Why we sometimes can’t resist picking scabs: Blame it on our ape ancestors

Why we sometimes can’t resist picking scabs: Blame it on our ape ancestors

In CNA Lifestyle’s ongoing series on bad habits, we look at scab-picking. One reason why people do it could be a slight addiction to the mild pain it creates, says an expert. Read below on how to help your skin heal faster.

Illo for picking scab
(Art: Jasper Loh)

It’s gross to anyone who catches you in the act but admit it – doesn’t it feel oh, so satisfying?

We are, of course, talking about something that many people do when they think no one’s looking: Picking scabs off the skin. 

It’s one of the many no-nos that have been drummed into your head since you were a kid. “Germs will get into your skin”, “It’ll bleed”, “It’s painful” and the clincher (often said threateningly by Mum), “You want to get a scar is it?”

READ: Why you should stop that dirty habit of biting your nails when stressed or bored

Despite those warnings, a lot of us get that, erm, itch to get underneath the brown, crusty covering.

But where do we get that urge to pick?

Blame it on our ape ancestors and their penchant for grooming, said Luis Villazon, a zoologist, on the Science Focus website.

“It is probably a manifestation of our natural self-grooming behaviour. Our ape relatives constantly examine themselves and each other for ticks, dirt and small wounds, and any deviation from the normal contour of the body invites deeper scrutiny,” he said.

“The mild pain associated with picking a scab also releases endorphins, which can act as a reward,” he added.

READ: How frequent nose picking can enlarge nostrils and introduce more bacteria


Scabs form as your skin tries to regenerate new skin to heal the underlying wound, explained Dr Coni Liu, a dermatologist from DS Skin & Wellness Clinic. “If a scab is removed prematurely, it disrupts the healing process and often exposes the underlying wound before it is fully healed.”

What about scarring? Right off the bat, let’s get this old wives’ tale out of the way: The colour of the food you eat has no bearing on scarring, said Dr Liu. So no, dark soy sauce will not colour your wound or increase the risk of scars.

Man pouring out soy sauce
(Photo: Unsplash)

Rather, scarring depends on the depth of the wound, she continued. “If the original injury is at the deeper level of the dermis, it usually forms a scar, regardless of whether one picks the scab or not. However, picking at a scab can easily cause a deeper injury than the initial wound, and hence, lead to a higher risk of scarring.”

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The location of the wound matters, too, when it comes to the likelihood of scars. “Areas with good vascular supply – like the face, mucosal surfaces, palms and soles – generally heal faster and better. This is because our blood supply carries nutrients required for healing,” said Dr Liu. “Conversely, areas with poorer blood supply heal slower and poorer, for example, the shin area.”

Another good reason not to let your itchy fingers do the work: “It is not easy to judge if the scab is ready to be lifted off, and by picking at it or around it, we often inadvertently lift off more than we intend to,” said Dr Liu. “It is advised not to touch scabs or the surrounding area at all.”


Scabs often feel itchy because the healing process “secretes chemicals and creates mechanical stress that triggers the itch nerves”, explained Dr Liu. “To distract or soothe the urge to scratch, one can try patting or gently pinching the normal skin around the scab instead of making contact with the scab itself.”

If catching sight of something on your skin compels you to get it off (our ape instincts at play again), wear clothes that cover the scab, suggested Dr Liu. “Divert your attention and urge to scratch by using a stress ball or something to hold in your hands.”

To help your skin heal faster, it actually helps to keep the area moist, according to Dr Liu. “Cells need moisture to grow, divide and migrate at an increased rate to enhance the formation of new tissue.” 

Once the wound heals and a scab is formed, keep it moisturised with petroleum jelly, she recommended. It can also prevent itching and tingling.

Source: CNA/bk