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Salt Unbalances the Immune System

Too much salt in food can push the immune system out of balance, according to a new study published in the Journal of Clinical Investigation.

A team of researchers led by Dr Katrina Binger of the Baker IDI Heart and Diabetes Institute observed a link between excess salt consumption by rodents and delayed healing of their wounds due to reduced immune cell activity.

Binger’s group found that too much salt in food weakens type 2 macrophages, which are the first responders to infection and play a critical role in repairing wounds and combating excessive levels of inflammation. Wound healing was delayed in rodents fed a high-salt diet, in part because of the salt-related weakening of these particular scavenger cells.

At the same time, previous studies by Binger’s team have shown that cells that cause inflammation responded positively to a higher salt intake. The overall result of these seemingly contradictory studies is that salt pushes the immune system out of balance by boosting inflammatory cells while inhibiting cells that stop inflammation, such as type 2 macrophages.

“The clinical implications of this research are that eating too much salt doesn’t just elevate blood pressure – it compromises the balance of the immune system to directly cause chronic diseases,” Binger said. “Dietary salt restriction is a neglected therapeutic option, which could now be looked at for a number of different diseases, such as type 2 diabetes, rheumatoid arthritis and multiple sclerosis.”