Common Colds and Saline Nasal Irrigation
On average, Americans catch two to three colds each year between September and May, which costs the economy around $40 billion. Finding effective ways to treat or prevent colds has been challenging. Most over-the-counter medications deliver only modest results, likely due to the variety of viral pathogens involved. Clearly, there’s a pressing need for better respiratory protection during the colder months, and surprisingly, this may be found in an ancient practice.
Saline nasal irrigation, which involves rinsing the nasal passages with a saltwater solution, has roots in Ayurveda, a traditional medicine system originating in India over 5,000 years ago. Recent scientific investigations are starting to show that this age-old technique is surprisingly effective in guarding against many seasonal viruses linked to the common cold.
A significant study in 2024, involving nearly 14,000 participants and funded by the UK’s National Institute for Health and Care Research, revealed that using a saline nasal spray between three and six times a day at the onset of an infection could shorten the duration of illness by about 20 percent. A follow-up study published last year reported similar findings.
According to Paul Little, a primary care research professor at the University of Southampton who led both studies, sodium chloride (or salt) stimulates a natural antiviral response in the nasal passages. “The chloride in saline is absorbed by the cells in the nose and throat,” he explains, “and is transformed into hypochlorous acid in those cells, which then inhibits viral replication.” This process apparently lowers the viral load in the nose.
Historical reviews indicate that western medicine has looked into saline nasal irrigation since the 19th century, but it has often faced skepticism. During the early Covid pandemic, some healthcare professionals quickly dismissed the idea that saline nasal irrigation could prevent infections. Initially, it was listed among other debunked treatments on the World Health Organization’s webpage about Covid myths, but it was later removed as more studies emerged showing its potential benefits.
One study found that individuals using saline nasal irrigation for two weeks after a Covid positive test had over an eightfold lower chance of being hospitalized, rekindling interest among medical professionals regarding its effectiveness against other seasonal illnesses.
David Rábago, a physician and professor at Pennsylvania State University College of Medicine, shares, “Clinicians and researchers are now taking a closer look at saline nasal irrigation because it’s helpful, natural, and easy to understand.” The results from various smaller studies, as well as a few larger ones, suggest that saline nasal irrigation is both safe and effective.
Beyond preventing viral replication in nasal cells, saline seems to enhance the activity of neutrophils, a type of white blood cell that fights off germs, while also improving the capacity of mucus to trap viruses. Amy Baxter, a pediatrician and assistant clinical professor at Augusta University, explains, “When mucus is adequately hydrated, it creates a barrier that envelops a virus, allowing it to be swallowed or coughed up.” It’s somewhat akin to how soap works—it encases dirt, making it easier to wash away.
