Diet in Relation to Health: Dark Adaptation as Index of Vitamin A Intake

Cutaneous Manifestations of Vitamin a Deficiency in Children

“…normal zone. Such an immediate response of the retina has been obtained also by Edmund and Clemmesen,1'1 Friderichsen and Edmund,17 Mutch and Griffith,18 Jeghers,6 Wald, Jeghers and Arminio 10 and Lewis and Haig,20 though not byHecht and Mandelbaum,21 and can be elicited only if an adequately large close of vita¬ min A is administered. When the preliminary series of tests shows that the deficiency is very marked or when the patient is an adult or nearly adult in size, a larger test dose such as 500,000 units should be used.In this connection we refer to the immediate response of even normal individuals to a single dose of 2,000,000 units of vitamin A as reported by Getz, Hildebrand and Finn 22.…”

Dark Adaptation in Pigmented Rats. The Effect of Overexposure to Light

“…In some earlier investigations, before the relation of vitamin A to dark vision was discovered, an overexposure to light was considered the principle cause of night-blindness (Netter 1863, Parinaud 1881, Graefe 1859, Forster 1875, Bondi 1922). Recently more emphasis has been placed on vitamin A deficiency, and exposure to strong light regarded as a releasing factor for hemeralopia when there is a vitamin A deficiency (Holm 1924, Fridericia and Holm 1925, Aykroyd 1930, Mutch and Griffith 1937, Trait6 d'Ophthalmologie 1939.…”

Night Blindness

“…Many workers mostly in America, Denmark and this country (Frandsen 1934, Jeans and Zentmire 1936, Jeghers 1937, Edmund' and Clemmesen 1937, Maitra and Harris 1937, Mutch and Griffith 1937 have attempted to evaluate the extent of vitamin' A deficiency in sections of the population by the examination of the dark adaptation of large numbers of individuals and have all come to the conclusion that there is a widespread failure to reach a satisfactory standard. Unfortunately the experimental procedure of much of this work is open to serious criticism and the results have not been confirmed by other workers whose investigations have been more carefully controlled (Ehlers 1937, Groth-Peterson 1938, Palmer 1938.…”