Acne (Acne Vulgaris) is a skin condition that arises from the combined action of four factors — excess sebum, follicular hyperkeratosis, C. acnes proliferation, and inflammation. The SKINROUTE SKIN100 analysis helps you identify your personal primary cause.
Adult acne is on the rise especially among women in their 20s–40s, and both its causes and approach differ from teenage acne.
The 4 core mechanisms behind acne
1. Excess sebum production
When sebaceous glands secrete too much sebum, it begins to build up around the pores. Sebum production is strongly influenced by androgens (male hormones), and stress, sleep deprivation, and high-GI foods make it worse.
2. Follicular hyperkeratosis
When keratinocytes at the follicle opening proliferate faster than normal and fail to shed properly, dead keratin tangles with sebum and clogs the pore. This is the start of blackheads and whiteheads.
3. C. acnes proliferation
The anaerobic environment inside a clogged pore is ideal for Cutibacterium acnes (formerly P. acnes) to multiply. As these bacteria break sebum down into fatty acids, they trigger an inflammatory response.
4. Inflammatory response
When immune cells react to the bacteria and release inflammatory cytokines, red, painful papules and pustules form. In severe cases this progresses to nodules and cysts, which can leave scars.
Characteristics by acne type
| Type | Appearance | Inflammation | Scarring risk |
|------|------------|--------------|---------------|
| Comedo (blackhead) | Open clogged pore | None | Low |
| Comedo (whitehead) | Closed clogged pore | None | Low |
| Papule | Small, red, firm bump | Yes | Moderate |
| Pustule | Lesion containing pus | Yes | Moderate |
| Nodule | Deep, hard, 5mm+ | Severe | High |
| Cyst | Most severe form | Severe | Very high |
Teenage vs adult acne
| Item | Teen acne | Adult acne |
|------|-----------|-----------|
| Main cause | Androgen surge | Hormones, stress, cosmetics |
| Common location | T-zone (forehead, nose) | Jawline, cheeks, neck |
| Age | 10s–20s | 20s–40s |
| Pattern | Widespread | Recurrent cycles, deep papules |
Everyday care practices
Cleansing: Twice a day, with lukewarm water and a mild acidic (pH 4.5–5.5) cleanser. Over-cleansing actually triggers more sebum.
Moisturizing: Acne-prone skin still needs moisture. Choose oil-free, non-comedogenic products. When hydration is lacking, skin produces even more sebum.
Exfoliation: A BHA (salicylic acid) treatment 1–2 times a week helps prevent clogged pores. Physical scrubs can worsen inflammation, so chemical exfoliation is recommended.
Diet: Studies suggest high-GI foods (white rice, sugar, refined carbs) and dairy can worsen acne. It doesn't apply to everyone, so keeping a food diary to identify your personal triggers helps.
Sleep and stress: Elevated cortisol increases sebum. Regular sleep and stress management are the foundation of acne care.
Preventing scars is the key
The most important thing in acne care is responding appropriately before scars form. Severe inflammatory acne, nodules, and cysts should always be seen by a dermatologist. Squeezing them yourself can push inflammation deeper and cause scarring and pigmentation.
Over-the-counter benzoyl peroxide (2.5–5%), salicylic acid (0.5–2%), and retinol-family ingredients have evidence-based benefits for acne care. Prescription medications (retinoids, antibiotics, isotretinoin, etc.) should only be used under professional guidance.
FAQ
Q: Why does acne suddenly flare up?
Hormonal changes (around menstruation, pregnancy, switching birth control), increased stress, new cosmetics, and lack of sleep are common causes. If sudden flares keep recurring, review both lifestyle changes and the products you're using.
Q: Can I squeeze acne with my hands?
Extraction of inflammatory acne (papules, pustules) should be done at a dermatology clinic with proper tools. Squeezing by hand pushes bacteria deeper and raises the risk of scars and pigmentation.
Q: Why does adult acne concentrate along the jawline?
Adult acne develops where hormone-sensitive sebaceous glands are well developed — the jawline, cheeks, and neck. It often syncs with the menstrual cycle, which is why it's also called hormonal acne.
Finding your acne cause with SKINROUTE
SKINROUTE SKIN100 measures 8 indicators including sebum, hydration, sensitivity, and barrier to identify your acne's main cause. Based on the results, your AI coach offers tailored guidance on cleansing, moisturizers, ingredients, and even diet.