Scurvy cases (notably French soldiers eating fresh horse meat), it was discovered that meat alone, even partly cooked meat, could alleviate scurvy. Conversely, in other cases, a meat-only diet could cause scurvy. Scott's 1902 Antarctic expedition used lightly fried seal meat and liver, whereby complete recovery from incipient scurvy was reported to have taken less than two weeks. Hippocrates documented scurvy as a disease, and Egyptians have recorded its symptoms as early as 1550 BCE. The knowledge that consuming foods containing vitamin C is a cure for scurvy has been repeatedly rediscovered and forgotten into the early 20th century. In the
Vitamin D deficiency deficiency has been associated with urbanisation in terms of both air pollution, which blocks UV light, and an increase in the number of people working indoors. The elderly are generally exposed to less UV light due to hospitalisation, immobility, institutionalisation, and being housebound, leading to decreased levels of vitamin D. The reduced pigmentation of light-skinned individuals may result in higher vitamin D levels and that, because melanin acts like a sun-block, dark-skinned individuals, in particular, may require extra vitamin D to avoid deficiency at higher latitudes. The natural selection hypothesis suggests that lighter skin color evolved to optimise vitamin D