A new study suggests that replacing butter with plant-based oils like soybean, canola, and olive oil could significantly improve health and lower the risk of premature death.
Researchers from Mass General Brigham, Harvard T.H. Chan School of Public Health, and the Broad Institute of MIT and Harvard found that people who consumed more plant-based oils had a lower risk of death from all causes, including cancer and heart disease, while those who ate more butter faced a higher risk.
The study, published in JAMA Internal Medicine and presented at a major American Heart Association conference, analyzed data from over 200,000 people who were followed for more than 30 years.
The results showed that swapping butter for plant-based oils could reduce the risk of death by 17%.
Why Are Plant-Based Oils Healthier?
The key difference between butter and plant oils lies in the types of fats they contain. Butter is rich in saturated fatty acids, which have been linked to an increased risk of heart disease and other health problems. In contrast, plant-based oils contain more unsaturated fatty acids, which are considered healthier for the heart.
While many studies have examined the effects of dietary fats, fewer have focused on their primary food sources. This new research provides strong evidence that choosing plant-based oils over butter can lead to long-term health benefits.
How the Study Was Conducted
The researchers analyzed dietary data from 221,054 participants in three large health studies: the Nurses’ Health Study (NHS), Nurses’ Health Study II (NHSII), and Health Professionals Follow-up Study (HPFS). Every four years, participants reported how often they consumed specific foods, including butter and plant oils.
Butter intake was measured from various sources, including:
- Butter and margarine blends
- Butter spreads
- Butter used in cooking and baking
Plant-based oil intake was estimated based on reported use in:
- Frying and sautéing
- Baking
- Salad dressings
The researchers tracked deaths among the participants and their causes. They found that people who ate the most butter had a 15% higher risk of death, while those who consumed the most plant oils had a 16% lower risk of deathcompared to those who ate the least.
Small Dietary Changes Can Have Big Health Benefits
Lead researcher Yu Zhang, MBBS, from Brigham and Women’s Hospital and Harvard, was surprised by the impact of replacing butter with plant oils. “A 17% lower risk of death just by making this simple swap is a huge effect on health,” Zhang said.
To better understand the impact of this change, the researchers conducted a “substitution analysis,” which estimated how swapping butter for plant oils in daily diets would affect health over time. They found that replacing just 10 grams of butter per day (less than a tablespoon) with plant-based oils could significantly lower the risk of death from cancer and other diseases.
“Even small changes, like reducing butter intake slightly and using more plant-based oils, can have meaningful long-term health benefits,” said Dr. Daniel Wang, a senior researcher at Harvard and the Broad Institute.
Public Health Implications
From a public health perspective, these findings suggest that many deaths from chronic diseases like cancer and heart disease could be prevented by making simple dietary adjustments. Swapping butter for plant oils is an easy and practical step that most people can take to improve their health.
However, the researchers acknowledged some limitations in their study. Since most participants were health professionals, their dietary habits may not fully represent the general U.S. population. Future studies will aim to explore the biological reasons behind why plant oils provide such significant health benefits.
Final Thoughts
This study adds strong evidence to the growing body of research that supports plant-based diets for better health. While butter is commonly used in cooking and baking, even small reductions in its intake, replaced by healthier oils like olive, soybean, or canola oil, could lead to significant health improvements.
For those looking to improve their diet, switching to plant-based oils may be one of the simplest and most effective changes to promote a longer and healthier life.
If you care about nutrition, please read studies about the benefits of low-dose lithium supplements, and low calorie diets may help reverse type 2 diabetes.
For more health information, please see recent studies about the best and worst foods for high blood pressure, and time-restricted eating: a simple way to fight aging and cancer
The research findings can be found in JAMA Internal Medicine.
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