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Is It Possible To Be Too Clean?

Being clean is a good thing.

After all, simply washing your hands regularly can help ward off flu and other contagious diseases.

Is It Possible To Be Too Clean?


For the past few decades scientists have been debating the so called "hygiene hypothesis"--the idea that being exposed to a wide range of microbes early on helps strengthen the immune system.

According to the hypothesis, too much anti microbial cleanliness at a young age can throw the immune system out of whack, causing it to overreact later on.

Good Bacteria

Now, a study lends support to this idea. Scientists have found that bacteria living on our skin help prevent cuts from becoming inflamed when the immune system reacts to the wound.

The immune system is only trying to help, of course. When we get cut a cut or wound, immune cells rush to the area to fend off foreign particles that might cause infection. And some inflammation is inevitable. But too much inflammation is bad--it can cause diseases like rheumatoid arthritis.

Immune System And Hygiene Hypothesis

So according to the study, skin bacteria dampen the immune cells' activity enough to prevent excessive inflammation without hampering the immune system's ability to fight infection.

This doesn't prove the hygiene hypothesis, exactly. But it does show that bacteria on, and maybe in, our bodies help the immune system do its job without going out of control.

Read More: Dirt Can Be Good For Children, Say Scientists (

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