It’s drummed into our heads. Salt bad, salt bad, salt bad. But why! A new study in the Journal of Nutrition claims salt decreases levels of an enzyme called nitric oxide synthase (NOS). NOS signals nearby muscles to relax, which improves blood flow and reduces high blood pressure. First, using bovine cells, scientists observed a decrease in NOS activity with an increase in salt concentration and similar results were observed using Chinese hamster ovary cells; Food Navigator reports.