The Science Behind Calm for Rosacea — What Zinc Oxide and Sulfur Actually Do

What happens in the skin with rosacea?

Rosacea is not just redness — it is a chronic inflammatory condition with three interconnected problems: a weakened skin defense, an overactive immune system, and disturbed blood vessel regulation. Research published in Frontiers in Immunology (2025) shows that rosacea skin systematically lacks the proteins — claudins — that normally keep skin cells tightly packed. The result is skin that loses moisture and allows irritants, bacteria, and UV radiation to penetrate.

At the same time, the immune system’s TLR2/LL-37 pathway is chronically overactivated. This means that even mild stimuli — a glass of wine, some sun, a cold wind — can trigger a strong inflammatory reaction. Blood vessels dilate, the skin reddens and burns. Over time, permanent visible blood vessels — telangiectasias — can develop as a direct result of repeated vascular overreaction.

Zinc oxide — the anti-inflammatory shield against rosacea redness

Zinc oxide is one of the best-documented active ingredients in topical skincare products for rosacea. It works in two ways.

First, it directly reduces inflammation. A study published in the Journal of Clinical and Aesthetic Dermatology (JCAD, 2025) found that a zinc oxide-based skincare formulation provided 94.7% of participants with measurable improvement in erythema — that is, skin-measured redness — after eight weeks. The average redness score dropped from 0.86 to 0.54. The mechanism is well known: zinc oxide inhibits the inflammatory pathways that drive rosacea’s chronic redness and keeps the immune system’s overreaction in check.

Secondly, zinc oxide forms a physical barrier on the skin’s surface. It protects against UV radiation — one of the most common rosacea triggers — against environmental irritation and against microscopic particles that can destabilize an already vulnerable skin barrier. Zinc oxide is therefore not just symptomatic treatment: it addresses one of rosacea’s fundamental problems, namely the barrier’s inability to keep irritants out. An older but still widely cited double-blind placebo-controlled study (Sharquie et al., PubMed) also showed that oral zinc sulfate significantly reduced rosacea severity — thereby supporting zinc’s anti-inflammatory mechanism from basic research.

Calm for troubled skin — in the evening

CØLM Redness Relieving Cream is formulated with zinc oxide and sulfur — two of the most well-documented ingredients against rosacea redness. Use only in the evening.

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Sulfur — the underestimated agent against rosacea inflammation

Sulfur has a long documented history in dermatology, and recent research confirms that it works against rosacea through three mechanisms simultaneously.

First and foremost, sulfur is keratolytic — it softens and helps remove dead skin cells from the skin’s surface. This keeps pores clear and reduces the clogging that can exacerbate inflammation. Furthermore, sulfur has an antimicrobial effect: it inhibits the growth of bacteria and fungi that can complicate rosacea, including the Malassezia yeast associated with seborrheic dermatitis overlap.

The third mechanism is particularly relevant: sulfur has been shown to reduce Demodex mites in the skin. A 2024 study (PubMed PMID: 39042262) found Demodex mites in 80% of rosacea patients — compared to only 20% in the control group. Sulfur’s effect against these mites thus helps reduce one of the underlying drivers of rosacea inflammation. A Japanese real-world study (PMC, 2023) documented that sulfur formulations significantly reduced erythema, papulopustules, and the overall severity score — and in head-to-head studies, combination formulations with sulfur outperformed 0.75% metronidazole gel on erythema score (p = 0.017).

How CØLM fits into a rosacea routine

CØLM Redness Relieving Cream is an evening treatment — not a morning cream. It is used after cleansing as the final step in your evening routine. This gives zinc oxide and sulfur optimal conditions to work while the skin regenerates overnight, and avoids friction with SPF and makeup that can reduce effectiveness.

A typical rosacea routine looks like this: In the morning, gently cleanse with a fragrance-free, pH-balanced facial cleanser and finish with SPF 50 protection — sun exposure is the most common rosacea trigger and should never be skipped. In the evening, cleanse again and finish with CØLM. The cream is left on overnight and washed off in the morning. You don’t need to add other active ingredients in the evening — CØLM is designed to work alone. Always introduce one new product at a time and wait 1–2 weeks before adding another. Expect to use it for 4–8 weeks before seeing full results.

Ingredients to look for — and ingredients to avoid

Ingredients proven beneficial for rosacea-prone skin include zinc oxide (anti-inflammatory and UV-protective), sulfur (antimicrobial and against Demodex), niacinamide (strengthens the skin barrier and reduces redness), hyaluronic acid (attracts moisture and keeps skin soft), and ceramides (rebuild the skin barrier by replacing the lipids rosacea skin lacks). Your cleanser should be based on betaine or amino acids — they cleanse effectively without disturbing the skin’s natural pH balance. Always look for products labeled “fragrance-free” and “for sensitive skin.” You can read more about skin barrier repair here.

Ingredients to avoid: alcohol (denat.), strong perfumes and essential oils, physical scrubs, retinol in high concentrations, and steroid creams without medical guidance. Also avoid introducing many active ingredients at once — start simple and build up gradually.

When should you seek medical help?

A consistent home routine helps most people with rosacea — but there are situations where you should contact a doctor or dermatologist. Seek professional evaluation if your symptoms worsen significantly despite changes in routine, if you experience red, irritated, or light-sensitive eyes (ocular rosacea requires ophthalmologic assessment), if the skin on your nose begins to thicken (rhinophyma), or if you do not see clear improvement after 6–8 weeks of consistent care. A dermatologist can prescribe prescription metronidazole gel, ivermectin cream, or azelaic acid — and in more severe cases, a short course of oral antibiotics (doxycycline) can significantly reduce inflammation.

Ready for calm skin?

CØLM Redness Relieving Cream — zinc oxide and sulfur for troubled rosacea skin. FOR evening use only. 449 kr / 30 ml.

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