to be considered as a preliminary report, presented by 

 Prof. Nicolaysen. 



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