So, go with a low-calorie, fat-free dressing, right? Think again. To make up for flavor, they’re often loaded with extra sugar and sodium. Fat makes salads tastier and healthier. Your body needs it to take in and use certain vitamins, like A, D, E, and K. One study found that people got fewer antioxidants called carotenoids when they ate salads with fat-free dressing, compared with reduced- or full-fat dressing.