Which nut is a cashew? Debunking the Myth of the Cashew Nut

December 13, 2025 •

3 min read

According to botanical definitions, the cashew, scientifically known as Anacardium occidentale, is not a true nut but is instead a seed that develops inside a drupe. Its intriguing growth process and complex structure often lead to confusion, as it is widely accepted as a culinary nut and grouped with others in stores. This article delves into the truth of which nut is a cashew and explores its unique place in the plant kingdom.

Quick Summary

This article explains the botanical classification of the cashew, revealing it is a seed from a drupe and not a true nut. It details the unusual way cashews grow and clarifies the difference between culinary and botanical definitions of 'nut.'

Key Points

Botanically Not a Nut: Despite being called a nut, the cashew is a seed that grows inside a drupe, which is a type of fleshy fruit.
Seed Grows Outside the Fruit: The cashew seed develops outside and at the bottom of the cashew apple, which is a swollen stem and not the true fruit.
Not a Legume: Unlike peanuts, cashews are not legumes; they grow on trees and belong to the family that includes mangoes and pistachios.
Requires Special Processing: The cashew's hard shell contains a toxic oil, urushiol, which requires careful roasting or steaming before the kernel can be safely consumed.
Nutritionally Rich: Cashews are a great source of healthy fats, protein, vitamins, and minerals, providing benefits for heart, bone, and immune health.
A Culinary All-Star: Due to its mild flavor and creamy texture, the cashew is a versatile ingredient used in snacks, stir-fries, and as a dairy-free base for creams and cheeses.

What Exactly is a Cashew? The Botanical Truth

From a botanical standpoint, the cashew you eat is the seed of the cashew tree (Anacardium occidentale), a tropical evergreen native to Brazil. The edible cashew kernel is encased within a tough, double-hulled shell that hangs from the bottom of a larger, pear-shaped fleshy structure known as the cashew apple. This means the cashew is technically a drupe seed, a classification it shares with almonds, pistachios, and peaches.

The Fascinating Anatomy of the Cashew Fruit

The cashew fruit is a marvel of nature. The most prominent feature is the brightly colored cashew apple, a swollen stem or pedicel, which is edible but highly perishable and rarely seen outside of tropical regions. Below this false fruit, the true fruit—a kidney-shaped drupe—develops. Inside the hard shell of this drupe lies the single seed we consume. The two layers of the shell contain a caustic, allergenic oil called urushiol, the same substance found in poison ivy. This is why you will never find unshelled cashews for sale; they must be carefully processed through roasting or steaming to neutralize the toxic oil.

Cashew vs. Legume: Clearing Up Another Misconception

Another common question is whether cashews are legumes, often fueled by their culinary association with the groundnut (peanut), which is a legume. The answer is a definitive no. Legumes grow in pods containing multiple seeds and are not found on trees. Cashews, however, grow on trees and are classified in the Anacardiaceae family, a botanical group that also includes mangoes and pistachios. Their distinct growth pattern and family lineage separate them from the legume category.

The Culinary vs. Botanical Distinction

The confusion surrounding the cashew's identity stems from the difference between botanical and culinary classifications. In the kitchen and at the grocery store, the term "nut" is used much more loosely. It refers to any number of edible seeds that are often roasted and used in cooking, regardless of their scientific origin.


Comparison Table: Culinary Nut vs. Botanical Reality	Common Name	Culinary Classification	Botanical Classification	Key Distinction
Cashew	Tree Nut	Drupe Seed	Seed grows outside the false fruit (cashew apple) in a drupe.
Almond	Tree Nut	Drupe Seed	The kernel is the seed inside a fleshy drupe, like a peach.
Walnut	Tree Nut	Drupe Seed	The edible part is the seed of a drupe.
Pistachio	Tree Nut	Drupe Seed	Similar to almonds and cashews, it's the seed of a drupe.
Hazelnut	Tree Nut	True Nut	A true botanical nut with a hard shell enclosing the seed.
Peanut	Nut	Legume	Grows underground in a pod and is a member of the bean family.

From a Nutritional Standpoint: The Benefits of a “Nut”

Despite its botanical identity, the cashew is nutritionally aligned with other tree nuts. Cashews are packed with heart-healthy monounsaturated fats, protein, and essential minerals like copper, magnesium, and zinc. Their rich nutritional profile offers numerous health benefits, regardless of their official classification. The creamy, sweet flavor and satisfying texture make them a popular choice for snacking, cooking, and creating dairy alternatives like cashew milk and vegan cheese.

Conclusion

So, which nut is a cashew? Botanically speaking, it's not a nut at all, but a drupe seed. Culturally and culinarily, however, it is firmly established as a tree nut, enjoyed and utilized in countless ways around the world. The journey of the cashew from a toxic-shelled seed dangling from a cashew apple in Brazil to the buttery, delicious snack in your pantry is a testament to its unique and complex nature. Understanding this distinction enriches our appreciation for this fascinating food, highlighting the difference between scientific classification and everyday use. For those with nut allergies, it is critical to remember that cashews are still classified as tree nuts for safety purposes due to cross-reactivity. For everyone else, it’s simply a new and interesting fact to ponder the next time you enjoy a handful of this delightful “nut.” To learn more about the cashew's origins and processing, explore the resources from Cashew Coast.

Frequently Asked Questions

A cashew is neither a true nut nor a legume. Botanically, it is classified as a drupe seed, and it grows on a tree, distinguishing it from legumes like peanuts, which grow in pods.

The cashew is referred to as a nut for culinary purposes, based on its shared nutritional profile and texture with other tree nuts. This is a common linguistic and cultural classification that differs from its scientific botanical definition.

The cashew apple is a pear-shaped, fleshy structure that develops from the stem of the cashew flower. It is an 'accessory fruit' or 'false fruit' that grows above the true fruit, which contains the cashew seed.

No, the 'raw' cashews you buy in stores are not truly raw. To make them safe for consumption, they must be heated (steamed or roasted) during processing to remove a toxic substance in their shell.

You cannot buy cashews in the shell because the shell contains a caustic, irritating oil called urushiol, which is related to the oil found in poison ivy. The toxic oil must be neutralized before the kernel can be safely handled and eaten.

Yes, cashews are very good for you. They are rich in heart-healthy monounsaturated fats, protein, and essential minerals like copper and magnesium. These nutrients support heart health, bone strength, and the immune system.

Yes, there is a possibility of cross-allergy between cashews and pistachios because they belong to the same botanical family, Anacardiaceae. People with one allergy should be cautious with the other, though a reaction is not guaranteed.