Kale makes a tasty, vitamin-packed stir-fry ingredient. This dish pairs the colorful veggie with scallops and chorizo. (Fotolia / September 11, 2013)

Every few months, it seems, there's hype about the latest, hottest superfood. But lots of ordinary foods, many of which are stocked in nearly every grocery store in America, are "superfoods" brimming with various disease-fighting nutrients, usually without providing too many calories.

The added bonus to eating more of these easy-to-find super-healthy foods? They won't break the bank. These 12 healthy foods clock in at under a dollar per serving and deliver a lot more nutritional bang for your buck than the offerings you'd find on fast-food dollar menus.

1. Lentils

Cost Per Serving (1 cup): 15 cents

Why lentils are so good for you: Like beans, lentils are high in fiber and protein (8 grams and 9 grams per half cup, respectively), which makes them great for your heart. They have the edge over beans, though, when it comes to preparation. Lentils cook up in only 15 to 30 minutes and don't need to be presoaked.

2. Oats

Cost Per Serving (1/3 cup, uncooked): 10 cents

Why oats are so good for you: They offer a great way to get soluble fiber in your diet (delivering 3 grams per serving). Research suggests that increasing your intake of soluble fiber by 5 to 10 grams each day could result in a 5 percent drop in "bad" LDL cholesterol. Quick-cooking oats are just as healthy as steel-cut. Just steer clear of oatmeal packets loaded with added sugars.

3. Kale

Cost Per Serving (1 cup): 60 cents

Why kale is so good for you: This veggie is an undisputed superfood. A single serving (1 cup cooked) has 10 times the daily value of bone-healthy vitamin K. It also has 3 times the daily value of vitamin A and is high in lutein and zeaxanthin, which all help your vision. Plus, it's pretty darn tasty.

4. Almonds

Cost Per Serving (1 oz.): 63 cents

Why almonds are so good for you: A 1-ounce serving (23 nuts, 162 calories) has 37 percent of your daily value for vitamin E--a nutrient many Americans fall short on. Almonds also deliver some calcium, fiber and folate. Not only that, a serving of almonds has as many flavonoids as a cup of green tea, according to a study in the Journal of Agricultural and Food Chemistry.

5. Tea

Cost Per Serving (1 tea bag): 10 cents

Why tea is so good for you: It's a super-healthy, budget-friendly addition to your diet. Both green and black tea are loaded with antioxidants, which may boost your immune system and promote heart health. In fact, scientists have found that those who drink 12 ounces or more of tea a day were about half as likely to have a heart attack as non-tea drinkers.

6. Oranges

Cost Per Serving (1 orange): 34 cents