The main reason you’d want to use a filter on your bathroom sink is to protect the skin on your face and hands from hard water as you wash. But the thing is, hard water isn’t inherently bad; in fact, you might not even notice the hardness of your water unless you’re dealing with any dry or sensitive skin concerns. While some studies suggest having a soft water filter can help mitigate atopic dermatitis if implemented early, there isn’t evidence saying that soft water filters are essential for maintaining barrier health–especially compared to other methods.
Another caveat: It depends on where you live. “Water composition varies from region to region in the United States, and water filtration systems are becoming more and more popular. However, these systems can also accumulate contaminants such as microbes,” board-certified dermatologist Naana Boakye, M.D. MPH, tells mbg. That said, should you invest in a sink filter, be sure to clean it often–otherwise, it may collect even more contaminants and thus be worse for your skin in the long-run.
Finally, if you’re worried about water compromising your skin barrier, there are many other steps you can take to help keep it healthy. “The key to protecting the skin barrier is to take warm, short showers, use pH-balanced soaps, and apply moisturizers ideally twice a day,” Boakye says. See here for our full guide to taking skin microbiome-supporting showers.