Huge Diet Study: More Butter, More Problems

 

Ask your competent? doctor to make this useful to you by explaining EXACTLY how replacing dairy fat with plant oils helps you, because I'm seeing research suggesting dairy fat is good for you. Your doctor should know more than me since I'm not medically trained. No explanation, then you don't have a functioning stroke doctor.

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• butter (4 posts to December 2016)

Dairy fat from milk, butter, and cheese could actually PREVENT a heart attack September 2021

The latest here:

Huge Diet Study: More Butter, More Problems

       Survival benefit was tied to plant-based oils, including affordable alternatives to olive oil

by Nicole Lou, Senior Staff Writer, MedPage Today March 6, 2025

Key Takeaways

• A higher intake of butter was tied to a higher mortality risk in a large study.
• A higher intake of plant-based oil was linked with a lower mortality risk.
• Plant oils associated with survival benefit were olive, soybean, and canola oils.

A large-scale longevity study suggested that more butter is bad, more plant oils are good -- and substituting plant-based oils for butter translated into better survival over several decades.

After 33 years of follow-up, deaths were disproportionately more likely among people in the highest quartile versus the lowest quartile of butter consumption (HR 1.15, 95% CI 1.08-1.22). The opposite was true for the relationship between mortality and plant-based oil consumption as the latter appeared more protective (HR 0.84, 95% CI 0.79-0.90), even when olive oil was excluded from this category (HR 0.92, 95% CI 0.86-0.98).

Substituting 10 g of butter intake per day with an equivalent amount of total plant-based oils was associated with a survival benefit (HR 0.83, 95% CI 0.79-0.86). This applied to prevention of cancer deaths in particular (HR 0.83, 95% CI 0.76-0.90), whereas cardiovascular disease (CVD) mortality was not affected by the switch (HR 0.94, 95% CI 0.86-1.03), reported Dong Wang, MD, ScD, of Brigham and Women's Hospital and Harvard Medical School in Boston, and colleagues in JAMA Internal Medicine.

"The present findings are closely aligned with the dietary recommendations of the American Heart Association 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," Wang's group wrote. "The present results indicate that replacing three small pats of butter (approximately 15 g) with 1 tablespoon of plant-based oil (approximately 15 g) in the daily diet could contribute to lowering the risk of premature mortality."

There has been a longstanding debate about the health effects of butter. Studies have traditionally linked it to adverse health outcomes, but the evidence has been inconsistent and separate from the plant oil literature. In the present study, the investigators made it a point to explicitly compare butter with alternative oils.

Yong-Moon Mark Park, MD, PhD, and Yikyung Park, ScD, both of the University of Arkansas for Medical Sciences in Little Rock, emphasized that not all plant-based oils are equally healthy based on the latest results.

In the study, the risk of mortality was significantly reduced with every 5-g increase in daily intake of canola oil (HR 0.85, 95% CI 0.78-0.92), soybean oil (HR 0.94, 95% CI 0.91-0.96), and olive oil (HR 0.92, 95% CI 0.91-0.94).

"While olive, soybean, and canola oils are associated with reduced mortality risk, this was not observed for corn and safflower oils," Park and Park wrote in an invited commentary. "However, this association may not be robust due to the relatively low consumption of these oils compared with other plant oils in the study population. Additionally, there are other plant-based oils, such as palm oil and coconut oil, that were not examined in the study but have been linked to adverse health outcomes in other studies," the duo cautioned.

Park and Park nevertheless cited various mechanisms that could explain the study's general findings favoring plant-based oils. "Butter's high saturated fat and cholesterol content, alongside its lower levels of beneficial nutrients, make it less suitable for long-term health. In contrast, plant-based oils, enriched with unsaturated fatty acids (including omega-3 fatty acids) and bioactive compounds, provide antioxidative and anti-inflammatory properties that protect against chronic diseases and premature mortality."

"Therefore, substituting these oils for butter may promote longevity and reduce cancer-related deaths. Dietary guidelines should emphasize the use of plant-based oils while minimizing saturated fats, like butter, for optimal health outcomes," the editorialists concluded.

For their prospective population-based cohort study, Wang's group included over 220,000 adults who were free of cancer, CVD, diabetes, or neurodegenerative disease at baseline from three large datasets: the Nurses' Health Study (all women, mean age of 56.1), the Nurses' Health Study II (all women, mean age of 36.1), and the Health Professionals Follow-up Study (all men, mean age of 56.3).

Eating habits logged in these studies were linked to U.S. mortality data taken from nationwide records and assigned causes based on death certificates and medical records. There were 50,932 deaths identified for the study, including 12,241 from cancer and 11,240 from CVD.

Study participants had answered semiquantitative food frequency questionnaires every 4 years, reporting the frequency and quantity of specific foods, types of fats and oils, and the brands or types of oils used for cooking and added at the table over the preceding year.

People in the highest quartile by butter intake self-reported eating just under three small pats of butter per day. Those in the highest quartile by plant oil consumption ate about 1.5 tablespoons of it daily.

The study's main findings were generally supported when survival analyses were conducted considering butter and oil consumption in incremental increases instead of quartiles.

Total mortality correlated with every 5-g daily consumption of butter added to food or bread (HR 1.04 per 5-g/d increase, 95% CI 1.02-1.05). Every 10 g of more butter per day was associated with higher cancer mortality (HR 1.12, 95% CI 1.04-1.20), while every 10-g daily increase in plant-based oils intake was associated with significantly less cancer mortality (HR 0.89, 95% CI 0.85-0.94) and less CVD mortality (HR 0.94, 95% CI 0.89-0.99).

The 10-g incremental butter showed no association with CVD mortality. There was no total mortality signal from incremental increases in butter from baking or frying, either (HR 1.00 per 5-g/d increase, 95% CI 0.94-1.07).

Wang and colleagues acknowledged the smaller quantities of butter used for baking and frying may have limited their ability to detect the health effects of this practice.

They urged further investigation of the molecular mechanisms underlying the metabolic effects of butter and plant-based oils.

"One notable limitation is a lack of consideration for the role of individual socioeconomic status (SES). Although the cohort's homogeneous SES may reduce SES-related confounding, variations within this study population could still affect dietary choices and health outcomes. Even among individuals with higher SES, food costs may influence dietary choices and contribute to health disparities," noted Park and Park.

"In this context, it is important to consider the affordability of various healthy fats," the editorialists stressed. "This suggests that more affordable options, such as canola and soybean oils, may serve as accessible alternatives to olive oil, which tends to be more expensive."

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  Nicole Lou is a reporter for MedPage Today, where she covers cardiology news and other developments in medicine. Follow

Disclosures

The study was funded by various NIH grants.

Wang had no disclosures. Co-authors disclosed relationships with the Novo Nordisk Foundation, the International Nut and Dried Fruit Council, and the NIH.

Park reported support from a National Heart, Lung, and Blood Institute grant.

Primary Source

JAMA Internal Medicine

Source Reference: Zhang Y, et al "Butter and plant-based oils intake and mortality" JAMA Intern Med 2025; DOI: 10.1001/jamainternmed.2025.0205.

Secondary Source

JAMA Internal Medicine

Source Reference: Park YM, Park Y "To butter or replace with plant-based oils, that is the question" JAMA Intern Med 2025; DOI: 10.1001/jamainternmed.2025.0203.