What causes acne?

An acne lesion (pimple) grows when bacteria, oils and dead skin fill up and inflame pores, the tiny openings in your skin through which oil and sweat rise to the surface. Some 40,000 cells fall off your skin every hour but, sometimes, those dead cells clog up a pore. Sometimes clogged pores are small and result in “whiteheads or blackheads.” Sometimes these pores become inflamed and lead to other types of acne.

If you have acne, you’re not alone! Acne is the most common skin condition in the world. About 80% of people between the ages of 11 and 30 will have it. Teenagers get acne thanks to their changing hormones. Adults have stress, the environment, menstrual cycles, oil-based products and birth control pills to blame, although hormones can still play a role.

What are the types of acne and what do they look like?

Acne presents as many different forms. Whiteheads and blackheads are typical and tend to heal smoothly more often than not. Then there are the types that can lead to scarring:

  • Papules: Pink to red bumps that hurt when you touch them.
  • Pustules: Pus-filled lesions. They’re red at the base and white or yellow at the top.
  • Nodules: Solid lesions. They’re larger than papules and pustules and can hurt more because they extend deeper into the skin.
  • Cysts: Cysts lie deep within the skin. They’re painful, full of pus and are most likely to scar.

How does acne cause scars?

Your skin is your largest organ. It has three main layers. They are, starting with the outermost, the epidermis, the dermis and the hypodermis. The layers protect your fragile insides from the elements, from UV rays and bacteria, and they also help produce vitamin D thanks to sunlight. Any area with sebaceous glands is prone to acne — especially the face, back and chest.

Acne scars are the result of inflammation of acne blemishes. The acne pore swells and a breakdown occurs in the wall of the pore. Some acne blemishes are small and the scars created are shallow and heal quickly. Sometimes the contents of blemishes spill into the surrounding tissue and cause deeper scars. The skin’s response is to repair the scar by forming new collagen fibers.

Acne scars take on two main forms: either a scar develops when there is a loss of tissue, resulting in an indentation in the surface of the skin; or, a scar develops that is raised on the surface of the skin. This type of acne scar, in fact, is a sign that your skin is doing its job — but, perhaps, too well. Your skin creates collagen (“repair tissue”) to help heal the wound — the acne — but, if it makes too much collagen, raised scars form.

Keep in mind that just because you have acne, that doesn’t mean you’ll get scars. And if you do (one in five people with acne will also have scarring), the good news is that not all acne scars are permanent! Treatments are available. Some treatments nearly remove the scars while others help the skin heal itself with its own collagen.

What are the types of acne scars and what do they look like?

If you have acne scarring, you’re likely to have more than one of the following types. Rarely does someone have just boxcar scars, or just keloid scars, etc. Each of these can be treated with varying degrees of success.

Atrophic or Depressed Scarring:

  • Ice pick: An ice pick tool has a wide shaft that narrows down to the tip. This type of acne scar resembles the tool in that it’s a hole that’s wide at the top and narrows to a point as it goes deeper into the skin. Such an indentation is common and also one of the most challenging scars to heal. You’ll find them on your forehead and upper cheeks, where your skin is thinner.
  • Rolling: These scars are typically found on the lower cheeks and jaw, where your skin is thicker. The indents have sloping edges that makes the skin look uneven and wavy.
  • Boxcar: Boxcar scars are indents that have sharper edges. Those edges go down deep into the skin. These scars are common on the lower checks and jaw.

Hypertrophic or keloid scars: These lesions of scar tissue rise off the skin. They’re caused when fibrous tissues, the collagen, in the region of the skin overgrow. These scars are usually found on the chest, back and shoulders and jaw line and can be itchy, tender or painful.

How common is acne scarring?

Very common. About 80% of people between the ages of 11 and 30 will have acne, and one out of five of that population will have scarring. Teenagers are the hardest hit. Nearly 90% of them will get acne.

What causes acne?

Clogged pores. Dead skin, oils and bacteria build up in your pores and inflame them. You might also have a genetic predisposition to acne.

What causes acne scars?

Scars happen because your body is trying to repair the acne. How your unique body responds to a wound determines if and how much scarring you’ll have. The process of repair includes the creation of collagen. If there’s too much collagen then the raised scars appear. Other scarring is caused by the loss of tissue, which creates pits or indentations in the skin.

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