Extra Virgin Olive Oil vs. Refined Olive Oil: Which Is Better for Heart Health?
When it comes to heart health, olive oil often takes center stage. But does the type of olive oil—extra virgin (EVOO) or refined (ROO)—really make a difference? A recent study sought to answer this question by comparing the effects of these two oils on cholesterol and cardiovascular health markers. Here’s what they found.
What Was Studied?
Researchers in Japan conducted a study to see how EVOO and ROO affect LDL oxidation (a key factor in cardiovascular disease risk) and cholesterol levels, including LDL-C (“bad” cholesterol), HDL-C (“good” cholesterol), and triglycerides.
Who Participated?
The study involved 77 men aged 35 to 64 with elevated LDL cholesterol levels (averaging 126 mg/dL). None of them had a history of cardiovascular disease or were on dietary or medical treatments.
How Was the Study Conducted?
Participants consumed 14 grams of EVOO or ROO daily for three weeks, followed by a two-week break before switching oils. EVOO contained 5 mg of polyphenols, while ROO had only 0.3 mg. Polyphenols are natural compounds in olive oil that may protect against LDL oxidation.
What Were the Results?
There was no significant difference between the two oils in terms of their effects on LDL oxidation or cholesterol levels.
However, the study raised some important considerations:
- Polyphenol Content: EVOO generally has more polyphenols than ROO, which may explain its potential cardiovascular benefits.
- Dosage Matters: The 14 grams (about one tablespoon) used in the study might not be enough to see significant effects. Past research suggests that higher doses, around 25–60 mL per day, show more promising results.
- Dietary Context: The Japanese participants’ typical diets are lower in fat and higher in polyphenol-rich foods (like green tea) compared to Western diets. This could influence the results.
The Big Picture
Although this study didn’t find a clear advantage for EVOO over ROO, other research suggests that EVOO’s higher polyphenol content can:
- Reduce LDL oxidation.
- Lower LDL-C levels when replacing saturated fats like butter or lard.
- Improve other heart-health markers, such as blood pressure and inflammation.
For those looking to improve their heart health, choosing EVOO with a higher polyphenol content and incorporating it into a heart-healthy diet may be beneficial.
Anything Else to Know?
While this study adds to our understanding, it’s worth noting that four researchers were employees of the olive oil manufacturer. Additionally, the study’s small size and short duration highlight the need for more research, particularly in diverse populations.
Takeaway
EVOO and ROO may have similar effects in some scenarios, but the overall evidence suggests that EVOO, especially rich in polyphenols, has a stronger potential to support heart health. Aim to use EVOO as a replacement for less healthy fats like butter to get the most benefit.
Tsujino S, Sadamitsu S, Nosaka N, Fushimi T, Kishimoto Y, Kondo KAge-Related Effects of Olive Oil Polyphenol Ingestion on Oxidation of Low-Density Lipoprotein in Healthy Japanese Men: A Randomized Controlled Double-Blind Crossover Trial.Nutrients.(2024 Oct 1)
