Peanut oil sits in a gray area. Peanuts are botanically legumes, not seeds in the way that sunflower, canola, or soybean plants produce seeds. But the food industry routinely groups peanut oil with seed oils because of how it’s produced, what it’s made of, and how it behaves in cooking. Whether you call it a seed oil depends on whether you’re using a botanical definition or a practical one.
Peanuts Are Legumes, Not Seeds
Despite the name, a peanut is not a nut. It’s a legume, belonging to the same plant family as soybeans, lentils, and chickpeas. Like other legumes, peanuts are edible seeds that grow in pods, but unlike most legumes, they develop underground rather than on vines or shrubs. Botanically, this places the peanut in a completely different category from the plants that produce what most people think of as “seed oils,” such as sunflower seeds, rapeseed (canola), safflower seeds, or cottonseed.
So in the strictest botanical sense, peanut oil is a legume oil, not a seed oil.
Why the Industry Treats It as a Seed Oil
Botanical classification and food industry classification don’t always line up. Oklahoma State University’s food science extension notes that peanuts are “generally included amongst the oilseeds because of their high oil content.” The extraction process mirrors what’s used for other oilseeds: mechanical pressing followed by solvent extraction (typically hexane) to pull out remaining oil from the press cake. Refined peanut oil, cold-pressed peanut oil, and solvent-extracted peanut oil all end up with similar fatty acid profiles.
The USDA and most trade organizations lump peanut oil in with other vegetable oils. If someone is avoiding “seed oils” because of how they’re industrially processed, peanut oil is produced the same way.
How Its Fat Profile Compares to Seed Oils
The reason many people search this question is the ongoing conversation about omega-6 fats and seed oils. Here’s where peanut oil lands relative to common seed oils.
Peanut oil’s dominant fat is oleic acid, a monounsaturated fat (the same one abundant in olive oil). Across different peanut varieties, oleic acid makes up roughly 36% to 54% of the oil, sometimes reaching as high as 67% in certain cultivars. Linoleic acid, the omega-6 polyunsaturated fat that drives most of the seed oil debate, typically accounts for 25% to 41% of peanut oil depending on the variety and growing region.
For comparison, soybean oil contains about 50% to 55% linoleic acid, sunflower oil around 60% to 70% (in standard varieties), and corn oil roughly 55%. Peanut oil’s linoleic acid content is meaningfully lower than these common seed oils but still substantial. It’s closer to canola oil’s range. Saturated fat in peanut oil runs about 11% to 13%, mostly from palmitic acid, which is comparable to most other vegetable oils.
The combined unsaturated fat content (oleic plus linoleic) accounts for 74% to 81% of peanut oil’s total fatty acids. That high unsaturated proportion is typical of seed oils as a group.
Refined vs. Unrefined Peanut Oil
Refined peanut oil and unrefined (cold-pressed or roasted) peanut oil differ in ways that matter for cooking and for people with peanut allergies.
Refined peanut oil has a smoke point of about 450°F (232°C), making it one of the more heat-stable cooking oils available. That high smoke point is why it’s a staple for deep frying, especially in restaurant kitchens. Unrefined peanut oil has a much lower smoke point of 320 to 350°F (160 to 177°C) and a stronger peanut flavor, which makes it better suited for dressings or light sautéing.
On the allergy front, refining strips out nearly all peanut protein. Research published in Clinical and Translational Allergy estimated that highly refined peanut oil poses a risk of objective allergic reactions in only 0.03% to 0.6% of peanut-allergic consumers, with protein concentrations falling below the detection limits of current analytical methods. Cold-pressed or gourmet peanut oils retain more protein and pose a higher risk for people with peanut allergies.
The Practical Answer
If your concern is botanical accuracy, peanut oil is not a seed oil. It comes from a legume. If your concern is industrial processing, fat composition, or the omega-6 content that fuels the “seed oil” debate, peanut oil shares enough characteristics with seed oils to belong in the conversation. Its omega-6 content is lower than soybean, corn, or sunflower oil, but it’s far from negligible. And the refining process is essentially identical.
Soybean oil, notably, is also a legume oil by the same botanical logic, yet it’s almost always included in lists of seed oils. The category “seed oil” as used in popular health discussions is really shorthand for industrially processed, high-omega-6 vegetable oils. By that informal definition, peanut oil qualifies, even if the plant it comes from technically isn’t a seed.