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

What happens in the skin with rosacea?

Rosacea is more than just redness — it is a chronic inflammatory condition involving three interconnected problems: a weakened skin barrier, an overactive immune system, and disrupted blood vessel regulation. Research published in Frontiers in Immunology (2025) shows that rosacea-prone skin systematically lacks the proteins — claudins — that normally keep skin cells tightly packed together. As a result, the skin loses moisture and lets irritants, bacteria, and UV radiation in.

At the same time, the immune system’s TLR2/LL-37 pathway is chronically overactive. This means that even mild triggers — a glass of wine, a little sun, a cold wind — can set off a strong inflammatory response. Blood vessels dilate, and the skin becomes red and burns. Over time, permanent, visible blood vessels — telangiectasia — 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 produced measurable improvement in erythema — that is, clinically measured skin redness — in 94.7% of participants after eight weeks. The average redness score fell from 0.86 to 0.54. The mechanism is well established: zinc oxide inhibits the inflammatory pathways that drive rosacea’s chronic redness and keeps the immune system’s overreaction in check.

Second, zinc oxide forms a physical barrier on the skin’s surface. It protects against UV radiation — one of the most common rosacea triggers — environmental irritation, and microscopic particles that can destabilize an already vulnerable skin barrier. Zinc oxide is therefore not just symptom management: 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 — supporting the anti-inflammatory mechanism of zinc demonstrated in basic research.

Calm for unsettled skin — in the evening

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

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Sulfur — the underappreciated ingredient for rosacea inflammation

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

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. Next, sulfur has an antimicrobial effect: it inhibits the growth of bacteria and fungi that can complicate rosacea, including the Malassezia fungus associated with seborrheic dermatitis overlap.

The third mechanism is particularly relevant: sulfur has been shown to reduce Demodex mites on the skin. A 2024 study (PubMed PMID: 39042262) found Demodex mites in 80 % of rosacea patients — compared with just 20 % of 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 overall severity scores — and in head-to-head studies, combination formulations with sulfur outperformed metronidazole 0.75 % gel on erythema scores (p = 0,017).

How CØLM fits into a rosacea routine

CØLM Redness Relieving Cream is an evening treatment — not a morning cream. Use it 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, which can reduce its effectiveness.

A typical rosacea routine looks like this: In the morning, cleanse gently 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. Leave the cream on overnight and wash it off in the morning. You don’t need to add other active ingredients in the evening — CØLM is designed to work on its own. Always introduce one new product at a time, and wait 1–2 weeks before adding anything new. Expect to use it for 4–8 weeks before seeing the full results.

Ingredients to look for — and ingredients to avoid

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

Ingredients to avoid: alcohol (denat.), strong fragrances and essential oils, physical scrubs, high concentrations of retinol, 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 attention?

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

Ready to calm your skin?

CØLM Redness Relieving Cream — zinc oxide and sulfur for unsettled rosacea-prone skin. FOR EVENING USE ONLY. 449 kr / 30 ml.

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