Olive oil may help lower the risk of heart disease, according to preliminary research that also showed it was beneficial as a substitute for butter or mayonnaise.
“Previous studies have linked high consumption of olive oil with better cardiovascular health, particularly in Mediterranean countries where olive oil intake is much higher than in the United States,” lead study author Marta Guasch-Ferre said in a news release.
“Our aim was to investigate whether higher olive oil consumption was beneficial to heart health in the U.S. population,” said Guasch-Ferre, a research scientist in the department of nutrition at Harvard T.H. Chan School of Public Health in Boston.
The study, presented Thursday at the American Heart Association’s Epidemiology and Prevention/Lifestyle and Cardiometabolic Health Scientific Sessions, examined 63,867 women and 35,512 men from 1990 to 2014. All participants were free of cancer, heart disease and other chronic diseases at the start of the study. Every four years, they answered questionnaires about their diet and lifestyle.
Researchers found those who ate more than half a tablespoon of olive oil each day had a 15% lower risk of having any kind of cardiovascular disease and a 21% lower risk of coronary heart disease. Replacing one teaspoon of butter, margarine, mayonnaise or dairy fat with the same amount of olive oil lowered the risk of cardiovascular disease by 5% and coronary heart disease by 7%. However, consuming more olive oil didn’t impact stroke risk.
Although olive oil proved to be healthier than butter and margarine, it did not present more benefits than other plant oils like corn, canola, safflower and soybean.
“One interesting thing our study shows is that although olive oil was better than most animal fats and margarine, it was not superior to vegetable oils in this study population,” Guasch-Ferre said. “This means that replacing any type of animal fat with vegetable oils, including olive oil but also others, could be a good strategy to improve cardiovascular health.”
The findings were observational, which means they don’t prove cause-and-effect. However, small intervention studies have found replacing animal fats with olive oil has a beneficial effect on fat levels in the blood.
“Future research is needed to investigate the mechanisms behind this association as well as the effects of other vegetable oils on heart health”Marta Guasch-Ferre
The results, also published in the Journal of the American College of Cardiology, provide further reason to incorporate more plant-based foods into our daily diets, said nutrition expert Penny Kris-Etherton.
“Using vegetable oils in cooking and in salads makes good sense,” Kris-Etherton said in a news release. She is a distinguished professor of nutrition at Pennsylvania State University and chair of the AHA’s Lifestyle and Cardiometabolic Health Council. “Research has overwhelmingly found that diets that are rich in plant-based foods, including healthier vegetable oils such as olive, safflower, corn and many others, can significantly benefit heart health,” she said.
Olive Oil Consumption and Cardiovascular Risk in U.S. Adults
Olive oil intake has been associated with lower risk of cardiovascular disease (CVD) in Mediterranean populations, but little is known about these associations in the U.S population.
This study sought to examine whether olive oil intake is associated with total CVD, coronary heart disease (CHD), and stroke risk.
This study included 61,181 women from the Nurses’ Health Study (1990 to 2014) and 31,797 men from the Health Professionals Follow-up Study (1990 to 2014) who were free of cancer, heart disease, and stroke at baseline. Diet was assessed using food frequency questionnaires at baseline and then every 4 years. Cox proportional hazards regressions were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).
During 24 years of follow-up, this study documented 9,797 incident cases of CVD, including 6,034 CHD cases and 3,802 stroke cases. After adjusting for major diet and lifestyle factors, compared with nonconsumers, those with higher olive oil intake (>0.5 tablespoon/day or >7 g/day) had 14% lower risk of CVD (pooled HR: 0.86; 95% CI: 0.79 to 0.94) and 18% lower risk of CHD (pooled HR: 0.82; 95% CI: 0.73 to 0.91). No significant associations were observed for total or ischemic stroke. Replacing 5 g/day of margarine, butter, mayonnaise, or dairy fat with the equivalent amount of olive oil was associated with 5% to 7% lower risk of total CVD and CHD. No significant associations were observed when olive oil was compared with other plant oils combined. In a subset of participants, higher olive oil intake was associated with lower levels of circulating inflammatory biomarkers and a better lipid profile.
Higher olive oil intake was associated with lower risk of CHD and total CVD in 2 large prospective cohorts of U.S. men and women. The substitution of margarine, butter, mayonnaise, and dairy fat with olive oil could lead to lower risk of CHD and CVD.
Cardiovascular disease; coronary heart disease; olive oil; plant oils; stroke.