Substituting Plant-Based Oil for Butter Could Avert Premature Death

Greater butter intake was linked to a magnified risk of total and cancer-related mortality, while substituting with plant-based oil, including olive, soybean, and canola oils, could offer notable benefits for preventing premature death.1

This population-based cohort study identified more than 221,000 adults from 3 large cohorts in the US, including women and men who were free from cancer, cardiovascular disease (CVD), diabetes, or neurodegenerative diseases at baseline, with up to 33 years of follow-up.

“The present findings are closely aligned with the dietary recommendations of the American Heart Association (AHA) and the Dietary Guidelines for Americans, which advocate for reducing saturated fat intake and replacing it with polyunsaturated and monounsaturated fats to lower the risk of chronic disease,” wrote the investigative team, led by Dong D. Wang, MD, ScD, Brigham and Women’s Hospital and Harvard Medical School.

Dietary information was collected from an assessment of the 3 cohorts, including the Nurses’ Health Study (NHS), the Nurses’ Health Study II (NHSII), and the Health Professionals Follow-up Study (HPFS). Overall, 158,463 women and 29,508 men were identified for the final analysis. Based on previously reported long-term epidemiological data, Wang and colleagues hypothesized a link between butter intake and higher mortality and plant-based oils with lower mortality.2

A validated semiquantitative food frequency questionnaire (FFQ) was administered at baseline and every 4 years to determine the number of specific foods, types of fats and oils, and brands used for cooking. Total mortality was identified in the National Death Index, supplemented by information from next of kin, and the cause of death was based on medical records.1

Across nearly 33 years of follow-up, 50,932 deaths were reported, including 12,241 due to cancer and 11,240 due to CVD. Separated into quartiles based on butter or plant-based oil intake (Levels 1 to 4), and adjusted for confounders, the highest intake of butter showed a 15% higher risk of total mortality than the lowest intake (hazard ratio [HR], 1.15; 95% CI, 1.08–1.22; P <.001).

A comparison of the highest to lowest intake of total plant-based oils revealed a 16% reduction in total mortality (HR, 0.84; 95% CI, 0.79–0.90; P <.001). Wang and colleagues identified a statistically significant association between lower death rates and higher intake of canola (HR, 0.85; 95% CI, 0.78–0.92), soybean (HR, 0.94; 95% CI, 0.91–0.96), and olive oils (HR, 0.92; 95% CI, 0.91–0.94) per 5-g/d increments (all P <.001).

Further analysis of cause-specific mortality revealed each 10-g/d rise in plant-based oil intake was associated with an 11% lower risk of cancer mortality (HR, 0.89; 95% CI, 0.85–0.94; P <.001) and a 6% reduced risk of CVD mortality (HR, 0.94; 95% CI, 0.89–0.99; P =.03). Meanwhile, higher butter intake was linked to greater cancer mortality (HR, 1.12; 95% CI, 1.04–1.20; P <.001), but not CVD mortality.

Substitution analysis showed replacement of a 10-g/d intake of total butter with an equivalent of total plant-based oils was linked to an estimated 17% reduction in both cancer mortality (HR, 0.83; 95% CI, 0.76–0.90; P <.001) and total mortality (HR, 0.83; 95% CI, 0.79–0.86; P <.001).

In an accompanying editorial, Yong-Moon Mark Park, MD, PhD, University of Arkansas for Medical Sciences, highlighted the significance of a subgroup analysis suggesting that replacing butter with plant-based oils may provide meaningful health benefits, even for those with suboptimal diets.3

“For individuals with poorer overall diet quality who may find it challenging to adhere to comprehensive dietary recommendations, making a single, achievable change–such as substituting plant-based oils for butter–could still improve health outcomes and reduce mortality risk,” they wrote. “However, it should be noted that this specific substitution was not explicitly examined in the study.”

References

1. Zhang Y, Chadaideh KS, Li Y, et al. Butter and Plant-Based Oils Intake and Mortality. JAMA Intern Med. Published online March 06, 2025. doi:10.1001/jamainternmed.2025.0205

2. Guasch-Ferré M, Liu G, Li Y, et al. Olive Oil Consumption and Cardiovascular Risk in U.S. Adults. J Am Coll Cardiol. 2020;75(15):1729-1739. doi:10.1016/j.jacc.2020.02.036

3. Park YM, Park Y. To Butter or Replace With Plant-Based Oils, That Is the Question. JAMA Intern Med. Published online March 06, 2025. doi:10.1001/jamainternmed.2025.0203