it’s a paradox. Low sodium diets are usually for high blood pressure. Healthy foods usually lower blood pressure , you can’t have both and be healthy.
Low carb diets reduce insulin, which in turn can increase salt secretion through the kidneys, This can reduce the requirement for a low salt diet, or may mean more salt is required.
If you are asking because you are on a low salt diet, then you need to see your doctor before embarking on a low glycemic index diet, as meds plus diet may reduce salt too much, on the other hand your doctor may be able to wean you off the medication if you are going Low carb,