Your efforts in making a healthy salad will be in vain if you choose to top your salad with a dressing that's high in fat and calories. So, make it a habit to pick the low-fat or fat-free dressings at the market.

If calories aren't a major concern, you may want to use a dressing containing olive oil. Olive oil is 100 percent fat, but very little of it is saturated fat---the kind that causes heart disease. Use olive oil in moderation. One teaspoon of olive oil has 125 calories, more than what an entire salad contains. That's why many use olive oil in conjunction with vinegar. Vinegar has only a trace of calories but adds a bit of zesty flavor.