What Is Acne?
Acne is a common skin disorder, with 4.4 million new cases diagnosed every year in the U.S. (Bunick, 2025).
Most people think of pimples when they hear the word acne. While they are a common symptom, acne isn’t just a few blemishes. It’s a complicated inflammatory condition that can have a significant emotional toll on people who experience it.
Breakouts are the most obvious visual feature of acne. They can appear as non-inflamed whiteheads and blackheads, or inflamed pimples that fill with pus and swell up under the skin, causing pain.
Acne also causes oily skin and inflammation which appear as swelling, redness, or pain. This skin inflammation can happen without any visible breakouts present.
What Causes Acne?
Acne happens when the skin’s hair follicles become blocked with too much of the body’s natural oil (sebum) and skin cells. This creates the perfect environment for bacteria to grow and multiply, leading to inflammation and pain.
Although we don’t fully understand why this process happens, we do know that acne can happen when:
too much sebum is produced
skin cells turn over in an abnormal way
there’s an overgrowth of normal skin bacteria
the hair follicle and oil-producing cells inside are prone to inflammation
Certain factors can increase the risk of these things happening, including genetics, hormonal fluctuations and diet.
Genetics
Acne can run in families, and if your parents had acne it’s more likely you’ll also experience it. In fact, one study of twins found that genes were 81% responsible for the risk of developing acne (Bataille et al., 2002).
Hormones
Hormones are another key acne risk factor.
High levels of androgens like testosterone (or sensitivity to them) can increase sebum production and skin cell turnover in the hair follicle. This leads follicles to become plugged and bacteria to accumulate and breed. Increased androgen production is one of the main causes of acne in teenagers.
Women’s changing hormones throughout the menstrual cycle may partly explain why they’re more likely to experience acne than men. Leading up to a woman’s period, estrogen levels drop. As estrogen usually reduces androgen and sebum production, the sudden drop can trigger an acne flare-up.
Diet and insulin
A high glycemic index (GI) diet is the most well-researched dietary trigger for acne (Meixiong et al., 2022). This means foods that cause a large spike in blood sugar, like white bread, fruit, and foods with lots of added sugar.
But this connection is likely down to another hormone: insulin. The blood sugar spike caused by high GI foods also raises insulin levels, leading to increased sebum production.
There’s limited evidence that other foods, like dairy and meat products, may also trigger acne, but more research is needed. These foods may raise levels of a protein similar to insulin called insulin-like growth factor that also increases sebum production.
Your microbiome
As acne is caused by an imbalance of normal skin bacteria, your microbiome also contributes. Everyone’s microbiome (the microorganisms that live on and inside the body) is unique, but an overgrowth of harmful species is linked to acne (Lee et al., 2019).
Excessive growth of the bacteria species Cutibacterium acnes on the skin and even an imbalance of certain gut microbiomes can increase skin inflammation. This plays a role in developing acne.
Who Is at Risk?
Teenagers and older children aged 10-19 years old are the group most likely to experience acne, but acne also affects many adults. In adults, women are around twice as likely to have acne than men.
We’ve already discussed that having a family history of acne, eating a high glycemic index diet, your microbiome, and hormonal changes raise your acne risk, but some other factors can contribute.
Excessive sweating, stress, smoking, certain medications, and cosmetics/moisturizers that clog pores can all increase the chances of developing acne (Kutlu et al., 2022). Although some risk factors can’t be altered, many of the things we’ve listed can be avoided or dealt with.
Despite a common misconception, acne isn’t caused by not washing your face. In fact, washing your face too often (more than twice a day) can dry out the skin and disrupt the skin barrier which can actually make acne worse.
What Are the Symptoms of Acne?
Acne can present with oily skin, inflammation, and pimples.
There are several different types of blemishes and these can be divided into non-inflammatory (like blackheads and whiteheads) and inflammatory (including papules, pustules, nodules, and cysts).
You can experience several different types of pimples at the same time.
Blackheads are small, black pimples caused by blocked hair follicles. The dark color isn’t caused by dirt, but by a chemical reaction that happens to the sebum trapped there.
Whiteheads can look similar to blackheads but they appear as white or yellow. They’re also small, raised bumps without any redness/inflammation.
Inflamed blemishes tend to be red and painful. They can be:
small red bumps known as papules
small inflamed pus-filled pimples called pustules
larger inflamed bumps under the skin known as nodules
large pus-filled cysts that look similar to boils
Blackheads, whiteheads, and inflammatory acne are most commonly found on the face, but you may also notice them on your back and/or chest.
How Is Acne Diagnosed?
A physician can usually diagnose acne from looking at your skin and discussing your symptoms with you. There’s generally no need for extra tests or investigations unless they suspect an underlying medical condition could be causing your acne.
Your doctor will often want to examine the different areas where you’ve got acne to see which types of pimples are present and how severe it is. This will impact the type of treatments that you’ll need.
Acne is typically categorized as mild, moderate, or severe. Mild acne can often be treated with over-the-counter medication from a pharmacist, while more severe acne may need stronger treatments.
Our acne treatment page includes more information on the different acne treatment options and who they’re most suitable for.
How Is Acne Treated With Regenerative Therapy?
Regenerative therapy for acne focuses on stimulating the body’s natural healing processes to improve active acne and scarring. It uses different therapies formulated from the body’s own cells, proteins, and biomaterials.
Common types of regenerative therapy for acne include:
Platelet-rich plasma treatment (injection of concentrated blood that’s rich in platelets which support tissue repair) (Jafarzadeh et al., 2024)
Stem cell treatment (injection of stem cells —“master cells” that can divide into other cell types — to stimulate healing and reduce inflammation) (Shimizu et al., 2022)
Fibroblast cell treatment (injection of collagen-producing fibroblasts to reduce scarring) (Shimizu et al., 2022)
Cell-free therapies (using cell extracts to reduce inflammation and improve skin texture) (Shimizu et al., 2022)
Regenerative therapies can be used as an add-on to other acne treatments to manage inflammation, improve skin texture and reduce scarring (Jafarzadeh et al., 2024; Shimizu et al., 2022).
What Are the Possible Complications if Acne Goes Untreated?
Teenage acne may improve by itself as you get older and hormone levels stabilize, but leaving it untreated can lead to scarring. Adult acne is less likely to improve on its own.
If acne isn’t dealt with properly, it can cause indentations, irregular pigmentation and permanent scars in some cases. Severe or inflammatory acne is more likely to lead to scarring.
This scarring can be grouped into 3 main types:
Boxcar scars (circular indentations or craters)
Ice pick scars (small, deep holes)
Rolling scars (bands that form under the skin making the surface appear uneven)
Acne at any age can also have a significant impact on your self-esteem and body image, whether that’s active acne or the scars it leaves behind.
It’s a good idea to seek advice from your doctor for anything more than mild acne. This will ensure you minimize the chances of scarring and can address any factors that could be worsening your acne.
Can Acne Be Prevented?
No, acne can’t be completely avoided or cured because it’s caused by lots of interconnected factors you can’t change. But there are things you can do to reduce the chances of a flare-up and treat one if it does happen.
Try to wash your face and other affected areas with lukewarm water rather than very hot or cold water. Use a mild cleanser up to twice a day, but no more, as this can dry skin out and worsen sebum production.
Don’t forget to remove any makeup properly before bed if you wear it. Use a fragrance-free water-based moisturizer after cleansing if you get dry skin, but stay away from oil-based skincare products/makeup as they can block pores.
Aim to shower immediately after exercising or getting sweaty and wash your hair regularly. Avoid letting hair get on your face and try to avoid touching your face throughout the day too. It’s important not to pick or squeeze pimples as this can cause scarring.
Stay out of strong sunlight/tanning beds and apply sun protection before going outside.
Avoid eating a diet that’s high in refined carbohydrates or sugar as this can spike insulin and increase sebum production.
Finally, as stress can worsen acne, it’s a good idea to find healthy ways to manage it. This can be anything from regular exercise to journaling to meditation.
Getting treatment for acne early can help reduce the chances of acne-related skin damage and scarring.
Takeaway
Acne can be frustrating, painful and impact your self-esteem. It’s a complicated condition that’s impacted by your genes, hormones, what you eat, and even the microorganisms that live in your body.
Self care and lifestyle changes can often help with mild acne, but moderate to severe acne usually requires additional treatment. This can come in the form of traditional prescription acne treatments from a doctor but newer regenerative therapies that boost the body’s natural healing abilities may also play a role.
