Dr. Salim Surani explained why men are more susceptible to the flu and how women have greater resistance to influenza. "There are a couple of studies that show women having more local and systemic reactions to the flu shot than men," said Dr. Kyle Sue, author of the new study and an assistant professor of family medicine at Memorial University of Newfoundland in Canada. He added the evidence suggests that, overall, women may be "more responsive to vaccinations than men."