Over the last millennium, salt has undergone a major status shift, from exotic delicacy that drove humans to war to kitchen condiment taken so for granted that 90 percent of Americans consume too much of it without even trying. But new research suggests that salt may be on the verge of yet another reinvention—this time in the world of disease control.
Superbugs like Methicillin-resistant Staphylococcus aureus, or MRSA, have wreaked havoc on the health-care system in recent years. Drug-resistant infections, which include superbugs, are responsible for more than 700,000 deaths globally each year, and come with an approximate annual cost of $20 billion in the United States alone. How do you stop them? Frequent hand washing is one option, but that requires a behavior change, which can be difficult, even for hospital staff. Another option is to coat those frequently fondled objects most likely to carry the bugs—doorknobs, bed rails, toilet handles—with a special anti-microbial surface, like copper. This approach is increasingly popular, but time is of the essence when it comes to preventing the spread of disease, and MRSA has been shown to survive even on copper for several hours.
Who knew salt could be up for the job? Well, butchers, for one, who have used it to fight off pathogens like Salmonella for centuries. And it was a casual conversation with a former butcher that led Brayden Whitlock, a graduate student at the University of Alberta, to design a pilot study that put salt and copper head to head. Coupon-sized strips of pure, compressed sodium chloride were covered in an MRSA culture, alongside similar strips of antimicrobial copper and stainless steel. Whitlock found that salt killed off the bug 20 to 30 times faster than the copper did, reducing MRSA levels by 85 percent after 20 seconds, and by 94 percent after a minute.