Butter vs. Plant Oils: Impact on Mortality Rates

Recent research published in JAMA Internal Medicine has highlighted significant associations between the consumption of butter and various plant-based oils with mortality rates. The findings indicate that dietary fats play a crucial role in health outcomes, particularly in relation to cardiovascular disease and cancer mortality.

Key Findings

• High butter consumption was associated with a 15% increase in overall mortality.
• Interestingly, using butter for cooking did not seem to significantly impact mortality rates.
• Conversely, a high intake of plant-based oils correlated with a 16% reduction in mortality.
• The effects varied depending on the specific type of oil consumed; for example, corn and safflower oils showed no significant associations.

The Composition of Fats

This study aimed to elucidate the differential impacts of butter, which is high in saturated fats, and unsaturated plant-based oils, predominantly comprised of healthier fats. Past research supports the consumption of unsaturated fats while advising against saturated fats and trans fats

[2]. However, dietary fats are rarely consumed in isolation, making it essential to examine the overall contribution of each food source.

Methodology of the Study

The researchers utilized data from three extensive cohorts: the Nurses’ Health Study, the Nurses’ Health Study II, and the Health Professionals Follow-up Study, encompassing a total of 221,054 adults and a follow-up period of up to 33 years. Participants reported their butter and plant-based oil intake through food frequency questionnaires administered every four years.

Butter Consumption and Mortality Rates

The analysis revealed that those consuming the highest amounts of butter had a 15% higher risk of total mortality when compared to those with the lowest intake. It was noteworthy that the method of butter usage also played a role. The study found no significant mortality association when butter was used for cooking, likely due to smaller quantities consumed.

However, when butter was added to foods such as bread, a direct 4% increase in mortality risk was noted for every additional 5 grams of butter consumed daily.

Plant-Based Oils: A Healthier Alternative

Conversely, participants who favored plant-based oils exhibited a 16% lower rate of mortality. Even when olive oil was excluded from the analysis, results indicated an 8% reduction in mortality still persisted. Analyzing specific oils showed that greater consumption of canola, soybean, and olive oil was linked to lower mortality rates, while corn and safflower oils showed no such associations.

Concerns Regarding Corn and Safflower Oils

The lack of association between corn oil and mortality raises questions due to its potential oxidation during cooking and the possible presence of trans fats. While these results provide compelling insights, the authors advise caution in interpreting these findings, as the relatively low consumption rates of corn and safflower oil may affect the reliability of conclusions drawn.

Cause-Specific Mortality Insights

The study further analyzed cause-specific mortality, focusing on cancer and cardiovascular diseases. Results mirrored the overall mortality trends:

Dietary Recommendations

In light of these findings, substituting butter with plant-based oils emerges as a beneficial dietary intervention. A substitution analysis indicated that replacing 10 grams of butter with plant-based oils could lead to a 17% reduction in total mortality and a 6% reduction in cancer mortality. The results underscore the importance of minimizing saturated fatty acids in favor of unsaturated alternatives, aligning with guidelines from the American Heart Association.

Conclusion

Ultimately, this research reinforces the notion that even small dietary changes, such as transitioning from butter to plant-based oils, can have profound implications for long-term health. As suggested, replacing just three small pats of butter with one tablespoon of plant-based oil daily can significantly reduce the risk of premature mortality.

References

[1] Zhang, Y., et al. (2025). Butter and Plant-Based Oils Intake and Mortality. JAMA Internal Medicine, e250205.

[2] Jakobsen, M. U., et al. (2009). Major types of dietary fat and risk of coronary heart disease: a pooled analysis of 11 cohort studies. The American Journal of Clinical Nutrition, 89(5), 1425–1432.

[3] Trevisan, M., et al. (1990). Consumption of olive oil, butter, and vegetable oils and coronary heart disease risk factors. JAMA, 263(5), 688–692.

[4] Hu F. B. (2003). Plant-based foods and prevention of cardiovascular disease: an overview. The American Journal of Clinical Nutrition, 78(3 Suppl), 544S–551S.