A new study led by researchers from Mass General Brigham, Harvard T.H. Chan School of Public Health, and the Broad Institute of MIT and Harvard suggests that substituting plant-based oils for butter in daily diets may significantly improve health and reduce the risk of premature death.
The study, which analyzed over 30 years of data from 200,000 participants, found that higher consumption of plant-based oils—particularly soybean, canola, and olive oil—was associated with lower mortality rates from cancer and cardiovascular diseases. In contrast, higher butter intake was linked to an increased risk of total mortality and cancer-related deaths.
Published in JAMA Internal Medicine and presented at the American Heart Association’s EPI/Lifestyle Scientific Sessions, the study highlights a striking finding: replacing butter with plant-based oils in daily meals could lower the risk of death by as much as 17%.
“The magnitude of the effect we observed is quite significant,” said Yu Zhang, MBBS, the lead author of the study and a research assistant at the Channing Division of Network Medicine at Brigham and Women’s Hospital. “This is a major shift in terms of potential health benefits.”
The key difference between butter and plant-based oils lies in their fatty acid profiles. Butter is high in saturated fats, while plant-based oils contain healthier unsaturated fats. Although previous research has examined dietary fatty acids, this study is one of the few to investigate the direct effects of butter and plant oils as primary food sources.
Unlike many earlier studies that focused on short-term dietary habits in small populations, this new study utilized data from large, long-term health studies: the Nurses’ Health Study (NHS), Nurses’ Health Study II (NHSII), and Health Professionals Follow-up Study (HPFS). Every four years, participants provided detailed information on their food consumption, including butter and plant oils. The researchers then correlated this dietary data with mortality rates and causes of death.
The results revealed a clear association between higher butter intake and increased death risk. Participants who consumed the most butter had a 15% higher risk of dying compared to those with the lowest intake. On the other hand, those who used more plant-based oils saw a 16% lower risk of death.
“People should consider that a simple dietary swap—replacing butter with oils like soybean or olive oil—could lead to significant long-term health benefits,” said Dr. Daniel Wang, MD, ScD, a corresponding author of the study. Wang, an assistant professor at Harvard Chan School and an associate member of the Broad Institute, emphasized the potential for public health improvements by reducing deaths from cancer and chronic diseases.
The researchers also conducted a substitution analysis to simulate the effects of replacing butter with plant oils in a controlled trial. They found that swapping just 10 grams of butter (about one teaspoon) with the same calorie amount of plant oils could reduce cancer-related deaths and overall mortality by 17%.
“Even small reductions in butter consumption and more frequent use of plant-based oils can lead to meaningful health improvements,” Wang noted.
One limitation of the study is that its participants were primarily health professionals, which may not fully represent the broader U.S. population. The researchers also expressed interest in exploring the biological mechanisms behind these dietary changes and their impact on health in future studies.
Related topic:
Exercise May Reduce Risk of Dementia and Stroke
Fasting Boosts HGH Secretion, Potentially Reducing Health Risks
Fish Consumption May Slow Disability Progression in MS
