Article Impact Level: HIGH Data Quality: STRONG Summary of Annals of Internal Medicine https://doi.org/10.7326/ANNALS-25-02229 Dr. Jeremy P. Steen et al.
Points
- This systematic review analyzed seventeen randomized trials to determine if reducing saturated fat benefits mortality and cardiovascular events based on a patient’s baseline risk.
- For individuals at low to intermediate cardiovascular risk, the study found little or no significant benefit from either cutting or replacing their saturated fat intake.
- In contrast, high-risk individuals experienced important reductions in all-cause mortality, cardiovascular mortality, and nonfatal myocardial infarction when reducing their saturated fat consumption.
- The most significant risk reduction was observed when saturated fats were specifically replaced with polyunsaturated fats, which lowered the risk of nonfatal heart attacks.
- These findings suggest that clinical recommendations for saturated fat intake should be tailored to a patient’s individual cardiovascular risk profile rather than applied universally.
Summary
This systematic review and meta-analysis of 17 randomized trials involving 66,337 participants assessed the effect of reducing or modifying saturated fat intake on cholesterol, mortality, and major cardiovascular events. The study stratified evidence by baseline cardiovascular risk to determine the absolute benefits of intervention over a minimum of two years. Overall, reducing saturated fat intake led to significant reductions in total cholesterol and low-density lipoprotein cholesterol (LDL-C), confirming its lipid-lowering effects.
Based on low- to moderate-certainty evidence, interventions aimed at reducing saturated fat intake were associated with potential reductions in all-cause mortality (risk ratio [RR], 0.96 [95% CI, 0.88 to 1.06]), cardiovascular mortality (RR, 0.93 [CI, 0.77 to 1.11]), and nonfatal myocardial infarction (MI) (RR, 0.86 [CI, 0.70 to 1.06]). However, when stratified by risk, the absolute benefits for individuals at low baseline cardiovascular risk were below predefined thresholds of clinical importance. Conversely, for high-risk individuals, the potential absolute reductions in mortality and cardiovascular events were above these thresholds, suggesting clinically meaningful benefits.
The analysis further indicated that the method of replacement is a key determinant of efficacy. Specifically, replacing saturated fat with polyunsaturated fat (PUFA) was associated with a more pronounced risk reduction for nonfatal MI (RR, 0.75 [CI, 0.58 to 0.99]; P for interaction = 0.05). This finding suggests that while saturated fat reduction is most relevant for high-risk populations, the benefits can be enhanced by substituting with PUFA. The authors conclude that dietary advice on saturated fat should be tailored to individual patient risk profiles.
Link to the article: https://www.acpjournals.org/doi/10.7326/ANNALS-25-02229
References
Steen, J. P., Klatt, K. C., Chang, Y., Guyatt, G. H., Zhu, H., Swierz, M. J., Storman, D., Sun, M., Zhao, Y., Ge, L., Thabane, L., Ghosh, N. R., Karam, G., Alonso-Coello, P., Bala, M. M., & Johnston, B. C. (2025). Effect of interventions aimed at reducing or modifying saturated fat intake on cholesterol, mortality, and major cardiovascular events: A risk stratified systematic review of randomized trials. Annals of Internal Medicine, ANNALS-25-02229. https://doi.org/10.7326/ANNALS-25-02229
