Drinking a small amount of olive oil each day, typically one to two tablespoons, delivers a concentrated dose of heart-healthy fats, anti-inflammatory compounds, and fat-soluble vitamins that support everything from blood pressure to blood sugar control. A single tablespoon contains about 119 calories and is roughly 73% oleic acid, a monounsaturated fat responsible for many of olive oil’s measurable health effects. Here’s what actually happens in your body when you drink it.
Blood Pressure and Heart Health
Oleic acid, the primary fat in olive oil, has a direct effect on blood pressure. In animal studies published in the Proceedings of the National Academy of Sciences, daily oleic acid intake lowered systolic blood pressure by about 17 mmHg over two weeks. In hypertensive subjects, the reductions were even more pronounced, reaching 26 mmHg. The mechanism involves changes in cell membrane composition that influence how blood vessels regulate pressure through signaling pathways.
Beyond blood pressure, diets rich in olive oil consistently improve the ratio of HDL (“good”) to LDL (“bad”) cholesterol. Because drinking olive oil delivers these fats without the added sodium or sugars that often accompany them in cooked dishes, some people prefer it as a straightforward way to get the dose that drives these cardiovascular effects.
A Natural Anti-Inflammatory Compound
Fresh, high-quality extra virgin olive oil contains a compound called oleocanthal that inhibits the same inflammation-producing enzymes targeted by ibuprofen. You may have noticed the peppery, throat-catching sensation when tasting good olive oil. That sting is oleocanthal at work. The stronger the sting, the higher the concentration.
Oleocanthal is only present in meaningful amounts in cold-pressed extra virgin olive oil that has been properly harvested and stored. Refined or light olive oils lose most of this compound during processing. If you’re drinking olive oil specifically for its anti-inflammatory benefits, the quality and freshness of the oil matter more than the quantity. Studies suggest that one to two tablespoons per day of extra virgin olive oil can reduce C-reactive protein, a key marker of systemic inflammation.
Blood Sugar Control After Meals
One of the more practical benefits of drinking olive oil shows up in how your body handles sugar after eating. In a clinical crossover study of patients with impaired fasting glucose, adding just 10 grams (about two teaspoons) of extra virgin olive oil to a meal significantly reduced the post-meal blood sugar spike compared to eating the same meal without it. Insulin response improved, and the gut hormone GLP-1, which helps regulate blood sugar and slows digestion, increased substantially.
GLP-1 does more than manage glucose. It enhances satiety by signaling to your brain that you’ve eaten enough, and it slows gastric emptying so nutrients are absorbed more gradually. Diets rich in monounsaturated fats like oleic acid appear to boost GLP-1 secretion, which may partly explain why people on Mediterranean-style diets tend to have better blood sugar profiles and report feeling more satisfied after meals.
Digestive Effects
Olive oil acts as a mild lubricant in the digestive tract, softening stool and easing its passage. This is the same basic mechanism behind mineral oil laxatives, but with the added benefit of being a natural food with its own nutritional value. In studies on constipation, starting doses as low as 4 milliliters per day (less than a teaspoon) were enough to produce a laxative effect. For people dealing with occasional constipation, a tablespoon of olive oil on an empty stomach is a common folk remedy that has some clinical backing.
That said, drinking too much olive oil at once can cause nausea, cramping, or diarrhea, especially if your body isn’t used to consuming concentrated fat. Starting with a smaller amount and gradually increasing is a practical approach.
Gut Bacteria and Polyphenols
Extra virgin olive oil is rich in polyphenols, plant compounds that act as prebiotics in the gut. Research published in Frontiers in Nutrition found that olive oil polyphenols modulate which bacterial strains thrive in the intestine. In mice fed diets enriched with extra virgin olive oil, the strains that flourished carried fewer antibiotic resistance genes and fewer virulence factors, essentially selecting for more beneficial versions of gut bacteria. This is a different mechanism than simply “adding” good bacteria. The polyphenols reshape the existing bacterial community toward a healthier profile.
Drinking It Straight vs. With Food
If you’re drinking olive oil for its polyphenol content, the delivery method matters. Research on hydroxytyrosol, one of olive oil’s key polyphenols, found that absorption was actually lower when consumed in an oily matrix compared to a water-based supplement. Polyphenol metabolites were harder to detect in blood plasma after consuming fortified olive oil than after taking the same compounds in aqueous form. This suggests that while drinking olive oil delivers fats and fat-soluble vitamins efficiently, the polyphenols may absorb better when olive oil is consumed alongside water-rich foods like salads or vegetables rather than on its own.
Fat-soluble vitamins, on the other hand, absorb well in oil. Each tablespoon of olive oil provides about 1.94 mg of vitamin E (roughly 13% of the daily value) and 8.13 micrograms of vitamin K, which plays a role in blood clotting and bone metabolism.
How Much Is Too Much
At 119 calories per tablespoon, olive oil adds up quickly. Two tablespoons per day contributes nearly 240 calories, which is meaningful if you’re not adjusting the rest of your diet to compensate. Most of the studied health benefits appear at doses of one to two tablespoons daily. Going significantly beyond that doesn’t appear to amplify the benefits and simply adds calories.
Research on cognitive health has found that people consuming more than half a tablespoon per day tend to have lower rates of Alzheimer’s disease, which suggests the threshold for some protective effects is relatively modest. You don’t need to drink a quarter cup each morning. A consistent, moderate intake is what the evidence supports. If the taste of straight olive oil doesn’t appeal to you, drizzling it over food delivers the same compounds with better polyphenol absorption and a more enjoyable experience.