Acne & Sun: the deceptive duo that sets the stage for skin breakouts in the fall
Who hasn't enjoyed seeing their skin suddenly become smoother when looking in the mirror on vacation? Under the action of UV rays, pimples seem to fade and the complexion becomes more even. But this improvement is only temporary: in the fall, lesions often return with a vengeance. What mechanisms explain this deceptive cycle? How can you enjoy the sun sensibly without triggering a rebound effect, hyperpigmentation, or aggravating existing acne?
1. The summer illusion: why skin appears clearer
Heat accentuates dehydration; the sebaceous glands temporarily slow down their sebum production. At the same time, the epidermis thickens and becomes more pigmented as a defense mechanism, camouflaging redness and imperfections. This visual improvement lasts only a few weeks: the skin's regulatory mechanisms quickly kick in to compensate for the loss of water and lipids.
2. Anatomy of the rebound effect
When dehydration persists, the sebaceous glands react by producing excess sebum: sebum accumulates under a thickened stratum corneum, clogs the follicles, and creates an environment conducive to bacterial proliferation. As soon as the epidermis returns to its normal thickness, microcysts, closed comedones, and inflammatory lesions reappear suddenly.
3. Hyperpigmentation: double punishment for scars
Post-inflammatory scars already secrete excess melanin. Under UV light, this production intensifies: the marques brown and persist. The higher the phototype, the more visible and lasting these spots are. Direct exposure without protection should therefore be avoided during the healing phase.
4. Photosensitization: the silent danger of treatments
Many acne treatments (topical or oral retinoids, benzoyl peroxide, certain antibiotic therapies) make the skin hypersensitive to light. Redness, burning, and peeling may occur after moderate exposure. In summer, it is recommended to suspend any treatment that is not essential. If this is not possible, apply the treatment in the evening, use SPF 50+ sunscreen the next day, and limit sun exposure to the least intense hours of the day.
5. Sun protection suitable for acne-prone skin
To preserve skin benefits without clogging pores:
- Wide spectrum : filter both UVA and UVB rays, which cause sunburn, premature aging, and cancer risk.
- High protection rating : SPF 50+ for fair skin types, at least SPF 30 for medium to dark skin.
- Non-comedogenic formula, non-greasy finish : choose oil-free emulsions, fluids, or mattifying gels to limit unwanted shine and the feeling of occlusion.
- Regular renewal : every two hours and systematically after swimming or intense perspiration.
6. Daily routine to counteract the sun
- Clean morning and evening with a gentle cleanser to remove sweat, sunscreen, and pollutants.
- Moisturize with a light, non-greasy treatment to restore the skin barrier.
- Exfoliate once a week using an enzyme scrub or a mild acid to limit keratinization.
- Drink 1.5 to 2 liters of water per day to maintain microcirculation and skin suppleness.
- Choose the right time slot : prioritize exposure before 11 a.m. and after 4 p.m., wearing protective clothing (hat, sunglasses).
