There are two major epidemics in this country going on at the same time — asthma and obesity.

Are they connected? We don’t know for sure — but here’s what we do know.

A number of studies have shown that more heavy folks have asthma symptoms than thin folks. A number of studies have shown the association is greater in women than men, and may only apply to women.

Even in childhood, heavier females have a stronger association with asthma than men. A study of 1,000 children found the incidence of asthma symptoms with being heavy occurred only in girls.

The relationship between asthma and obesity in women is highest among those who have their periods early, which suggests a role for hormones in heavy asthmatic women.

A number of studies have found that heavy women who lose weight do improve their asthma.

We don’t know why asthma and obesity are related, especially in women. There may be some hormonal factors, and other factors may also play a role. We need more research on the topic and more work on both illnesses.