What's the Difference Between Peas and Soybeans? A Complete Guide

December 20, 2025 •

3 min read

According to the Food and Agriculture Organization of the United Nations, soybeans are one of the world's most economically important crops, while peas are a highly water-efficient crop. For those navigating plant-based diets or simply curious about their food, understanding what's the difference between peas and soybeans can be crucial.

Quick Summary

This article explores the core distinctions between peas and soybeans, detailing their nutritional profiles, plant characteristics, culinary applications, and processing methods.

Key Points

Botanical Origin: Peas are typically a cool-weather crop with tendrils, while soybeans prefer warmer climates and have solid, twining stems.
Allergen Profile: Soy protein is a common allergen, while pea protein is hypoallergenic, making it a safer option for many with sensitivities.
Protein Quality and Absorption: Soy protein has a higher protein digestibility score (PDCAAS of 1), while pea protein is notable for its high concentration of BCAAs like leucine and arginine.
Environmental Impact: Peas are more water-efficient and fix nitrogen in the soil, reducing the need for artificial fertilizers, whereas soybeans are widely cultivated and sometimes genetically modified.
Culinary Applications: Peas are often eaten fresh or frozen, while soybeans are commonly processed into products like tofu, soy milk, and tempeh.
Health Benefits: Soybeans contain phytoestrogens linked to potential cardiovascular benefits, while pea protein's amino acid profile supports muscle growth and recovery.

Botanical and Growth Differences

While both peas and soybeans belong to the legume family, they have distinct botanical characteristics and growing habits. Peas (Pisum sativum) are typically a cooler-weather crop with hollow stems and grow with tendrils that grasp onto supports. Soybeans (Glycine max), on the other hand, are a warm-weather crop with solid, hairy stems that twine around trellises. Their temperature preferences mean they are cultivated in different seasons and climates, influencing their agricultural impact. Additionally, soybeans exhibit higher insect feeding tolerance compared to peas.

Agricultural and Environmental Impact

Soybeans are a globally dominant crop, extensively cultivated for oil and high-protein meal. This large-scale production often involves genetically modified varieties, particularly for herbicide resistance. Peas, however, are a highly water-efficient crop and, unlike many soybeans, naturally fix nitrogen into the soil, which can reduce the need for synthetic nitrogen fertilizers and improve soil health.

A Nutritional Deep Dive

Nutritionally, both legumes are protein powerhouses, but their profiles contain key differences. Soy protein is considered a complete protein, containing all nine essential amino acids. However, the presence of phytic acid can inhibit nutrient absorption. Pea protein is also a complete protein when isolated, containing all nine essential amino acids, although it is slightly lower in methionine. Pea protein is also hypoallergenic, making it a suitable alternative for those with soy allergies.

Key Macronutrient and Micronutrient Differences


Feature	Peas	Soybeans
Protein Content	Rich in protein, especially in concentrated isolate form.	Excellent protein source, often slightly higher protein per scoop in powders.
Amino Acids	Contains all nine essential amino acids; slightly lower in methionine.	Contains all nine essential amino acids; high in L-Glutamine.
Fats	Very low in fat.	Generally low in fat, though slightly more than peas.
Carbohydrates	Contain large amounts of carbohydrates.	Moderate carbohydrate content.
Isoflavones	Not a significant source.	Contains phytoestrogens (isoflavones), which are compounds with a hormone-like structure.
Allergens	Hypoallergenic and a safe choice for many.	A common allergen, especially for infants and children.
Digestibility	Good digestibility, with pea protein isolate scoring high on the PDCAAS scale.	High digestibility, with a top PDCAAS score of 1.

Culinary Applications and Processing

The culinary uses for peas and soybeans are diverse and distinct, reflecting their different compositions and flavor profiles.

Peas in the Kitchen

Peas are known for their sweet, mild flavor and are often used in whole-form applications, both fresh and frozen. They can be the star of a dish or a bright complement to other ingredients. Common uses include:

Snackable: English peas and snap peas can be eaten raw.
Soups and Stews: Green peas add flavor and color to dishes like shepherd's pie and pea soup.
Protein Powder: Processed into hypoallergenic pea protein isolate, used in plant-based powders and supplements.

Soybeans in the Kitchen

Soybeans have a more robust, earthy flavor and are versatile, with many processed forms being staples in various cuisines worldwide. Raw soybeans contain anti-nutritional factors and are typically cooked or processed. Examples include:

Edamame: Fresh, steamed soybeans eaten from the pod.
Tofu and Tempeh: Created by coagulating soy milk or fermenting soybeans.
Soy Milk: A popular dairy alternative.
Soy Sauce: A fermented condiment.
Meat Substitutes: A common ingredient in many vegetarian and vegan meat alternatives.

Conclusion

While peas and soybeans share a common legume family heritage and high-protein content, their differences are significant. From their growing seasons and plant characteristics to their varied nutritional profiles and culinary uses, each offers unique benefits. Soybeans provide a complete protein source rich in isoflavones, though they are also a common allergen. Peas are hypoallergenic, water-efficient, and have a more neutral flavor. Whether a culinary choice or a dietary requirement, understanding these distinctions helps to make an informed decision when comparing peas and soybeans.

The Difference in a Nutshell

Peas are a cool-weather crop with delicate, tendriled vines, while soybeans are a warm-weather crop with sturdier, twining stems.
Soy protein has a top digestibility score, but some individuals are allergic to it.
Pea protein is hypoallergenic and excels in amino acids like arginine, making it excellent for muscle synthesis.
Soybeans often come from genetically modified crops, whereas peas are typically non-GMO.
In cooking, peas are often used fresh or frozen, whereas soybeans are a base for a wider range of processed products like tofu, soy milk, and fermented sauces.
Peas improve soil health by fixing nitrogen, a valuable agricultural trait.

Frequently Asked Questions

The 'better' choice depends on individual needs. Pea protein is hypoallergenic and contains high levels of BCAAs like arginine, which is excellent for muscle building. Soy protein has a higher digestibility score and is a complete protein, though it is a common allergen.

Peas are typically used fresh, frozen, or in protein powders, often prized for their sweet, mild flavor. Soybeans are commonly processed into staples like tofu, tempeh, and soy milk, and have a more robust, earthy flavor.

Yes, both peas and soybeans are members of the legume family, which also includes peanuts, lentils, and other beans.

Yes, they differ significantly. Peas are a cool-weather crop, thriving in cooler temperatures, whereas soybeans are a warm-weather crop that is sensitive to frost.

While both are high-protein sources, some sources suggest soy protein powder has a slightly higher protein content per serving compared to pea protein powder. However, both are potent protein powerhouses.

Peas are known for being more water-efficient and naturally improving soil quality by fixing nitrogen. Many soybeans are genetically modified, which is a key environmental distinction.

Yes, soy is a common food allergen, especially in babies and young children, whereas pea protein is generally considered hypoallergenic.