Sodium Intake Linked to Atopic Dermatitis and Disease Severity

Atopic dermatitis (AD), the most common form of eczema, affects millions of people worldwide. Characterized by inflammation, skin dryness, itch, and rash, its exact cause remains unknown. However, a recent study provides compelling evidence linking higher dietary sodium to increased risk and severity of AD.

Understanding the Study

A cross-sectional study by Chiang and colleagues, published in the Journal of the American Medical Association Dermatology, involved 215,832 participants aged 30 years and older from the UK Biobank. The study focused on 24-hour urine sodium excretion as a biomarker, adjusting for factors like body mass index, sex, age, and other urinary concentrations.

The study found that participants with a higher average sodium excretion—around 3.01 grams per day—had a significantly increased risk of developing AD. Specifically, a one-gram rise in sodium excretion correlated with an 11% higher chance of AD, a 16% higher risk of active AD, and an 11% higher likelihood of severe AD.

The Role of Sodium in AD

Research indicates that sodium stored in the skin can stimulate the immune system, leading to increased inflammation. This hyperactivation of the immune system is a hallmark of AD, suggesting that excess sodium may be a contributing factor to its development and severity.

Prevalence of Atopic Dermatitis

According to GlobalData epidemiologists, the number of people diagnosed with AD is projected to rise from 42 million in 2024 to about 42.5 million by 2033 across the 7MM (France, Germany, Italy, Japan, Spain, the UK, and the US). Approximately 85% of these cases are mild to moderate, while 15% are severe.

Implications for Treatment and Prevention

The findings of this study suggest a new, potentially accessible intervention for AD: reducing dietary sodium intake. This simple lifestyle change could be a cost-effective method to improve patient outcomes and enhance quality of life.

While additional research is necessary to validate these findings and explore the underlying mechanisms, the study represents a significant step forward in understanding and managing AD.