It now seems well established that there are two distinct factors concerned in the Fat-Soluble A vitamin. One is antirachitic. The other is antixerophthalmic and growth promoting, and retains the appellation vitamin A.
The bony lesions following a dietary regimen in which the antirachitic factor has been lacking have been described.1 Among other lesions resulting from this deficiency, Kauffman, Creekmur and Schultz2 have described changes in the middle ear resulting in varying degrees of deafness. Grieves3 also claims that dental caries is another manifestation of the upset in calcium metabolism.4 There has also been mentioned in connection with rickets of a certain type an upset in nervous equilibrium due to an improper calcium balance,1 while Reynolds and Macomber5 assign to the same cause some cases of sterility.
The absence of vitamin A from an otherwise adequate diet will cause a cessation of growth soon followed by the characteristic eye lesions