Acne and acne scars — the whole picture
Acne is inflammation in the pore (the pilosebaceous unit); acne scars are the color or texture left behind as that inflammation heals. Because the causes differ, it helps to think of "the acne you have now" and "the scars left behind" separately.
Why it happens — the mechanism
Acne arises mainly from four overlapping factors:
- Excess sebum — influenced by male hormones (androgens).
- Abnormal keratinization at the pore opening — the pore clogs.
- Growth of acne bacteria (C. acnes) — multiplying inside the clogged pore.
- Inflammation — it becomes red, swollen, and pus-filled.
In adolescence sebum peaks, so it appears on the forehead and nose; in adults — especially men — it recurs along the jaw and jawline, where hormones, shaving, and dryness take effect.
Why scars remain
The deeper and longer the inflammation, the more likely a scar. Pigmentation from melanin (brown marks), redness from capillaries, and pits (craters) from a disrupted balance of collagen breakdown and repair. With the same acne, the more you squeeze, touch, or prolong it, the higher the scarring risk.
What makes it worse
- Physical irritation and dryness from shaving
- The habit of touching or squeezing
- Lack of sleep and stress (affecting sebum and turnover)
- An unsuitable cleanser, or barrier damage from over-washing
Common misconceptions
- "Washing cures it" — over-washing can break the barrier and worsen it.
- "Only greasy food causes it" — diet is one factor; hormones, keratinization, and bacteria are more fundamental.
- "Scars always fade with time" — pigmentation fades, but pits do not return on their own.
Japan vs. overseas — a difference in view
The standard for acne treatment is the same worldwide — topical retinoids, and oral medication for severe cases. What differs is access. In the West, tretinoin and oral isotretinoin have long been widely prescribed.
In Japan, adapalene was approved relatively late (2008) and isotretinoin remains unapproved (self-pay / personal import), so the entry point of "suppressing inflammation early through medicine" was narrower for a long time. As a result, men in Japan tend to self-treat with over-the-counter care and skincare for longer before seeing a clinic. Same mechanism, different point at which you meet medicine.
A map of options
Reviewing lifestyle and skincare / over-the-counter actives / insured dermatology (topical, oral) / out-of-pocket procedures (peels, lasers — especially for scars). The entry point changes depending on whether your concern is "the acne you have now" or "the scars left behind."