Conflicts going on all over the world and stories of “collateral damage” along with unintended death and destruction from “friendly fire” are very common. But would you believe that your salt habit may actually be prompting your body’s defense system to miss the target and injure your own body instead? Well a series of recent reports in the journal Nature are indicating just that. When I first read these reports, I almost fell out my chair. This is a whole new frontier in the ongoing exploration of why adding salt to our food is so lethal.
We call the defense system of our body the immune system. As when our body faces an external threat, most commonly from microorganisms, the immune system prepares its defense. Most of the time you are not even aware that this process is even happening—until it doesn’t work. You have heard of AIDs, the most well-known example of the failure of our immune system. The immune system is disabled by a virus infection, HIV, and the person affected could die from any number of ordinary infections.
There are other situations in which our immune system misfires or attacks our own body. Our body pays the price for these friendly fires, which occur quite regularly, with a long list of autoimmune diseases. At this point we know of more than 100 different autoimmune diseases affecting 50 million Americans. One in five Americans suffers from some form of autoimmune disease, one of the most common causes of chronic illness.
Here is an example of how autoimmune diseases progress. Did you or anybody you know ever have strep throat? You may recall how your pediatrician was concerned about aggressively diagnosing and treating that simple case of strep throat. That’s because our immune system prepares a defense against these bacteria by producing a certain special cell which in turn produces weapons capable of neutralizing the strep bacteria. Unfortunately, this weapon also attacks the tissue of the valves of the heart and sometimes even the kidney (friendly fire). You may remember this as rheumatic fever. In the process, the valves get damaged, eventually requiring heart valve surgery. As a heart surgeon who deals with replacing these valves, I can tell you without hesitation that this is a big, tough surgery. Damage to the kidneys isn’t any easier, since it can lead to kidney failure and dialysis.
So how does salt fit into this equation? In one of the recently reported studies, scientists found that multiple sclerosis, a well-known autoimmune disease, more readily manifests and accelerates on a high-salt diet. This is a very disturbing finding with extensive ramifications. The research came simultaneously from the prestigious institutions of MIT, Harvard and Yale Universities. At the center of these findings are special TH17cells belonging to the immune system. Researchers found that these TH17 cells, which are responsible for producing weapons against external aggression and which have been implicated in auto immune diseases, simply thrive in salty conditions.
In the words of the lead researchers Vijay Kuchero from Bringham and Women’s Hospital in Boston as reported by multiple media outlets, “If you incrementally increase the salt, you get generation after generation of these TH17 cells.”
Dr. Hafler from Yale University chimed in. “It was an easy experiment–you just add salt”.
Both Drs. Hafler and Kuchero found that a high-salt diet accelerated the multiple sclerosis in a mouse model.
The research is as disturbing as it is promising. These findings of connecting salt to autoimmune diseases could have an extraordinary impact on the course of widely prevalent autoimmune diseases. If only we could get ourselves to just stop adding salt to our food and stop this friendly fire.
For an up-to-date list of autoimmune diseases, visit the following web sites: