The effects of life-long subsistence on diets providing suboptimal amounts of the “Vitamin B complex”

Abstract

1. A comparative study has been made of the life history of two groups of rats, one of which (483 animals) was maintained on an adequate diet whilst the other (556 animals) was given a ration providing a suboptimal intake of “vitamin B”. The chief defect of the second diet was probably in respect to vitamin B₁.2. The duration of life was shortened and reproduction was adversely affected by the deficiency.3. The examination of the post-mortem records provides clear proof of a significantly greater incidence of gastro-intestinal lesions, particularly ulcerations, in the animals on the deficient diet than in the control group.4. The deficiency of B₁did not influence the incidence or the severity of the chronic lung infection (bronchiectasis) common in laboratory rats.5. The incidence of all other disorders was about the same in the two groups.6. No evidence of increased susceptibility to tumours, malignant or innocent, was shown by the animals on the deficient diet. Cancerous developments arising at the site of chronic inflammatory processes (e.g. worm cysts in the liver, caecal ulcers of long standing, etc.) were not appreciably more numerous in one group than in the other.