One thing for sure Vitamin D seems to play a role and be a common thread in aggravating people stricken with the rosacea skin condition. "Eighty-one percent of patients with rosacea report that sun exposure makes it worse. Of the many environmental triggers that exacerbate the condition, sun exposure is actually the most common. This may be because patients with rosacea have elevated levels of the antimicrobial peptide, cathelicidin, in the affected skin. Vitamin D increases cathelicidin, which may explain why sun exposure is a common environmental trigger, though researchers don’t know for sure." claims
"Overgrowth of a dysfunctional intestinal flora or abnormal intestinal microbiome may play a role in causing the disease. Recently a trial of rifaximin, a non-absorbable antibiotic that treats intestinal overgrowth but does not leave the digestive tract, showed a 96% response rate; meaning, that almost all of the participant’s reported an improvement with this treatment."
So, what do you do? My advice is to apply at least SPF 30 full spectrum sunscreen in conjunction to wearing a hat for maximum protection. I prefer a physical versus a chemical sunscreen, because less people tend to have allergic reactions. Also, stay out of the sun from 10am to 3pm when sun exposure is at it's strongest. Last but not least, wash your face directly after exposure to get excess sebum off of the skin.
References:
http://www.rosacea-ltd.com/rosacea-and-sun-allergy/
https://www.vitamindcouncil.org/blog/sunlight-and-vitamin-d-do-they-trigger-rosacea/#
http://rosacea.org/tags/sun
Makeup by Lori Riley
Photo courtesy of Beiron Andersson