Acne is a skin condition that occurs when your hair follicles become plugged with oil and dead skin cells.
It causes whiteheads, blackheads or pimples. Acne is most common among teenagers, though it affects people of all ages. Effective acne treatments are available, but acne can be persistent. The pimples and bumps heal slowly, and when one begins to go away, others seem to crop up. Depending on its severity, acne can cause emotional distress and scar the skin. The earlier you start treatment, the lower your risk of such problems.
Four main factors cause acne:
- Excess oil (sebum) production
- Hair follicles clogged by oil and dead skin cells
- Bacteria
- Inflammation
Acne typically appears on your face, forehead, chest, upper back and shoulders because these areas of skin have the most oil (sebaceous) glands. Hair follicles are connected to oil glands.
The follicle wall may bulge and produce a whitehead. Or the plug may be open to the surface and darken, causing a blackhead. A blackhead may look like dirt stuck in pores. But actually the pore is congested with bacteria and oil, which turns brown when it's exposed to the air.
Pimples are raised red spots with a white center that develop when blocked hair follicles become inflamed or infected with bacteria. Blockages and inflammation deep inside hair follicles produce cystlike lumps beneath the surface of your skin. Other pores in your skin, which are the openings of the sweat glands, aren't usually involved in acne.
Certain things may trigger or worsen acne:
- Hormonal changes. Androgens are hormones that increase in boys and girls during puberty and cause the sebaceous glands to enlarge and make more sebum. Hormone changes during midlife, particularly in women, can lead to breakouts too.
- Certain medications. Examples include drugs containing corticosteroids, testosterone or lithium.
- Diet. Studies indicate that consuming certain foods — including carbohydrate-rich foods, such as bread, bagels and chips — may worsen acne. Further study is needed to examine whether people with acne would benefit from following specific dietary restrictions.
- Stress. Stress doesn't cause acne, but if you have acne already, stress may make it worse.
Acne scars are marks left behind after the acne itself has gone away. It’s really common. About 1 in 5 people have acne scars on their face, chest, or back.
If your goal is to make your scars less noticeable, a dermatologist (skin doctor) can help. They can look at your skin and suggest a treatment that can help. Many at-home or in-office treatments can help clear up acne scars. A dermatologist can explain what's most likely to work for your skin.
Types of Acne Scars
Acne can leave seven different kinds of scars. It's common to have more than one type. If your skin is prone to breaking out, you might notice:
- Ice pick acne scars. This type of scar looks like an ice pick was used to make it. It has a wide hole at the top that gets smaller as it gets deeper. You're more likely to get ice pick scars on your forehead or upper cheeks because the skin there is naturally thinner.
- Boxcar acne scars. These may look like a square or circle was pressed into your skin. Often, boxcar scars show up on your jawline or lower cheeks.
- Rolling acne scars. If your skin looks wavy and uneven, you have what's called a rolling scar. It's caused by damage under your skin's surface. This type of scarring is often seen on the lower half of your cheeks or the skin around your jaw.
- Hypertrophic acne scars. Some scars indent your skin. Other types, such as hypertrophic scars, create a flat or raised scar tissue over where your acne was. It happens when too much collagen in your skin grows over the area. You might see this type of acne scar on your chest, back, shoulders, or face.
- Keloid acne scars. These raised bumps may be darker than your skin. They may also be bigger than the patch of acne that you once had. Like hypertrophic scars, keloid scars can sometimes be itchy or painful.
- Dark spots or staining and acne scars. You might see a dark spot appear once a pimple clears, especially if you have medium to dark skin. That's because acne can accidentally trigger more melanin (pigment) in your skin.
- Perifollicular elastolysis. These round or oval little bumps may match the color of your skin. Also called papular scars, they can appear on your arms, chest, back, or shoulders, as well as on your face.
During a consultation, a dermatologist will figure out the type of scars you have and how severe they are, based on this scale:
- A red, flat scar. This is the mildest type of scar.
- Mild acne scar. It can be easily covered up, for instance, with makeup or a mustache or beard.
- Moderate acne scar. This can be seen by others who are close by.
- Severe acne scar. It can't be covered up and can be seen from at least 50 centimeters away.
This information, as well as where the scars are on your body, will help your dermatologist figure out the next steps.