Neglected Areas of Nutrition Research 179 



when the rat is a young adult about six months old. Most 

 atteni})ts to keep rats free from this disease by moistening 

 food, spraying the air with antise])ties, having peo])le wear 

 masks in the rat room and the feeding of antibioties have 

 failed. The feeding of antibiotics does not even protect the 

 teeth of the rats from decay. Some success has been claimed 

 against this lung disease if young are transferred to healthy 

 mothers at the time of birth but no evidence has been pro- 

 vided that such rats can escape the disease during the latter 

 half which is the second year of life (Nelson, 1953). 



Rats retarded in growth when fed small amounts of high 

 quality diets delay the onset of this disease until control 

 animals have died with it under conditions that are commonly 

 termed old age for rats. This has made one pathologist 

 suggest that only those who have studied rats subjected to 

 retarded growth have ever seen rats with normal spans of 

 life. This might suggest that all experiments that have not 

 involved growth retardation have merely dealt with fore- 

 shortened life-span. 



This introduces the problem of misleading titles of articles 

 commonly found in the literature. Such titles often imply the 

 lengthening of life by some drug or system of feeding. Thus, 

 a diet may lack vitamin A and rats fed this diet may die 

 prematurely. The author may give this article the title of 

 "Lengthening of life by vitamin A" whereas he really means 

 the premature death of animals deprived of this vitamin. 

 Statements based upon such titles lead to erroneous con- 

 clusions in the literature. 



A second source of weakness in a science of old age based 

 upon research with white rats is what Sir Thomas Browne 

 might have called a "vulgar error". Some laboratories 

 compare diet A with diet B in regard to the mean span of life 

 of white rats fed upon these diets. Often little attention is 

 given to pathology or other data that could be derived from 

 the study. Conventional statistical testing of the means is 

 reported and the basic data are never published. Since such 

 studies require at least three years of time and cost much 



