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 D deficiency outcome for some cancers, but evidence is insufficient to recommend that vitamin D be prescribed for people with cancer. Taking vitamin D supplements has no significant effect on cancer risk. Vitamin D, however, appears to decrease the risk of death from cancer but concerns with the quality of the data exist. Vitamin D deficiency is thought to play a role in the pathogenesis of non-alcoholic fatty liver disease. Some studies have indicated that vitamin D deficiency may play a role in immunity. Those with vitamin D deficiency may have trouble fighting off certain types of infections. It has also been