You shouldn’t scratch itching – why is it so good? Are there benefits?

You were told not to scratch this itching – but why do you feel so good? Scientists studying scratching found that although it worsens inflammation and swelling, it also has some benefits that can explain why the natural need seems so irresistible.

In the last test Published in the science magazine, scientists examined how itching affected the skin of mice with allergic contact dermatitis, a type of eczema.

“Srapie is often pleasant, which suggests that in order to develop this behavior must ensure some benefits. Our study helps to solve this paradox, providing evidence that scratching also provides defense against skin infections, “said the elderly author Daniel Kaplan in press release.

In the study, scientists used allergens that cause itching to cause signs of eczema in the ears of normal mice. While some mice could outline, others were limited from scratching with small collars, similar to those used by dogs.

The results were striking: mice they outlined developed swollen, lit skin filled with immune cells called neutrophilia, while people unable to scratch had much milder inflammation. This confirmed that scratching worsens skin irritation, not alleviate.

Scientists explain that this happens because scratching itching causes a chain reaction in the skin. Pain detecting nerves release chemicals called P, which activates mast cells or immune cells that regulate inflammation and itching. Usually, mast cells react to allergens, causing mild itching and swelling. But scratching causes a second wave of activation by substance P, intensifying inflammation and worsening itching.

However, mast cells not only cause irritation, but also help to defend bacteria and other germs. This caused that scientists are interested in whether scratching really affects the microbiome of the skin.

In further experiments, the team showed that scratching reduced the number of staphylococcus aureus, the most common bacteria involved in skin infections on the skin. “The discovery that scratches improves defense against Staphylococcus Aureus suggests that this may be beneficial in some contexts. But the damage that outlines the skin probably outweighs this benefit when itching is chronic, “said Kaplan.