Scurvy observed in any organism apart from humans and had been considered an exclusively human disease. Certain birds, mammals, and fish are susceptible to scurvy, but pigeons are unaffected, since they can synthesize ascorbic acid internally. Holst and Frølich found they could cure scurvy in guinea pigs with the addition of various fresh foods and extracts. This discovery of an animal experimental model for scurvy, which was made even before the essential idea of "vitamins" in foods had been put forward, has been called the single most important piece of vitamin C research. In 1915, New Zealand troops in the Gallipoli
Vitamin A a result of alcohol consumption during pregnancy is the elucidated mechanism for fetal alcohol syndrome and is characterized by teratogenicity closely matching maternal vitamin A deficiency. A 2012 systematic review found no evidence that beta-carotene or vitamin A supplements increase longevity in healthy people or in people with various diseases. A meta-analysis of 43 studies showed that vitamin A supplementation of children under five who are at risk of deficiency reduced mortality by up to 24%. However, a 2016 Cochrane review concluded there was not evidence to recommend blanket Vitamin A supplementation for all infants between one and six months