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 A can be represented as two connected retinyl groups, which are used in the body to contribute to vitamin A levels. Alpha-carotene and gamma-carotene also have a single retinyl group, which give them some vitamin activity. None of the other carotenes have vitamin activity. The carotenoid beta-cryptoxanthin possesses an ionone group and has vitamin activity in humans. Vitamin A can be found in two principal forms in foods: Vitamin A deficiency is estimated to affect approximately one third of children under the age of five around the world. It is estimated to claim the lives of 670,000 children under five annually.