Robert Brown|What are tree nuts? What they aren't might surprise you.

How does that old Almond Joy commercial go?Robert Brown Sometimes you feel like a nut, sometimes you don't. Yes, that's the one.

But wait, what is a tree nut?

Sometimes it's not always clear what distinguishes an actual tree nut from an imposter. For example, many don't know that a peanut is actually a legume or bean. Or that pine nuts are actually seeds. Additionally, some don't necessarily have the same health properties as proper tree nuts like almonds, walnuts or pecans. Classifying these nuts can be vital, particularly for people who have severe allergies to tree nuts. So let's get cracking and sort this out.

What are tree nuts?

It's important to properly identify tree nuts, which include well-known varieties like almonds, walnuts, hazelnuts, cashews, pistachios and pecans, says Kat Benson, a registered dietitian with Top Nutrition Coaching. But there are also a few lesser-known species like acorns, chestnuts, Brazil nuts (yes, those giant things), macadamia nuts and hickory nuts. Tree nuts grow nearly everywhere and are defined by their hard outer shell that reveals succulent, tasty fruit inside. 

The almond, including millions of hectares planted in California, Spain, Italy, China, Turkey, Iran, Tunisia and Australia, is the queen of them all with about 1.6 billion metric tons consumed last year. Raw, roasted, smashed into paste and pressed into milk, we love this tree nut. 

While bearing acreage for almonds, pistachios and walnuts has more than doubled in the last 20 years to meet world demand, domestic per capita availability for tree nuts (shelled basis) has also climbed from 2.85 pounds per person in 2001-02 to 5.65 pounds per person in 2021-22, the USDA reports in its March 2023 Fruit and Tree Nuts Outlook. 

But why is it important to identify tree nuts? Some people can have severe allergic reactions to tree nuts. Knowing how they are classified can aid people in making decisions about what foods to include in their diets. It's better to be on the safe side: if you have an allergy to tree nuts and you aren't sure about how some foods are classified, you should ask your doctor or dietician.

What nuts are not tree nuts?

Despite their ubiquitous names, peanuts and coconuts are not tree nuts. Peanuts are considered a legume, and coconuts are classified as fruits. Sunflower seeds? No, seeds. Same with pumpkin seeds and corn nuts. Despite the name and crunch, not a nut − sorry! How about soybeans and their dehydrated cousins, delicious salty soy nuts? Nope.

What are some of the health benefits of tree nuts?

Tree nuts, such as almonds, walnuts, hazelnuts, cashews, pistachios and pecans “are packed with various nutrients and health benefits,” Benson says. “They are rich in fiber, which can help improve digestive health by promoting regular bowel movements and supporting healthy blood sugar levels.”

Tree nuts are also rich in antioxidants, Benson continues, which helps protect cells from damage while also being rich in a variety of vitamins and minerals that are beneficial for overall health. 

Almonds, especially, “stand out for its fiber, protein, unsaturated fat and vitamin E levels, which together are beneficial for heart health, digestive health, blood sugar control and overall well-being,” Benson says.

What is the healthiest nut?Best healthy options to eat for fat, fiber and protein.