The researchers found that participants who ate the most butter had a 15% higher risk of dying than those who ate the least. On the other hand, those who ate the most plant-based oils had a 16% lower risk of death than those who ate the least.

“People might want to consider that a simple dietary swap, replacing butter with soybean or olive oil, can lead to significant long-term health benefits. From a public health perspective, this is a substantial number of deaths from cancer or from other chronic diseases that could be prevented,” corresponding author Daniel Wang, MD, ScD, said.

The researchers also ran a substitution analysis to see how replacing butter with plant oils might affect health. They found that swapping just 10 grams of butter a day (less than a tablespoon) for the same calories from plant oils could reduce cancer deaths and overall mortality by 17%.

“Even cutting back butter a little and incorporating more plant-based oils into your daily diet can have meaningful long-term health benefits,” Wang said.