The 20 fittest foods: we count down the absolute best foods you can pile on your plate. How does your diet stack up?

Of all the fruit you can eat, blueberries may be the absolute best. Whether you're getting them raw, tossed into cereal, or mixed in fruit salad or a smoothie, blueberries pack more fiber, vitamins, and minerals per ounce than any other fruit in the produce aisle. Chief among those nutrients are free-radical-fighting antioxidants. Free radicals, which increase in number as you get older, travel around your body damaging cells, promoting disease, and triggering signs of premature aging. And blueberries harness the firepower to knock them out of service.

Need another reason to eat them? How about your memory? Those same antioxidants that fight disease are also effective in helping keep connections between cells in your brain and nervous system healthy, ensuring clearer, quicker thinking and the best memory possible.

1 SALMON 121 CALORIES PER 3-OZ SERVING EAT 3-4 SERVINGS PER WEEK

Salmon tops our list for a number of reasons, but the biggest has got to be because it's so densely stuffed with omega-3's. These fatty acids are thought to slow memory loss as you age and boost heart health by regulating heart rhythms and keeping arteries and veins supple and free of blockages. While saturated fats lead to obesity, the polyunsaturated fatty acids in fish appear to reduce and prevent obesity, according to a study published in Clinical Science.

And that's just the tip of the iceberg. Salmon is also an excellent source of protein. A three-ounce cooked serving contains 20 grams--making it ideal for building muscle and trimming fat. Besides helping stimulate your metabolism three to four times more than carbs or fat, protein is the absolute best food for helping fill you up, so you take in fewer calories and burn more. And that's what being a fit food is all about.