Olive oil is predominantly a monounsaturated fat. Its primary fatty acid, oleic acid, makes up 55% to 83% of the oil depending on the olive variety, growing conditions, and processing method. This makes olive oil one of the richest common cooking oils in monounsaturated fat, which is the same type of fat found in avocados and most nuts.
The Full Fat Breakdown
While olive oil is known for its monounsaturated fat, it actually contains all three major types of dietary fat in different proportions. Oleic acid dominates, but the remaining fats play a role too.
Monounsaturated fat accounts for roughly 55% to 83% of olive oil’s fatty acid content. Oleic acid is the main one, with small amounts of other monounsaturated fats present. A single tablespoon of olive oil delivers about 10 grams of monounsaturated fat.
Saturated fat makes up about 8% to 25% of the oil, mostly from palmitic acid (7.5% to 20%) and stearic acid (0.5% to 5%). This is a relatively low proportion compared to butter or coconut oil, which are majority saturated fat. One tablespoon contains roughly 2 grams of saturated fat.
Polyunsaturated fat is the smallest fraction, with linoleic acid (an omega-6 fat) ranging from 3.5% to 21% and linolenic acid (an omega-3 fat) at 1.5% or less. This comes out to about 1.5 grams per tablespoon.
The wide ranges exist because olive variety matters a great deal. Research on different cultivars found oleic acid content ranging from about 66% in some Greek varieties to over 75% in others, just based on the type of olive used.
Why Monounsaturated Fat Matters
The high oleic acid content gives olive oil two practical advantages: health benefits and stability. Because oleic acid has only one double bond in its molecular structure, it resists oxidation far better than the polyunsaturated fats found in soybean or corn oil. In lab comparisons, olive oil deteriorated significantly less than both corn and soybean oils when exposed to the same conditions of air, light, and deep frying. This means olive oil holds up better in your pantry and in your pan.
On the health side, the evidence is strong. The PREDIMED trial, one of the largest dietary studies ever conducted, enrolled 7,447 adults at high cardiovascular risk and found that a Mediterranean diet supplemented with about 4 tablespoons of extra virgin olive oil per day reduced the combined risk of heart attack, stroke, and cardiovascular death by roughly 30% compared to a low-fat diet. A separate large study with long-term follow-up found that people consuming more than half a tablespoon of olive oil daily had 19% lower risk of dying from any cause and 29% lower risk of dying from neurodegenerative disease, compared to people who rarely consumed olive oil.
The American Heart Association’s 2026 dietary guidance recommends nontropical plant oils like olive oil as replacements for animal fats and tropical oils in food preparation, specifically because of their high unsaturated fat content.
Extra Virgin vs. Refined: Same Fat, Different Extras
All grades of olive oil share essentially the same fatty acid profile. Whether you buy extra virgin, virgin, or refined olive oil, you’re getting the same proportions of monounsaturated, polyunsaturated, and saturated fat. The differences lie in what comes along with those fats.
Extra virgin olive oil retains far more protective plant compounds. One study found that extra virgin oils contained 19 to 53 mg/kg of phenolic compounds, while refined oils contained just 2 to 5 mg/kg. That’s roughly 10 times the concentration. These compounds are what give good extra virgin olive oil its peppery bite and bitter notes. One of them, oleocanthal, produces that distinctive throat-tingling sensation and has anti-inflammatory effects that researchers have compared to ibuprofen. Another, hydroxytyrosol, is one of the most potent antioxidants found in any food.
Extra virgin olive oil also contains significantly more squalene, a compound with its own antioxidant properties. In testing, extra virgin oils held 213 to 459 mg per 100 grams of squalene, while refined olive oils contained 66 to 119 mg per 100 grams. These phenolic compounds also help protect the oil itself from going rancid by neutralizing free radicals and slowing oxidation.
One tablespoon of olive oil provides about 1.9 mg of vitamin E, which adds to the oil’s antioxidant profile.
Cooking With Olive Oil
Olive oil’s monounsaturated fat profile makes it more heat-stable than oils rich in polyunsaturated fats. High-quality extra virgin olive oil with low acidity has a smoke point around 207°C (405°F), while refined olive oil can tolerate even higher temperatures, reaching 199 to 243°C (390 to 470°F). Both are well above the temperatures used in typical home cooking, including sautéing and roasting.
Storage matters more than most people realize. Prolonged exposure to air and light triggers oxidative deterioration even at room temperature. Olive oil resists this better than polyunsaturated oils, but you’ll preserve its quality and beneficial compounds by storing it in a dark glass bottle, away from the stove, and using it within a few months of opening.
How Olive Oil Compares to Other Cooking Fats
- Butter: About 63% saturated fat, 26% monounsaturated. Nearly the inverse of olive oil’s ratio.
- Coconut oil: About 82% saturated fat. Very little monounsaturated or polyunsaturated fat.
- Canola oil: About 63% monounsaturated, closer to olive oil, but with more polyunsaturated fat and far fewer phenolic compounds.
- Soybean oil: Majority polyunsaturated fat, which makes it less oxidatively stable than olive oil under heat and light exposure.
Olive oil occupies a useful middle ground: high in the monounsaturated fat linked to cardiovascular benefits, naturally resistant to oxidation, and, in its extra virgin form, packed with bioactive compounds that no refined oil can match.