Rajani Katta, MD, a clinical professor of dermatology at the McGovern Medical School at UTHealth in Houston, TX, and the author of a book for the general public on diet and dermatology.
Even though rosacea affects more than 16 million Americans, the disease is still not well understood, including potential triggers.1 Diet is one factor that patients with rosacea frequently report as contributing to flares, and as the emphasis on food-based disease management gains popularity in the broader health care world, what we know about how different diets and alcohol affect this particular disease continues to evolve.
Rajani Katta, MD, a dermatologist practicing in Bellaire, TX, specializes in the study of the relationship between diet and skin. Dr Katta is also clinical professor of dermatology at the McGovern Medical School at UTHealth in Houston, TX, and the author of Glow: The Dermatologist’s Guide to a Whole Foods Younger Skin Diet. The Dermatologist spoke to her about what is known about the role food can play in rosacea, including possible triggers and ways to use diet to manage the condition.
Q. How much data is there to support the link between rosacea flares and diet?
A. We’ve known for a long time, just anecdotally by speaking to patients, that there are certain foods or beverages that seem to cause flares of their rosacea. Surprisingly, there is very little published research in this area. One of the only things we have to go on is a 2018 survey that was sent out by the National Rosacea Society (NRS).2 Of more than 516 patients with rosacea who responded, the vast majority, 73%, reported having altered their diet to see if it would help their condition. Of those who tried it, 74% reported that changing their eating habits was an effective way to reduce the number of rosacea flares they experienced.
Q. Can you discuss the different types of dietary triggers reported in that survey?
A. Again, this is not formal research like a prospective trial, but based on those and previous survey results,2,3 you can categorize the food and beverages patients reported into four different groups. The first group includes hot beverages, especially hot coffee and hot tea. Alcohol was another frequent trigger, one that we have known about for a long time. Then there were foods that contain capsaicin, a natural chemical that’s found in different spices and hot peppers, and foods that contain cinnamaldehyde, a compound found in cinnamon, tomatoes, citrus, and chocolate.
Q. What can be concluded about the mechanism of action behind these triggers?
A. All four of these food groups can be considered vasodilators, meaning they cause blood vessels to dilate. Hot beverages raise core body temperature, which causes vessels to dilate, and alcohol has a similar effect. We know through laboratory and animal studies that cinnamaldehyde and capsaicin act to activate transient receptor potential (TRP) channels, and that can cause vasodilatation as well. That dilation of blood vessels in rosacea patients seems to act to increase inflammation of the skin.
Q. Should dermatologists advise their patients to avoid these foods?
A. There are two different approaches that you can take when you’re working with patients. The first is to give them a list of potential triggers and say, “These are triggers that have been a problem for other patients. You might just want to keep a food diary and pay attention to your own triggers over the next 2 months.” Some patients might find that alcohol is a big one for them. Other patients might find that tomato is a big one for them. That’s option one. Educate the patient, and then request that they keep a food diary.
Option number two is if the patient is really concerned about the food-skin link, then you could just tell them to avoid all these foods for a period of 8 weeks. Then they can slowly add them back in one by one to see if they can identify individual triggers.
Q. On the whole, are some of these food triggers more common than others?
A. One of the more common triggers I hear anecdotally, just from talking to patients, is spicy food. Alcohol also tends to be one of the more common triggers. For patients who responded to the earlier NRS survey, 52% reported that wine was a trigger for them, and 40% reported that hard liquor was. Also, 30% of survey respondents described tomatoes as a frequent trigger, and 23% said chocolate was.