Eating more than the recommended amount of salt disrupts the antibacterial function of a type of immune cell, research in mice and humans has found.
According to the American Heart Association (AHA), 9 out of 10 people in the United States consume too much salt (sodium chloride).
The Dietary Guidelines for Americans, which the Department of Health and Human Services publish, recommend that people consume no more than 2.3 grams (g) of sodium per day.
This amount is roughly equivalent to 5.8 g of salt, which would fit into a level teaspoon. The reason for the recommendation is that there is good evidence that excess dietary salt raises blood pressure, which is a risk factor for heart disease and stroke.