According to various studies, the real answer is (drum roll please) yes. Sun exposure is a clear trigger for rosacea flareups and can make rosacea worse in the near and long-term for most people who experience this skin disorder. Sun exposure is the top trigger for rosacea symptoms in more than 80% of people who have rosacea, according to a survey conducted by the National Rosacea Society.

The degree the sun aggravates rosacea depends on the phenotype of rosacea, how long the skin is exposed to the sun’s rays, and the individual that is being exposed. Research clearly indicates that ultraviolet exposure is damaging to the skin. But why, specifically, does sun exposure trigger rosacea flareups or make it worse?

One reason is thought to be clients with rosacea have elevated levels of the antimicrobial peptide cathelicidin in the skin. The synthesis of vitamin D caused by UVB exposure induces expression of cathelicidins in keratinocytes. A complex biological cascade is set off and results in excessive production of the LL-37 peptide, which is suspected to be a contributing cause in all phenotypes of rosacea.

A second reason is thought to be UVB rays may heat up the skin and cause redness and flushing (blood flow to the skin). These flareups create vascular pathways that, when repeated many times, cause the tips of the blood vessels (known as capillaries) to remain permanently expanded, leading to fine, red lines called telangiectasia on the surface of the skin.

How can the aesthetician help guide clients with rosacea regarding sun exposure? Sound advice: The consensus is to apply the right sunscreen daily.

Physical sunscreens are the way to go for clients that have rosacea. Ingredients that are considered physical sunscreens are titanium dioxide or zinc oxide. Recommend a sunscreen with at least an SPF of 15, with broad-spectrum ultraviolet protection. As a side note, zinc oxide is antimicrobial and anti-inflammatory – an added benefit for rosacea sufferers.

Advise clients with rosacea to stay away from chemical sunscreens. Many chemical sunscreen ingredients can be irritating to rosacea or cause heat and flushing when they chemically alter ultraviolet light into warming energy. Do not suggest sunscreens that contain octinoxate, also known as octyl methoxycinnamate or ethylhexyl methoxycinnamate; avobenzone, also known as butyl methoxydibenzoylmethane, with a registered trade name of Parsol 1789; benzophenones; and any other chemical sunscreens for that matter.

Additional guidance: advise clients to seek shade or try and stay out of the sun between 10 A.M. to 2 P.M., when the sun is the strongest, and wear protective clothing like long-sleeved shirts, pants, wide-brimmed hats (three inches or more), and ultraviolet-protective sunglasses.

In conclusion, for most, sun exposure does contribute to rosacea flareups and worsening. Clients can and should curtail this by following proper sun exposure safety guidance.