Researchers tested whether extra virgin olive oil could help protect joints in rats with arthritis. They found that rats fed extra virgin olive oil had less damage to their joint cartilage, less inflammation, and their bodies produced more natural protective substances. The oil appeared to reduce harmful molecules that damage joints and increased the body’s ability to fight damage. While these results are promising, this was a rat study, so scientists will need to test whether the same benefits work in people before recommending it as a treatment.

The Quick Take

  • What they studied: Whether eating extra virgin olive oil could reduce joint damage and inflammation in rats with arthritis
  • Who participated: 21 male laboratory rats divided into three groups: healthy rats, rats with arthritis, and rats with arthritis that ate extra virgin olive oil
  • Key finding: Rats that ate extra virgin olive oil had significantly less joint damage, less inflammation, and higher levels of natural protective substances in their bodies compared to rats with untreated arthritis
  • What it means for you: This suggests extra virgin olive oil might help protect joints in people with arthritis, but this is early-stage research. More studies in humans are needed before doctors can recommend it as a treatment. It may be worth discussing with your doctor if you have arthritis.

The Research Details

Scientists created arthritis in rats by injecting a harmful chemical into their joints. They then divided the rats into three groups: one group stayed healthy as a comparison, one group had arthritis but ate normal food, and one group had arthritis but ate food mixed with extra virgin olive oil for 21 days. The researchers then examined the rats’ joints under microscopes, tested their blood for harmful and protective substances, and took X-rays to see the damage.

This type of study is called a ‘preclinical’ or ‘animal model’ study. Scientists use it to test whether something might work before trying it in humans. The researchers used multiple ways to measure the effects—looking at the joints directly, checking for inflammation, measuring harmful molecules, and testing the body’s natural defenses.

The study was designed to test whether olive oil’s known antioxidant properties (its ability to fight cellular damage) could help protect joints from arthritis damage.

This research approach matters because it allows scientists to carefully control all the conditions and measure exactly what happens. In rats, researchers can examine joint tissue directly and measure specific harmful molecules that would be harder to study in people. The findings suggest a possible mechanism for how olive oil might help, which could guide future human studies.

This study was published in a peer-reviewed medical journal, meaning other experts reviewed it before publication. The sample size was small (21 rats), which is typical for early animal studies but means results should be confirmed in larger studies. The researchers used multiple measurement methods (microscopy, blood tests, imaging), which strengthens confidence in the findings. However, because this is an animal study, results may not directly apply to humans.

What the Results Show

Rats that ate extra virgin olive oil showed significantly less damage to their joint cartilage compared to rats with untreated arthritis. When researchers examined the joints under a microscope, the olive oil group had better preservation of proteoglycans—the substances that give cartilage its cushioning ability. The inflammation in the joint lining (synovitis) was also reduced in the olive oil group.

The most important finding was about oxidative stress, which is cellular damage caused by harmful molecules. Rats fed olive oil had significantly lower levels of oxidized LDL (a particularly damaging form of cholesterol) and other stress markers. At the same time, their bodies produced more antioxidants—natural protective substances that fight this damage. The researchers found a strong connection between oxidized LDL levels and overall oxidative stress, suggesting these measurements are related.

Another key finding was that fewer joint cells (chondrocytes) were dying in the olive oil group. Arthritis causes these cells to die, which leads to cartilage breakdown. The olive oil appeared to protect these cells from dying.

The study found that the protective effects of olive oil were measurable across multiple systems in the body. The antioxidant capacity (the body’s ability to fight damage) was significantly higher in the olive oil group. This suggests olive oil doesn’t just work in one way—it appears to activate the body’s natural defense systems while also reducing harmful molecules.

Previous research has shown that extra virgin olive oil contains compounds with antioxidant properties, and other studies have suggested these compounds might help with inflammation. This study is one of the first to specifically test whether olive oil can protect joints in arthritis. The findings align with what scientists expected based on olive oil’s known properties, but this is the first direct evidence in an arthritis model.

This study was conducted in rats, not humans, so the results may not work the same way in people. The sample size was small (21 rats total), which is typical for animal studies but means results need confirmation. The study only lasted 21 days, so we don’t know if the benefits continue longer or if they’re permanent. The study didn’t test different doses of olive oil or compare it to other treatments. Finally, we don’t know exactly which compounds in the olive oil were responsible for the benefits.

The Bottom Line

Based on this research, extra virgin olive oil shows promise as a potential helper for arthritis, but it’s too early to recommend it as a treatment. The evidence is moderate quality because it’s from animal studies. If you have arthritis, it’s reasonable to include extra virgin olive oil in your diet as part of a healthy eating pattern, but don’t rely on it as your only treatment. Always discuss any dietary changes or supplements with your doctor, especially if you’re taking arthritis medications.

People with arthritis or at risk for arthritis might be interested in this research. However, this study doesn’t yet prove that olive oil will help people—only that it helped rats. People taking blood thinners should check with their doctor before significantly increasing olive oil intake. This research is most relevant to people looking for ways to support their joint health through diet.

In the rat study, benefits appeared within 21 days. If similar effects occur in humans, you might expect to see benefits within a few weeks to a few months, but this is speculation. More human studies are needed to establish realistic timelines. Don’t expect olive oil to replace prescribed arthritis medications.

Want to Apply This Research?

  • Track daily olive oil intake (in tablespoons) and joint pain or stiffness levels on a scale of 1-10. Record this daily for at least 8-12 weeks to see if there’s a pattern between increased olive oil consumption and changes in joint symptoms.
  • Add 1-2 tablespoons of extra virgin olive oil to your daily diet through salad dressings, drizzling on cooked vegetables, or dipping bread. Start with a small amount and gradually increase to see how your body responds. Track this consistently in your app.
  • Create a weekly summary that shows your average joint pain/stiffness score and average daily olive oil intake. Look for trends over 8-12 weeks. Also note other factors that might affect joints (exercise, other foods, stress) to get a complete picture of what might be helping.

This research was conducted in rats and has not been tested in humans. Extra virgin olive oil should not be used as a replacement for prescribed arthritis medications or medical treatment. Always consult with your healthcare provider before making significant dietary changes or starting any supplement, especially if you take blood thinners or have other medical conditions. Individual results may vary, and what works in animals may not work the same way in people. This information is for educational purposes only and should not be considered medical advice.