SOFTER trial investigating if water softeners can prevent eczema

This article was first published in the March 2019 edition of National Eczema Society’s membership magazine, Exchange.

“An ounce of prevention is worth a pound of cure.” Benjamin Franklin

The Softened Water for Eczema Prevention (SOFTER) trial has been launched to investigate whether using water softeners can reduce the risk of eczema in babies.

The trial is led by Professor Carsten Flohr, Consultant Dermatologist at Guy’s and St Thomas’ NHS Foundation Trust in London, and builds on findings from Professor Flohr’s team, published in 2017, showing that hard water damages the skin’s protective barrier and could contribute to the development of eczema. Observational studies have also shown that living in a hard water area increases the risk of having the condition.

‘The new study is exciting because it is the first time that researchers are looking at the effect of using water softeners on babies in their own homes,’ says Professor Flohr.

‘SOFTER builds on research published last year which found that eczema may be caused by hard water damaging the skin’s protective barrier. However, that study took place in a lab setting, focused on adults and was not randomised, so we hope that the SOFTER trial will give us a greater insight into whether water softeners can help infants avoid getting eczema, and allow us to gain more knowledge about the impact of hard water on babies’ skin.’

The team aims to recruit 80 pregnant women who live in hard water areas to the SOFTER trial if their unborn child is at high risk of having the condition, for instance if they have a parent or sibling with eczema, asthma or hay fever. As part of the trial, the women are randomised either to have a water softener installed in their homes or not. They will use either the softened or unsoftened water to wash their babies depending on the group that they have been assigned to.

The researchers won’t know which of the women had a water softener installed in their baby’s home and which didn’t.

They will look at a number of measurements in the babies’ skin, including water loss, pH levels, detergent deposits and skin bacteria. These will be taken from the babies at birth, 1 month, 3 months and 6 months to check for any changes to their skin.

It is hoped this initial trial will lead the way for a larger-scale trial across the uk involving hundreds of people.

Building on earlier findings

The SOFTER trial builds on earlier findings that exposing the skin to hard water damages the skin barrier – which is our defence against outside threats such as bacteria or sun burn – and increases the sensitivity of the skin to potential irritants found in everyday wash products such as soap or washing powder.

Skin pH is normally acidic, but hard water has high alkalinity, which means it can raise the skin surface pH. A shift towards an alkaline pH disturbs the skin’s natural function as a physical barrier and leaves it prone to the growth of potentially harmful bacteria, which can cause infection.

What’s more, hard water contains high levels of substances that bind to surfactants – such as sodium lauryl sulphate (SLS) and sodium lauryl ether sulphate (SLES) – in wash products, making them insoluble, so they settle on the skin. Researchers found that using a water softener reduces the harmful effects of surfactants, potentially decreasing the risk of developing eczema.

Funding: the trial is being funded by the National Institute for Health Research (NIHR) at guy’s and St Thomas’ Biomedical Research Centre (BRC). The water softeners are being provided by Harvey Water Softeners.

Collaborators: these include the university of Nottingham, the University of Sheffield, the University of Amsterdam, the US National Institutes of Health and the Skin Research Institute of Singapore (SRIS), a collaboration between the Agency for Science, Technology and Research (a*staR), National Skin Centre (NSC) and Nanyang Technological University (NTU).