Nutritional value involves both what a food contains and what it doesn't. For instance, the value of dietary protein, fiber, vitamins and minerals increases in the absence or low content of saturated fat and sugar. Fewer of these high-calorie nutrients mean fewer calories overall, making the nutrition in a healthy food more dense. Choose foods with high nutrient daily values, or DVs, of 20 percent or more per suggested serving, to achieve your U.S. Food and Drug Administration recommended allowances.
Spinach
Cooked spinach is one of the most nutrient-dense foods you can eat, with low calories and extremely broad nutrition, as reported by the U.S. Department of Agriculture. You must cook spinach leaves to concentrate their nutrients, but when you do, you'll receive 20 percent DVs and up of calcium, iron, magnesium, potassium and vitamins A, C and K, as well as several B vitamins, per 1 cup. Additional bonuses include 19 percent DV of vitamin E, 17 percent DV of dietary fiber, and 11 percent DV of protein. In addition, spinach is low in fat, with the majority of it being beneficial monounsaturated fat, and contains only 41 calories per serving.
Salmon
Salmon has a similar fat ratio to spinach, with the addition of heart-healthy omega-3 fatty acids, which may also protect against cancer. Relatively few foods provide high omega-3 content or vitamin D, of which a 3-oz. serving of salmon delivers more than 100 percent DV. When cooked without added fat, salmon makes a healthy source of over 20 percent DV of protein, magnesium and several B vitamins, within 184 calories. For these and moderate contributions of vitamin E, the American Heart Association suggests eating salmon and other fish in place of meat twice a week.
Yogurt
This condensed form of milk represents another healthy protein food with strong vitamin and mineral content, in low-fat or fat-free varieties. Yogurt is one of the strongest food sources of calcium. The USDA reports that 1 cup of fat-free yogurt has just 127 calories and more than 20 percent DV of protein, calcium and vitamins B2 and B12. Yogurt also contains moderate amounts of other B vitamins and potassium and other minerals.
Berries
Get your vitamin C and dietary fiber from any of several varieties of berries, plus additional antioxidants specific to each type. The USDA Nutrient Database ranks the nutritional value of these fruit in 1-cup servings. Strawberries, raspberries and blackberries all offer more than 50 percent DV of vitamin C, with blueberries providing about half that much. Raspberries and blackberries have the highest fiber, at over 20 percent DV, while strawberries and blueberries have about half the fiber of other types of berries.
