Ah-Choo! Men suffer more from colds and flu than women

Long-suffering men around the world have been the victim of jokes about “man flu” and their inferior ability to soldier on through the sniffles compared with women. But according to European scientists, it might be true that men suffer more from colds and flu. Dr Beatrix Grubeck-Loebenstein, an immunologist at the University of Innsbruck in Austria, has been researching gender immune differences for a long time.
Her findings give solace to men who feel that women don’t take their superior suffering seriously. “Grossly simplified, it can be said that men, due to the differences in the immune response, can become ill more often than women,” says Grubeck-Loebenstein.
As she explains it, pathogens that invade the body are attacked by immune cells that can be specific or non-specific. The former are effective only against particular pathogens — a flu virus, say — and enable the body to defend itself against a wide variety of viruses, bacteria and parasites.
However, there are relatively few of each type of specific immune cell. To destroy an invading pathogen, it must multiply a million fold. This is where gender differences come in: While the female hormone oestrogen aids in the multiplication of specific immune cells, the male hormone testosterone does the opposite.
“Oestrogen stimulates the immune system. Testosterone, on the other hand, suppresses it,” says Dr Marcus Altfeld, head of the virus immunology research unit at the Heinrich Pette Institute in Hamburg, which investigates the biology of human pathogenic viruses.
“Women’s immune systems therefore react faster and more aggressively to pathogens than men’s.”
What’s more, the higher a man’s testosterone levels are, the weaker his immune system is. So “real men” have it rougher.
Researchers are unsure of the reasons for the gender differences. Since the human immune system has developed over millions of years, Altfeld notes, we need to look far into the past for a possible explanation.
“Our Stone Age ancestors lived in caves and were exposed to dangers. The purpose of the female immune system then, as now, was especially to protect the unborn or newborn child,” he says.
Grubeck-Loebenstein, too, links women’s immune response with childbearing: “The effect of the oestrogen-strengthened immune system is especially pronounced in young women after puberty and becomes weaker in women after the menopause.”
Men’s greater susceptibility to many illnesses isn’t solely due to their testosterone-weakened immune system, though, she says. “Other factors — behavioural and environmental — play a role as well. Men still take more risks, have unhealthier diets and are less disciplined about vaccinations.”
— dpa