Consuming higher amounts of unsaturated fats was associated with lower mortality, according to a study from Harvard T.H. Chan School of Public Health. In a large study population followed for more than three decades, researchers found that higher consumption of saturated and trans fats was linked with higher mortality compared with the same number of calories from carbohydrates. Most importantly, replacing saturated fats with unsaturated fats conferred substantial health benefits. This study provides further support for the 2015-2020 Dietary Guidelines for Americans that emphasize the types of fat rather than total amount of fat in the diet.
The study is the most detailed and powerful examination to date on how dietary fats impact health. It suggests that replacing saturated fats like butter, lard, and fat in red meat with unsaturated fats from plant-based foods—such as olive, canola, and soybean oils—can confer substantial health benefits and should continue to be a key message in dietary recommendations.
“There has been widespread confusion in the biomedical community and the general public in the last couple of years about the health effects of specific types of fat in the diet,” said Dong Wang, S.D. ’16, research fellow in the Department of Nutrition at Harvard Chan School and lead author of the study. “This study documents important benefits of unsaturated fats, especially when they replace saturated and trans fats.” Read a Q&A with Wang about the study on the Nutrition Source.