Among the most commonly used are olive oil, canola oil, sunflower oil, soybean oil, and palm oil. Each has different characteristics in terms of flavor, smoke point, and nutritional benefits. Not all of them have the same benefits, which is why their consumption is not without controversy.
For example, palm oil has been criticized for its high saturated fat content and environmental impact, while some highly processed oils, such as soybean oil, have been questioned for their relationship to inflammation in the body.
When in doubt about which product is best for cooking, a new study conducted by researchers from Mass General Brigham, Harvard T.H. Chan School of Public Health, and the Broad Institute of MIT and Harvard in the United States shows that people who consume vegetable oil instead of butter may experience health benefits and even have a lower risk of premature death.
BUT OF ALL VEGETABLE OILS, WHICH ONE IS THE BEST?
The researchers examined diet and health data from 200,000 people followed for over 30 years and found that higher intake of vegetable oils, especially soybean, canola, and olive oil, was associated with lower overall mortality, cancer mortality, and cardiovascular disease mortality, while butter intake was associated with higher overall and cancer mortality risk.
The results are published in ‘JAMA Internal Medicine’ and presented simultaneously at the EPI/Lifestyle Scientific Sessions of the American Heart Association. «The surprising thing is the magnitude of the association we found: we saw a 17% lower risk of death when we modeled the switch from butter to vegetable oils in the daily diet. That is a significant effect on health,» said the study’s lead author, Yu Zhang, research assistant in the Channing Division of Network Medicine at Brigham and Women’s Hospital.
DIFFERENCES BETWEEN BUTTER AND VEGETABLE OILS
A key difference between butter and oil is the type of fatty acids they contain. Butter is rich in saturated fatty acids, while vegetable oils have more unsaturated fatty acids. While many studies have been conducted on dietary fatty acids, fewer studies have focused on their primary food sources, including butter and oils.
Many previous studies have analyzed an individual’s diet at a specific time and have been conducted in a small population, limiting their applicability to public health.
The new study analyzed dietary data from 221,054 participants in the Nurses’ Health Study (NHS), Nurses’ Health Study II (NHSII), and the Health Professionals Follow-up Study (HPFS). Every four years, they answered questions about the frequency of consuming certain types of foods. Researchers used the data to estimate the amount of butter and vegetable oils consumed.
The total intake of butter included butter from butter-margarine blends, spreadable butter added to foods and bread, and butter used for baking and frying at home. Vegetable oil intake was estimated based on reported use for frying, sautéing, baking, and dressing salads.
WHAT IS THE BEST OPTION FOR HEALTH?
The researchers also identified participants who had died and their causes of death. Using statistics to compare mortality rates at different levels of food intake, the researchers found that participants who consumed more butter had a 15% higher risk of death than those who consumed less. Conversely, those who consumed more vegetable oils had a 16% lower risk of death than those who consumed less.
People should consider that a simple change in the diet (replacing butter with soybean or olive oil) can produce significant long-term health benefits,» warns corresponding author Daniel Wang, from the Channing Division of Network Medicine at Brigham and Women’s Hospital. «From a public health perspective, this represents a substantial number of deaths from cancer or other chronic diseases that could be prevented,» he asserts.
The researchers also conducted a substitution analysis, which mimics the impact that replacing butter with vegetable oils in a feeding trial would have on health.
They found that replacing 10 grams of butter per day (less than a tablespoon) with equivalent calories of vegetable oils could reduce cancer deaths and overall mortality by 17%. «Even reducing butter slightly and incorporating more vegetable oils into the daily diet can have significant long-term health benefits,» Wang states.
A limitation of the study is that the participants are mainly healthcare professionals, so they may not represent the overall US population, the researchers said. In the future, they would like to study the biological mechanisms underlying why this dietary change has such a significant impact.
