The hottest new food trend is actually pretty old. Way, way old. The same whole grains grown by ancient Egyptians, Ethiopians, Aztecs, and Incas are shaking up the 21st century as they're now appearing in staples like Cheerios and Chobani yogurt, with many more products expected to hit the shelves in 2015.

Here are five grains from long ago that you need to know about, plus what to do with each one.

Amaranth (pictured)

Don’t let amaranth’s tiny size fool you. The Peruvian native is high in protein (nearly double the amount in brown rice), and offers all of the essential amino acids your body can't make on its own—so it's a complete protein, like meat, poultry, and eggs. It’s technically a seed, so it’s naturally gluten-free, and a perfect addition to vegan and gluten-free diets.

Try it: Pop it like popcorn in a hot, dry skillet and mix it into freshly baked granola, or stir into melted dark chocolate and freeze in mini muffin tins for a sweet, single-serve dessert.

Buy it: Arrowhead Mills whole grain amaranth ($10, amazon.com) or Bob's Red Mill amaranth flour ($13, amazon.com)

RELATED: 15 Healthy Gluten-Free Recipes

Millet

Millet was actually Asia’s staple grain before rice more than 10,000 years ago. These days, you may be more familiar with it as birdseed. It’s gluten-free and high in antioxidants and magnesium, which research suggests may help prevent and manage high blood pressure, heart disease, and diabetes. Since 60% of adults in the United States don’t consume the recommended amount of magnesium, millet may be just what’s missing from your healthy diet.

Try it: Serve up millet porridge instead of oatmeal or toast it in a hot skillet to bring out its nutty flavor. Sprinkle toasted grains on fresh fruit and yogurt, cereal, or salads.

Buy it: Arrowhead Mills whole millet ($4, amazon.com) or Bob's Red Mill millet flour ($3, amazon.com)

RELATED: 18 Health Benefits of Whole Grains

Spelt

Spelt is a type of wheat that was pushed aside during industrialization because it was harder to grow than the wheat that’s popular now. It’s rumored that wheat-sensitive people are better able to tolerate spelt, but because it contains gluten, it’s not safe for those with celiac disease or gluten sensitivity. One cup of cooked whole spelt is high in fiber (helpful for weight management) and a good source of iron for vegetarians.

Try it: If you don't like the bitter flavor of whole wheat in baked goods like muffins, you may prefer spelt flour’s sweeter, nuttier bite and lighter texture. Or toss cooked spelt berries into salads for a more filling lunch. Look for “whole spelt” on the label to ensure you’re getting the whole grain, not a refined version.

Buy it: Bob's Red Mill organic spelt berries ($4, amazon.com) or Arrowhead Mills spelt flour ($6, amazon.com)

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Teff

If you’ve ever tried Ethiopian food, you’ve had teff, which is used to make their famous spongy injera bread. It’s surprisingly high in calcium, with one cup containing as much as a half-cup of cooked spinach. Teff can also help with weight management: it’s rich in a type of fiber called resistant starch, which helps you feel more satisfied, feeds your healthy gut bacteria, and doesn’t raise blood sugar levels.

Try it: This gluten-free grain has a mildly sweet flavor (injera only tastes sour because it’s made with fermented teff), and makes a delicious hot cereal similar to farina. You can also substitute whole grain teff flour for ¼ of the all-purpose flour in a recipe.

Buy it: Shiloh Farms ivory teff ($6, amazon.com) or Bob's Red Mill teff flour ($12, amazon.com)

RELATED: 14 Non-Dairy Foods That Are High in Calcium

Kamut

An ancient cousin of modern wheat, kamut has 20-40% more protein and a sweeter, more buttery flavor. If you suffer from irritable bowel syndrome (IBS), a small 2014 study in the British Journal of Nutrition found that subjects eating products made with organic, semi-whole grain kamut reported a significant decrease in the severity of IBS symptoms like abdominal pain and bloating than when they ate products made with semi-whole grain modern wheat. Blood tests revealed reduced inflammation after the kamut intervention, but not after the modern wheat period.

Try it: Use whole grain kamut flour to make healthy pancakes, bread, and other baked goods or toss cooked kamut berries into a stir-fry or salad. There are many ready-to-eat products made with kamut already on the market like breakfast cereal, granola, and pasta.

Buy it: Bob's Red Mill organic kamut ($9, amazon.com) or Bob's Red Mill organic kamut flour ($4, amazon.com)

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