The Science Behind Breakouts: Why You Get Them And How To Treat Them

Updated 06/14/22. As an esthetician with over 30 years of experience, I’ve seen almost every skin condition and concern out there. From sun damage and melasma to rosacea, wrinkles, and beyond. While none of them are necessarily easy to address, there’s one that can be particularly stubborn, and that’s acne.

Even though it might feel impossible, there are things you can do to help clear and prevent breakouts. To start, it’s helpful to know your specific skin type (breakouts will always be most prevalent for those with excess oil production who are prone to clogged pores, like Skin Types 1-4). It’s also helpful to know the type of breakouts you’re dealing with as well as the science behind them (did you know that the formation of a blemish can begin weeks—even months—before it appears?).

In this post, I’ll explain the life cycle of a blemish from start to finish. I’ll also share expert advice on how to get rid of breakouts, fast. Keep reading for all of this and more.

How Do Blemishes Happen?

Blemishes form in hair follicles, which are also called pores. These are ducts in the skin that are attached to sebaceous glands that produce sebum (oil). Hair grows from the bottom of the follicle to the top, and it’s through the follicle that sebum finds its way to the skin’s surface to keep it moisturized.

There are two main components of hair follicles to know about. The first component is the process of cellular turnover. This is when dead skin cells are shed to make way for new ones. Dead skin, when not shed properly, can end up blocking the follicle. The second component is bacteria. All hair follicles contain bacteria (however, not all bacteria are “bad,” meaning not all bacteria cause breakouts). If the pore is blocked by dead skin or debris, oxygen isn’t able to penetrate and breakout-causing bacteria can thrive. This is because breakout-causing bacteria can’t multiply in the presence of oxygen. 

Most blemishes form from pre-existing whiteheads and blackheads (blocked, hardened sebum deep within pores). They become inflamed from the dead skin cells that block the pore opening, which allow “bad” bacteria to thrive. This is why I always recommend regular deep-pore cleansing facials for breakout-prone skin types. They minimize pore blockages.

In Normal Skin Types:

• Oil flows smoothly through the follicle
• Dead skin cells are consistently shed
• Oxygen can penetrate the pore to keep bacteria at bay
• The skin looks clear, balanced, and blemish-free

In Blemish-Prone Skin Types:

• Overactive sebaceous glands produce an excess of oil
• This oil is thick and sticky, so it clumps together and doesn’t flow easily through the follicle
• There is an abnormal shedding of dead skin cells causing a build-up inside the follicle
• Dead skin cells mix with oil, blocking oxygen from entering the follicle
• C. acnes (formerly called P. acnes) bacteria trigger an infection, forming a visible breakout

The perfect formula for a blemish is oil + dead skin cells + a lack of oxygen. Proper skincare products can help disrupt this process, leading to clearer-looking skin.

The Life Cycle of a Blemish

Did you know blemishes have life cycles? It’s true! Once an infection has started, bacteria increase and irritate the follicle along with the sebaceous gland. This causes a rupture that triggers redness, inflammation, and swelling in the reticular layer of the skin. The reticular layer is located in the dermis, which is the layer of skin where blood vessels and immune cells are located.

When your body recognizes there is an infection, its immune system kicks in to start the healing process. White blood cells (immune cells) rush to the follicle to destroy bacteria. At this stage, the blemish is called a papule—a red, painful bump with no visible whitehead on the surface (this is the stage right before it becomes a full-blown breakout).

Next, white blood cells die off and accumulate, along with other fluid and debris. This forms a pustule, which is when there’s a visible whitehead as a result of white blood cells. (It’s important to note that not all breakouts will transition fully into this stage).

A cyst, on the other hand, is larger than a pustule. It’s considered to be a severe inflammatory breakout, and as a result, can be quite painful. Cysts are typically triggered by a surge of hormones. For some unknown reason, the skin’s sebaceous glands become hypersensitive to this hormone cascade and react by overproducing sebum. So much so, that the sebaceous gland becomes swollen and hardened. Unable to push the extra oil into the lining of the hair follicle, the gland bursts underneath the skin. This causes inflammation and irritation.

To get rid of a blemish as fast as possible, it’s important to treat each stage appropriately. Learn more about the life cycle of a blemish and how to treat a breakout at every stage.

The Bottom Line

Breakouts can be difficult to deal with but knowing a little bit more about them and how they happen can be helpful in minimizing them. While there is no single reason why some people struggle with breakouts and others don’t, it likely comes down to genetics. It’s not all bad, though. As I’ve always told my clients, people who struggle with breakouts are actually lucky (yes, really! Learn why).

Next, read this complete guide to clearing clogged pores, once and for all.

Renée Rouleau

Celebrity Esthetician & Skincare Expert
As an esthetician trained in cosmetic chemistry, Renée Rouleau has spent 30 years researching skin, educating her audience, and building an award-winning line of products. Her hands-on experience as an esthetician and trusted skin care expert has created a real-world solution — products that are formulated for nine different types of skin so your face will get exactly what it needs to look and feel its best. Trusted by celebrities, editors, bloggers, and skincare obsessives around the globe, her vast real-world knowledge and constant research are why Marie Claire calls her “the most passionate skin practitioner we know.”