Eczema may sometimes be caused by eating too much salt

People with eczema have higher levels of sodium in their urine than those without the skin condition, with every additional 1 gram linked to an 11 per cent increase in the risk of a diagnosis

Eating too much salt has been linked to eczema after researchers found people with the skin condition have elevated levels of sodium in their urine.

More than 200 million people worldwide have eczema, which causes dry, cracked and itchy skin. Common triggers include irritants found in soaps and detergents, as well as environmental or food allergens. Previous research has also linked frequent fast food consumption to an increased risk of severe eczema in children.

To see if salt may play a role, Katrina Abuabara at the University of California, San Francisco (UCSF), and her colleagues examined urine sample data from more than 215,800 adults in the UK Biobank study, of whom more than 10,800 had eczema.

The researchers used a urine sample from each participant to estimate their urinary sodium excretion over 24 hours. About 90 per cent of dietary sodium is later excreted in urine, making the waste product a relatively reliable way of gauging someone’s salt consumption.

Overall, the study participants excreted an estimated 3.01 grams of sodium in their urine over 24 hours, on average. The recommended sodium intake for adults is typically around 2.5 grams per day, equivalent to 6 grams, or one teaspoon, of salt.