Sodium Intake Linked to Increased Risk of Dry, Itchy Skin
Family history and allergies are known risk factors for chronic skin diseases like eczema. These conditions can be worsened by environmental factors such as pollution, cold weather, hard water, and certain cosmetics. Now, new research from the US highlights a common food ingredient that may also increase the risk of dry, itchy skin: sodium.
According to the French Institute of Health and Medical Research (INSERM), atopic dermatitis (or atopic eczema) is a chronic inflammatory skin disease characterized by dry skin and eczema-like lesions. Both genetic and environmental factors contribute to its development, and the condition can significantly impact mental health. The prevalence of this chronic disease has been rising, especially in industrialized countries, due to changes in the environment and lifestyle.
A research team from the University of California, San Francisco (UCSF) explored the impact of sodium on skin dryness and itching, specifically in relation to eczema. They analyzed data from 215,832 adults aged 37 to 73 from the UK Biobank, focusing on the amount of sodium excreted in urine and its correlation with eczema diagnoses.
The study, published in JAMA Dermatology, found that each additional gram of sodium excreted in the urine over a 24-hour period was associated with an 11% increase in eczema diagnoses, a 16% increase in eczema cases, and an 11% increase in chronic disease severity.
Half a Teaspoon of Salt
To support these findings, researchers also examined data from 13,014 American adults in the National Health and Nutrition Examination Survey. They found that consuming an extra gram of sodium per day — equivalent to half a teaspoon of table salt — was associated with a 22% higher likelihood of having an active case of eczema.
The study suggests that reducing salt intake could help manage eczema flare-ups. “Most Americans eat too much salt and can safely reduce their intake to recommended levels,” says Dr. Katrina Abuabara, associate professor of dermatology at UCSF. “Eczema flares can be difficult for patients, especially when they are unable to anticipate them and don’t have recommendations on what they can do to avoid them.”
For those suffering from eczema, monitoring sodium intake could be a crucial step in managing their condition.