Wired On average, the typical American contracts two to three colds per year between September and May, at an estimated cost of around $40 billion to the economy. Effective forms of treating or preventing colds have proven hard to come by, with the majority of over-the-counter medicines yielding modest results; it’s hard to devise a drug that tackles the vast array of viral pathogens that cause them. The need for better respiratory protection during the winter months is clear. It might be found in a practice that dates back thousands of years.
The concept of saline nasal irrigation, or bathing the nasal passages with a saltwater solution, is thought to have been introduced as part of Ayurveda, an alternative medicine system that originated in the Indian subcontinent more than 5,000 years ago. Now, modern science is beginning to demonstrate that this ancient practice really does serve as a surprisingly effective shield against many of the seasonal bugs behind the common cold. In 2024, a major new study of nearly 14,000 people funded by the National Institute for Health and Care Research in the UK found that using a simple saline-based nasal spray between three and six times a day at the first sign of an infection reduced illness duration by around 20 percent. A follow-up study, published last year, reported similar benefits.