High Salt Intake Increases Eczema Risk, UCSF Study Shows

A recent study conducted by the University of California at San Francisco (UCSF) has indicated a potential link between high salt intake and the risk of developing eczema in adults. Eczema, also known as atopic dermatitis, is a skin condition that causes inflammation and itchiness. It affects approximately one in ten Americans, though its exact cause remains unknown, according to the National Institutes of Health. 
 
The research was published in JAMA Dermatology on Wednesday and could pave the way for further studies into how dietary factors like salt may contribute to this common skin condition. 
 
"We really wanted to understand triggers for atopic dermatitis," said Katrina Abuabara, an associate professor of dermatology at the UCSF School of Medicine who led the study. She noted that there's been an increase in eczema prevalence over time that "can't be explained by genetics alone.". 
 
According to their results, those consuming high-salt diets had a slightly increased risk, although more research is needed to solidify these findings. One possible explanation offered by Abuabara is that sodium found within our bodies can trigger inflammation, which has been linked with eczema through epidemiological data. 
 
In 2013, another study found children regularly eating fast food—typically high in salt—were more likely to suffer from eczema. However, as Abuabara points out, fast food contains many other ingredients, which could potentially explain this correlation too. 
 
"I don't think all eczema is related to salt," she said. "I think this is one piece of something that's probably a trigger for some people." 
 
Abuabara plans on researching whether reducing sodium intake can lessen severity or occurrence rates among sufferers: “We're doing more work before we can specifically recommend that or recommend a particular diet." 
 
While it must be stressed that these findings do not definitively prove causation between salt consumption and developing eczema but rather indicate an association, the study's participant demographic was predominantly white (95%) and from the U.K. Biobank, which typically contains older and healthier volunteers than the general population. 
 
The National Eczema Association and the National Institute on Aging provided funding for this research. Abuabara has also received research or consulting fees from several pharmaceutical companies, including Pfizer, La Roche-Posay, Sanofi, Nektar, Amgen, and Target RWE. 
 
Saranya Wyles of Mayo Clinic’s regenerative dermatology lab commended these findings as a good starting point for further hypothesis generation but cautioned that they are based on a one-time urine sample and not definitive: "We have to be cautious of how it's interpreted." 
 
Bruce Brod at the University of Pennsylvania’s Perelman School of Medicine noted that while eczema is most common in children, participants in this study were adults with an average age of 56 years old. "It's hard to change treatment paradigms based on this study," he said, but recognized its potential contribution to future bio-epidemiologic studies. 
 
Brod explained that factors such as bathing frequency, environmental conditions like temperature or humidity where someone lives, and exposure at home or work all play roles in skin barrier function—key to understanding eczema development. 
 
Wyles added that other triggers can include tobacco smoke pollution and certain fragrances found in skincare products. She recommends regular moisturizing for skin barrier protection, especially if you are suffering from active inflammation where topical steroids may prove beneficial; severe cases may require oral or injectable medication.