Does vitamin C help prevent the novel coronavirus?

Vitamin C supplements are reportedly in clinical trials in Wuhan to help cure the novel coronavirus pneumonia, so the public is wondering whether it helps to have vitamin C at home to prevent the disease. 

According to Ruan Guangfeng from China Food Information Center, the saying that vitamin C helps improve immunity originates from people's knowledge about colds, which is scientifically groundless. There is no proof that vitamin C relieves or cures colds.

Ruan said it is not necessary for healthy people to take extra supplements to prevent the disease as long as they get enough nutrition from a balanced diet. 

As for those who stay at home during the epidemic control, Ruan suggests taking vitamin C if fresh vegetables and fruit are temporarily unavailable - 100 milligrams for adults and no more than 200 milligrams for those who are pregnant.

Vitamin C supplements are not an alternative to fresh food, he said.