Swapping out the butter in your diet for olive, soybean or canola oil may help you live longer, a new study suggests.
Researchers who analyzed the eating habits of 221,054 people for more than 30 years found that replacing 10 grams of butter — less than 1 tablespoon — each day with plant-based oils reduced the risk of death, including from cancer, by 17%. The people who ate the largest amounts of butter were 15% more likely to die than those who ate the least. Similarly, those who consumed the most plant-based oils were 16% less likely to die than those who consumed the fewest amount.
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The primary difference between butter and plant-based oils is that butter has large amounts of saturated fatty acids, researchers said. The American Heart Association recommends people get less than 6% of their daily calories from saturated fats, which can increase cholesterol and risks of heart disease. In a 2,000-calorie diet, that equates to about 120 calories, or 13 grams.
Plant-based oils have more monounsaturated fatty acids, which help reduce inflammation and lower the risk of chronic diseases. These fats also can be found in avocados, peanut butter and some nuts and seeds, including almonds, pecans and sesame seeds.
"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," said study author Dr. Daniel Wang, of Brigham and Women's Hospital in Boston. "From a public health perspective, this is a substantial number of deaths from cancer or from other chronic diseases that could be prevented."
Replacing butter with plant-based oils, specifically olive oil, has long been shown to improve health outcomes. A 2020 study showed that people who ate more than a half tablespoon of olive oil per day had a 21% lower risk of coronary heart disease and a 15% lower risk of any kind of cardiovascular disease.
A 2022 study found that replacing 2 tablespoons of butter, mayonnaise or dairy fat with olive oil every day lowered overall risk of death by 34% compared to people who ate little to none. Olive oil also has been linked to improved cognitive function and lowering chances for Alzheimer's and dementia-related deaths.
For the latest study, researchers relied on data from people who participated in three other studies between 1990 and 2023. Every four years, participants were asked questions about often they ate certain types of food. Butter consumption included spreadable butter, butter and margarine blends and butter used for baking and frying foods. Plant-based oils included those used in salad dressings and when frying, sautéing and baking foods.
