How to Know What’s Really a Nut (And What Isn’t)

You’ve probably eaten peanuts at a ball game, sprinkled almonds on a salad, or grabbed a handful of pistachios as a snack. But here’s the twist—most of the foods we call “nuts” aren’t nuts at all.

According to Live Science, the nut aisle is full of impostors. Let’s take a closer look at what truly qualifies as a nut and what doesn’t.

What Is a True Nut?

In botanical terms, a true nut is a dry fruit with one seed that is fully enclosed in a hard shell. The key detail? That shell doesn’t naturally open to release the seed. This makes nuts different from other fruit types that split open when ripe.

One of the few common examples of a true nut is the walnut. Hazelnuts and chestnuts also fit the definition. These develop from a single ovary, have one seed, and don’t crack open on their own.

Peanuts: Not Even Close

Despite their name, peanuts are not nuts. They grow in the ground, not on trees, and they form in pods, similar to peas and beans. Each pod usually contains two seeds—the peanuts we eat. This makes peanuts part of the legume family, not the nut family. Like snow peas or lentils, they are plants that produce seeds inside a pod.

Almonds, Cashews, and Pecans: Not Nuts Either

These popular “nuts” are actually drupes. A drupe is a fruit with a fleshy outer layer and a hard inner shell (called a pit) that surrounds a seed.

If that sounds like a peach or cherry, you’re right—those are drupes too. The difference is which part we eat. With peaches, we eat the soft outer flesh and throw away the pit. With almonds, cashews, and pecans, we remove the outer flesh and eat the seed inside the pit.

So What Are You Really Eating?

True nuts: Walnuts, hazelnuts, chestnuts

Legumes: Peanuts

Drupes: Almonds, cashews, pistachios, pecans

In everyday language, “nuts” has come to mean any hard-shelled seed used as a snack or ingredient. But if you’re going by the science, your snack mix is likely full of fruits and legumes, not nuts at all.