Just because something's called "salad" doesn't make it healthy -- in fact, it can be the exact opposite. Here's how to make your salad nutritious, tasty and filling:Keep it colorful. A salad with iceberg lettuce, celery and cucumbers has significantly fewer vitamins than one with romaine or spinach leaves, carrots, broccoli and tomatoes. "Generally, the darker and brighter the color, the better the nutrition," says Holly Hicks, a registered dietitian in Newport News, Va.Add lean protein. Without it, your stomach likely will be rumbling again soon. Good choices: grilled chicken breast or shrimp, lean beef, canned salmon, beans, baked tofu and hard-boiled eggs.