Here's a medical news story that combines a common habit (drinking coffee) with a common skin condition (rosacea) — and it even has a happy ending.
What is rosacea?
Rosacea is probably something you've seen plenty of times and didn't know what it was — or perhaps you have it yourself. It's that pink or red discoloration on the cheeks some people have, especially fair-haired women. Sometimes there are small bumps that may look a bit like acne. If you look closely (after asking nicely for permission, of course), you'll see tiny blood vessels just under the surface of the skin. In more severe cases it may involve the chin, forehead, nose, ears, and other skin surfaces. It may affect the eyes, eyelids, and cause thickening of the skin over the nose.
We don't know what causes rosacea. However, there are theories that it may be, at least in part, a genetic condition, as it can run in families. Because the immune system seems to be involved in the inflammation of rosacea, and because other autoimmune conditions (such as type 1 diabetes and multiple sclerosis) may accompany rosacea, abnormal immune function may play a role. Medications (such as topical anti-inflammatory drugs) and antibiotics can reduce redness and inflammation but there is no cure. Many people seem to be able to reduce signs of rosacea by modifying their diet to avoid foods that trigger it.
Rosacea affects more than 14 million people in the U.S., including some celebrities, such as Bill Clinton. And while it's not dangerous, it can have a significant cosmetic impact. Caffeine, sun exposure, spicy foods, and hormonal factors are thought to be able to trigger rosacea's development or make it worse once present. Yet, a new study challenges the connection between caffeine and rosacea.
More coffee, less rosacea?
A recent study analyzed health data from surveys provided to nearly 83,000 women over more than a decade and found that:
—Those drinking four or more cups of coffee per day were significantly less likely to report a diagnosis of rosacea than those who drank little or no coffee.
—Those drinking less than four cups of coffee each day were also less likely to have rosacea, though the protective effect was smaller.
—Consumption of decaffeinated coffee was not linked to a lower incidence of rosacea.
—Caffeine intake from other foods or beverages (such as chocolate or tea) had no impact on the likelihood of developing rosacea.
Why is this important?
These results of this study are more than just interesting observations. If other research can confirm the findings, it could lead to a better understanding of why rosacea develops in some people and not in others. Because inflammation driven by the immune system is thought to play an important role in rosacea, insights into the development of this disease could extend to advances in other autoimmune disorders. Finally, many people with rosacea (or a family history of the disease) who like coffee may avoid it because of the widespread notion that coffee will make it worse. The findings of this study suggest that's not true.
There are always caveats
As with all research of this type, there are limitations to consider. For example, this study:
—only included women, most of whom were white — we'll need additional studies of men and other ethnic groups to know if the findings extend widely.
—relied on health surveys and study participants' memories regarding past diagnoses and diet; such survey data may not always be accurate.
—found a link between higher coffee consumption with lower risk of rosacea, but it cannot determine whether coffee consumption actually caused a reduction in rosacea.
The bottom line
Coffee is one of the mostly widely consumed beverages on the planet, and it's also among the most widely studied. While it can cause problems for some people (such as heartburn, tremor, or palpitations), it's a source of pleasure and enjoyment for millions. In addition, coffee has been linked with a number of health benefits, ranging from reductions in Type 2 diabetes and liver cancer to greater longevity. From this latest research, it appears that you can add the possible prevention of rosacea to the list.
(Robert H. Shmerling, M.D., is faculty editor at Harvard Health Publishing.)