Drenching salads with bottled dressing is pretty much akin to sprinkling salt on your mixed greens since most dressings pack as much as 300 to 500 mg sodium in a 2-tablespoon serving. And most of us don’t stop at just 2 tablespoons. But the core ingredients in salad dressing, oil and vinegar, are sodium free. Mix the two with a dab of mustard, any kind works but Dijon is the usual choice, and the sodium numbers are so minimal it’s not even worth counting.Kitchen tip: Whisk together 1 tablespoon olive oil, 1 tablespoon vinegar and 1/4 teaspoon Dijon mustard for a low-fat vinaigrette. Optional add-ins: dried herbs, chopped shallots, lemon zest, fresh ground pepper. See how step-by-step in Making a Basic Vinaigrette.