People can get dermatitis, for instance, when they come in contact with mosquitos, snails, lice, poison ivy, poison oak, or when they have dry skin or staph infections. Skin conditions like psoriasis, eczema, and sunburn can also increase the itchy factor. Finally stress and too frequent use of antibacterial soaps can also increase the scratchiness quotient.

What causes our need to itch?

Put simply, some of our nerves are responsive to itchiness. Histamine, the protein released in our bodies during an allergic reaction, tells our itchy nerves to send information to the spinal cord, and, ultimately, the brain. Our brain activates certain sites in our brain; these are similar to the ones which are activated when we’re in pain.

Antihistamines (commonly prescribed for allergies and itches) ‘turn off’ the signal from the skin’s surface to the brain. New research says there are other types of nerve-itchy fibers than just the histamine ones, and that these recently discovered fibers may be responsible for the itch associated with more chronic conditions.

This new research suggests that people may scratch because, by doing so, this stimulates pleasure systems in the brain.

Too much scratching, though, can leave your skin broken, bleeding, and unable to provide its normal barrier to the environment.

So the point of the story? A little scratching is ok, too much is not.