It’s not uncommon for people who feel overly itchy to blame the irritation on dry skin or some kind of allergic reaction. However, that urge to scratch might not have anything to do with a physical catalyst—and could have more to do with the amount of anxiety you’re carrying around. New research suggests that stress might be one of the things that’s making you feel itchy and sheds some light on just why this is the case.
RELATED: Stress Relief Supplement Is Safe to Use and "Very Effective"—But Doctors Urge Caution.
A new study links stress and itchy skin.
A new study published in the Journal of Allergy and Clinical Immunology used mice to study the relationship between psychological stress and allergic symptoms by looking primarily at immunoglobulin E (IgE) antibodies.
As the American Academy of Allergy Asthma & Immunology (AAAAI) explains, lgE antibodies are produced by the immune system when you're exposed to an allergen such as dust or pollen. "These antibodies travel to cells that release chemicals, causing an allergic reaction. This reaction usually causes symptoms in the nose, lungs, throat, or on the skin," they write.
To carry out the experiment, the team exposed some of the mice to stress before triggering an allergic response in all of their ears, notes a press release. They observed that the stressed-out group of mice exhibited worse displays of an allergic reaction than the relatively calm cohort, including a noted decrease in anti-inflammatory programmed death ligand 2 (PD-L2)-positive macrophages, a type of white blood cells that typically remove dead skin cells from the site of an allergy response.
The stressed-out mice also had an increase in eosinophils—a type of white blood cell the body uses during allergic reactions, according to Cleveland Clinic. The team said this spike actually worsened the reaction in the animals.
The researchers also found that it wasn’t just stress in the moment that led to worse reactions.
"Our findings suggest that the impact of psychological stress on immune cells is long-lasting and can even affect macrophages that differentiate later," Soichiro Yoshikawa, PhD, an associate professor at Juntendo University and one of the study’s authors, said in the press release. "This phenomenon, referred to as 'stress memory,' implies that severe stress leaves a lingering imprint on immune cells, influencing their function and contributing to disease development."
RELATED: What Happens If You Take Benadryl Before Bed Every Night, Doctors Say.
Other studies have made the connection between stress and scratching.
The latest research adds to a mounting body of evidence that there’s a connection between anxiety and itchiness. One 2015 study found that subjects with a chronic itching condition became itchier when they were shown stress-inducing images, including a person being rescued from a fire or about to be bitten by a snake. Other research has found that anti-anxiety medications and some forms of therapy can also help reduce the feeling of needing to scratch.
Fortunately, researchers from the latest study also followed up their results with a potential solution. Data showed that while a protein known as CCL24 led to an increase in eosinophils, applying a caspase-1 inhibitor helped reduce swelling in the rodents’ ears. The authors said this was a "promising" approach for treating skin allergies.
The takeaway:
A new study supports the link between stress and itching. In the experiment, mice exposed to stress showed worse allergic skin reactions than those not made anxious. But even with a potential treatment for the more immediate topical issue, the team concluded that their findings could have larger implications.
"Anti-inflammatory macrophages play crucial roles in various diseases, including cancer, autoimmune disorders, and wound healing,” Yoshikawa said in the press release. "This study not only sheds light on the impact of stress on allergic inflammation but also lays the groundwork for exploring how stress exacerbates other diseases involving these macrophages."
