A systematic review of 17 randomized trials involving 66,337 adults found that reducing or modifying saturated fat intake offers little or no clinically meaningful benefit over five years for people at low cardiovascular risk, but may lead to important reductions in mortality and major cardiovascular events among those at high risk, particularly when saturated fat is replaced with polyunsaturated fat. Using standard Cochrane methods and data from MEDLINE, Embase, and the Cochrane Central Register through July 2025, the review showed low- to moderate-certainty evidence for modest relative reductions in all-cause mortality, cardiovascular mortality, nonfatal myocardial infarction, and stroke, with absolute benefits falling below thresholds of importance in low-risk populations but exceeding them in high-risk groups. Notably, replacing saturated fat with polyunsaturated fat was associated with a more pronounced reduction in nonfatal myocardial infarction, while evidence was limited for replacement with monounsaturated fat or protein. Considerable variation across trials in dietary interventions and effectiveness highlights ongoing uncertainty and the need for new, well-designed studies. Source: https://www.acpjournals.org/
