ImpactofReplacementofIndividualDietarySFAs onCirculatingLipidsandOtherBiomarkersof CardiometabolicHealth:ASystematicReviewand Meta-AnalysisofRandomizedControlledTrialsin Humans

Abstract

LittleisknownoftheimpactofindividualSFAsandtheirisoenergeticsubstitutionwithotherSFAsorunsaturatedfattyacids(UFAs)ontheprevention of cardiometabolic disease (CMD). This systematic literature review assessed the impact of such dietary substitutions on a range of fasting CMD risk markers, including lipid profile, markers of glycemic control and inflammation, and metabolic hormone concentrations. Eligible randomized controlledtrials(RCTs)investigatedtheeffectofisoenergeticreplacementsofindividualdietarySFAsfor≥14don≥1CMDriskmarkersinhumans. SearchesofthePubMed,Embase,Scopus,andCochraneCENTRALdatabaseson14February,2021identified44RCTsconductedinparticipantswith amean±SDageof39.9±15.2y.Studies’riskofbiaswasassessedusingtheCochraneRiskofBiastool2.0forRCTs.Random-effectmeta-analyses assessed the effect of ≥3 similar dietary substitutions on the same CMD risk marker. Other dietary interventions were described in qualitative syntheses. WeobservedreductionsinLDL-cholesterolconcentrationsafter thereplacement ofpalmiticacid(16:0) withUFAs (−0.36mmol/L;95% CI:−0.50,−0.21 mmol/L; I2=96.0%, n=18 RCTs) or oleic acid (18:1n–9) (−0.16 mmol/L; 95% CI:−0.28,−0.03 mmol/L; I2=89.6%, n=9 RCTs), withasimilarimpactontotalcholesterolandapoBconcentrations.NoeffectsonotherCMDriskmarkers,includingHDL-cholesterol,triacylglycerol, glucose, insulin, or C-reactive protein concentrations, were evident. Similarly, we found no evidence of a benefit from replacing dietary stearic acid(18:0)withUFAsonCMDriskmarkers(n=4RCTs).Inconclusion,theimpactofreplacingdietarypalmiticacidwithUFAsonlipidbiomarkersis alignedwithcurrentpublichealthrecommendations.However,owingtothehighheterogeneityandlimitedstudies,relationsbetweenallindividual SFAsandbiomarkersofcardiometabolichealthneedfurtherconfirmationfromRCTs.Thissystematicreviewwasregisteredatwww.crd.york.ac.uk/ prospero/asCRD42020084241. AdvNutr2022;13:1200–1225.