Study finds 'man flu' may be real because of lack of estrogen

LOS ANGELES -- In a recent study released in the American Journal of Physiology, researchers found that "man flu" could be real as men suffer more from the sickness than women because of their lack of estrogen.

Researchers said the female hormone actually protects women from the more aggressive symptoms of the illness. The team took nasal cell cultures from men and women, exposing both cultures to the influenza virus and estrogen.

The estrogen reduced the virus in the female cells, but not in the ones from men. The findings could lead to using estrogen to help fight the flu.