Allergies and asthma on the rise

Asthma and other allergic diseases, such as hay fever and food allergy, have become more common in the last several decades. The reasons behind this are a hot topic for researchers. Strategies for promoting clean living environments and preventing infections actually may be to blame. Large studies show children from environments that inevitably expose them to more bacteria and viruses, such as farms, day cares and large families, have fewer asthma and allergies. Conversely, when exposed to fewer infections and germs in early life, the immune system tends to develop allergies and asthma more easily. More research into this “hygiene hypothesis” suggests some exposure to dirt and infections is required for normal immune system development in childhood. Don’t throw out the vacuum yet though, since researchers admit that this hypothesis does not completely explain the rise in allergies and asthma.