To treat acne at its root and achieve long-term results, identifying the correct causes is extremely important. When you clearly understand the specific causes, the treatment process becomes more precise and effective, while also helping prevent future breakouts. Let HBIO Clinic walk you through the top 10 most common causes of acne in the article below.
What Is Acne?
Acne is a common dermatological condition that appears on various areas of the body, including the face, back, chest, chin, neck, and shoulders. It often causes symptoms such as redness, pus-filled pimples, itching, and pain. The main causes of acne include hormonal changes and external environmental factors like bacteria and clogged hair follicles.

Common Types of Acne
Acne can be classified based on how it presents on the skin, with common types including: regular acne (acne vulgaris), red acne, under-the-skin acne, cystic acne (inflamed nodules), whiteheads, blackheads, pustules, and inflammatory acne.
Each type of acne has its own characteristics and underlying causes, requiring different treatment and skincare approaches to effectively prevent and reduce breakouts.
10 Most Common Causes of Acne
Acne can result from a variety of factors. Understanding these causes will help you treat and care for your skin more effectively.
1. Acne-Causing Bacteria: Propionibacterium Acnes (P. Acnes)
The most common cause of acne is bacterial infection, particularly by Propionibacterium acnes (P. Acnes) – an anaerobic bacterium that resides deep within hair follicles and pores.

Under normal conditions, this bacterium is harmless. However, when the pores are clogged with dirt and lack oxygen, P. Acnes multiplies rapidly, attacking the sebaceous glands and triggering inflammation and swelling, which leads to the formation of acne.
2. Hormonal Changes
Hormonal fluctuations are one of the most common causes of acne, especially during puberty, pregnancy, or when using birth control pills. Hormonal changes—particularly elevated androgen levels—stimulate the sebaceous glands to produce more oil.

This excess oil clogs pores and creates the perfect environment for acne to develop. Hormonal acne often appears on areas such as the chin, forehead, and cheeks.
3. Enlarged Pores
Large pores can lead to acne, particularly blackheads. Due to their size, they easily trap dirt, excess oil, and dead skin cells, yet are difficult to clean thoroughly with regular facial cleansers. This accumulation provides a favorable environment for bacteria to grow, clogging the pores and causing acne breakouts.

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4. Using Inappropriate Skincare or Cosmetic Products
If your acne persists and shows no signs of improvement, one possible reason may be that you’re using products that are unsuitable for your skin or lack clear origins.
Cosmetic products containing corticosteroids can thin the skin and weaken its natural barrier, making it more prone to irritation and severe breakouts.
5. Accumulation of Dead Skin Cells
Failing to exfoliate regularly causes dead skin cells to build up, clogging pores and hindering nutrient absorption. This also disrupts moisture balance, weakens the skin’s barrier, and provides an ideal environment for acne-causing bacteria to thrive.
6. Side Effects of Medications
Certain medications can cause acne as a side effect, especially those containing corticosteroids, lithium, steroids, or birth control pills.
Improper medication use or abrupt discontinuation can also trigger skin reactions and worsen acne.
7. Overactive Sebaceous Glands and Excess Oil
In many individuals, overactive sebaceous glands—either due to genetics or dehydrated skin—can cause clogged pores. Without proper care, this condition creates an ideal environment for acne to develop.

8. Genetics
Genetics is another common factor in acne development. If acne-prone skin runs in your family, your chances of experiencing breakouts may be higher.
9. Prolonged Stress and Anxiety
Chronic stress can trigger the body to produce cortisol, which increases oil production and clogs pores. This creates the perfect condition for bacterial growth and acne flare-ups.
10. Unhealthy Lifestyle Habits
Unhealthy habits such as staying up late, poor diet, and lack of physical activity can disrupt hormonal balance and impair the body’s detox function. As a result, toxins and oil accumulate on the skin, leading to persistent and difficult-to-control acne.
Understanding the causes of acne is a crucial first step in effective skincare and treatment. If you’re struggling with acne and need a personalized treatment plan, HBIO Clinic – Facial Skincare & Spa is the perfect choice. With a team of experienced professionals, cutting-edge technology, and customized solutions, HBIO Clinic is committed to providing safe and effective skincare treatments that help you regain clear, smooth, and youthful skin. Contact us today for expert consultation and experience the best in skincare.
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Hbio Clinic - Facial Skincare & Spa
Phone: 0947 697 795
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