The most common food seasoning may stop you from walking
Salt or sodium chloride may be the most common seasoning in our diet that could destroy health to cause Type 1 Diabetes, rheumatoid arthritis, multiple sclerosis, psoriasis, celiac disease and a host of other autoimmune disorders. A new study shows salt might be responsible for an increase in diseases that destroy autoimmunity.
Researchers know autoimmune diseases that develop when the body's immune system mistakenly attacks healthy tissue and organs are on the rise in the Western world. The thought is the increasing incidence might be from lifestyle and dietary factors.
A team of scientists from the U.S. and Germany have been looking at how salt in our diet, which is liberally added to packaged and pre-prepared foods, might be an environmental link responsible for increases in rates of autoimmune diseases that they say cannot be explained by genetic causes.
Researchers discovered several years ago that excess salt accumulates in tissues to set up a series of reactions that produces an inflammatory response, much like what happens when the body is infected - and in cases of multiple sclerosis and other diseases that remain a mystery.
What does salt do to the immune system?
Sodium chloride, which is the main constituent of salt, increases a type of immune fighting T-helper cells known as Th17. The cells help fight infection, but have recently been implicated as playing a role in autoimmune diseases.
Too much salt can make blood vessels stiffer, leading to heart disease, especially for 10 to 20 percent of the population who are salt sensitive.
Dr. Markus Kleinewietfeld of Yale University who participated in the research said in a press release, "In the presence of elevated salt concentrations this increase can be ten times higher than under usual conditions. Under the new high salt conditions, the cells undergo further changes in their cytokine profile, resulting in particularly aggressive Th17 cells”; discovered by the scientists in cell cultures.
Sodium chloride accelerated changes of T-helper cells into Th17 cells that are pathogenic.
In mouse experiments, too much salt induced an experimental form of autoimmune encephalomyelitis that is a model for multiple sclerosis. The researchers found a high salt diet increased numbers of TH17 cells dramatically.
“These findings are an important contribution to the understanding of multiple sclerosis and may offer new targets for a better treatment of the disease, for which at present there is no known cure," said Ralf Linker, head of the Neuroimmunology Section and Attending Physician at the Department of Neurology, University Hospital Erlangen. His hope is to use laboratory findings based on the study finding to help patients.
The finding doesn't prove salt is the culprit for autoimmune disorders like multiple sclerosis and rheumatoid arthritis that can lead to autoimmune diseases like MS or rheumatoid arthritis. The researchers note there are a host of environmental and genetic causes and that autoimmune dysfunction involves a complex process. An area of scientific interest is finding out if psoriasis symptoms might improve in patients who lower their salt intake. You can learn more about autoimmune diseases here.
*Sodium Chloride Drives Autoimmune Disease by the Induction of Pathogenic Th17 Cells"
Markus Kleinewietfeld, et al.
Nature (2013) doi:10.1038/nature11868
March 6, 2013