Is A Peanut A Legume? Why This Classification Can Drive You 'Nuts'

Oluniyi Akande
Feb 29, 2024 By Oluniyi Akande
Originally Published on Nov 24, 2021
Peanuts in nutshell on a piece of wood and peeled peanuts in golden bowl on sackcloth
Age: 3-18
Read time: 5.1 Min

People often categorize peanuts as nuts because of their name.

Despite the 'nut' in peanuts, a peanut is actually categorized under legumes. Legumes are edible seeds or seed pods of a leguminous plant.

The word leguminous is used as an adjective to describe the Fabaceae or Leguminosae family of plants. They are commonly referred to as the legume family. This family of plants contains trees, shrubs, and vines.

Leguminous plants, such as peanuts, are natural fertilizers and are often grown parallel to food crops to supply the soil with nutrients like ammonium, protein, and nitrogen. While the peanut seed (legumes) is eaten by humans, the rest of the plant including the foliage (leaves) is used as livestock feed or as a fertilizer for food crops.

But why do we classify peanuts as legumes, and do they really grow underground? Read on to feed your growing curiosity!

You may also be interested in these fun fact articles about how peanuts are grown and where peanuts come from.

Which nuts are actually legumes?

Soya beans (Glycine max), chickpeas (Cicer arietinum), peas (Pisum sativum), peanuts (Arachis hypogaea), tamarind (Tamarindus indica), lentils (Lens culinaris), and pecans (Carya illinoinensis) are a few examples of the Fabaceae family.

The edible seeds of these plants such as peas and beans are called legumes. Therefore, peanuts come from the peas and beans family rather than from the tree nuts family such as walnuts and hazelnuts.

Legumes contain a high amount of minerals and nutrients like calcium, iron, phosphorous, potassium, and zinc. They are also rich in fiber and B vitamins. They also have a low fat content and low amounts of cholesterol.

Why is a peanut a legume and not a nut?

Peanuts and tree nuts are not the same. But for the sake of usage and culinary purposes, they have been named nuts. True nuts are a fruit with an edible kernel that is protected by a hard shell that never opens to release the seed. In contrast, the shells of peanuts open to release the seed.

Peanuts are also known as groundnuts because of their habit of ripening underground. This phenomenon is called geocarpy. It is a very rare form of plant reproduction. After the pollination of the flower, the ovary (known as peg) enlarges and grows into a small stem reaching downwards. The fertilized ovule of the peanut plant is in the tip of the peg which then penetrates the soil and later, matures into a pod.

However, peanuts are not the only legume to grow underground. Another legume, known as the Barbara groundnut, also has a tendency to grow underground.

These groundnuts should not be confused with other edible food grown underground like potatoes or carrots. They all come from different plant families. Potatoes, carrots, and turnips are all root vegetables whereas peanuts are legumes.

Are peanuts good for vegetarians?

The trend of vegetarian and vegan food has taken over the consumer market in recent years due to their cruelty-free nature. Many Americans have shifted to an environmentally conscious plant-based diet.

Peanuts are considered extremely nutritious for vegetarians and vegans. They are loaded with fiber and essential plant-based protein. Unlike other nuts like cashews, they do not contain saturated fat. They are also a healthy source of B vitamins, and other micro-nutrients like calcium and potassium.

As always, it is important to go through the label to understand whether they are completely vegetarian or not.

A variety of nuts in wooden bowls

Why do vegetarians love peanuts?

Ground peanuts are a great source of plant-based protein, fiber, minerals, and other nutrients. You can easily add nuts, seeds, and oils to your daily food recipes to create a balanced diet.

There are a variety of peanut food products and by-products available in the market such as peanut butter, peanut sauce, peanut oil, roasted peanuts, and peanut flour. These products can be later used to make by-products like peanut butter cakes, peanut pastries, and peanut flour muffins.

Living With A Peanut Or Tree Nut Allergy

Nuts like hazelnuts, cashews, walnuts are called tree nuts because they grow on trees. However, peanuts and tree nuts are not from the same family. Peanuts are classified as legumes, and they grow underground.

Even with such versatile properties, peanuts can be dangerous to some people. People with food allergies, especially peanut allergies or tree nut allergies, might be intolerant to eating peanuts. Tree nuts and peanut allergies are very common. Though, if you have a tree nut allergy, it doesn't necessarily mean that you are at the risk of being allergic to peanuts and vice versa.

In some cases, even traces of the allergen can trigger allergic reactions. In any food allergy, the person reacts to a certain protein found in the food item. Symptoms of any food allergy include vomiting, stomach pains, swelling around the mouth, diarrhea, and hives. In worse situations, it can also lead to difficulty in breathing and talking, tightness of the throat and tongue, dizziness, and rapid coughing.

You will know you have a peanut allergy (or tree nut allergy) if you experience any of these symptoms within 30 minutes of consuming a peanut-based food item.

In case of possible food allergies, it is best to consult a doctor. If you already have a tree nut allergy or any other food allergy, your doctor will be able to determine which specific allergens you should avoid.

Health Benefits Of Peanuts

Peanuts are just as healthy as their tree nuts counterparts in terms of storing high nutrients, vitamins, and fibers.

If you don't have a peanut allergy, you are in for a healthy balanced peanut diet! Peanuts are known for being heart-friendly with their unsaturated fat content. They also help to prevent heart disease by lowering the cholesterol level. Peanuts are protein-rich and can act as a great weight-loss snack.

And did you know? Studies show that people who eat nuts have a longer lifespan!

Here at Kidadl, we have carefully created lots of interesting family-friendly factsfor everyone to enjoy! If you liked this article about whether a peanut is a legume,then why not take a look at can dogs have crunchy peanut butter, or are peanuts poisonous?

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Written by Oluniyi Akande

Doctorate specializing in Veterinary Medicine

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Oluniyi AkandeDoctorate specializing in Veterinary Medicine

With an accomplished background as a Veterinarian, SEO content writer, and public speaker, Oluniyi brings a wealth of skills and experience to his work. Holding a Doctor of Veterinary Medicine degree from the University of Ibadan, he provides exceptional consulting services to pet owners, animal farms, and agricultural establishments. Oluniyi's impressive writing career spans over five years, during which he has produced over 5000 high-quality short- and long-form pieces of content. His versatility shines through as he tackles a diverse array of topics, including pets, real estate, sports, games, technology, landscaping, healthcare, cosmetics, personal loans, debt management, construction, and agriculture.

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