PMID- 32428300 OWN - NLM STAT- MEDLINE DCOM- 20200911 LR - 20220915 IS - 1469-493X (Electronic) IS - 1361-6137 (Linking) VI - 5 IP - 5 DP - 2020 May 19 TI - Reduction in saturated fat intake for cardiovascular disease. PG - CD011737 LID - 10.1002/14651858.CD011737.pub2 [doi] LID - CD011737 AB - BACKGROUND: Reducing saturated fat reduces serum cholesterol, but effects on other intermediate outcomes may be less clear. Additionally, it is unclear whether the energy from saturated fats eliminated from the diet are more helpfully replaced by polyunsaturated fats, monounsaturated fats, carbohydrate or protein. OBJECTIVES: To assess the effect of reducing saturated fat intake and replacing it with carbohydrate (CHO), polyunsaturated (PUFA), monounsaturated fat (MUFA) and/or protein on mortality and cardiovascular morbidity, using all available randomised clinical trials. SEARCH METHODS: We updated our searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (Ovid) and Embase (Ovid) on 15 October 2019, and searched Clinicaltrials.gov and WHO International Clinical Trials Registry Platform (ICTRP) on 17 October 2019. SELECTION CRITERIA: Included trials fulfilled the following criteria: 1) randomised; 2) intention to reduce saturated fat intake OR intention to alter dietary fats and achieving a reduction in saturated fat; 3) compared with higher saturated fat intake or usual diet; 4) not multifactorial; 5) in adult humans with or without cardiovascular disease (but not acutely ill, pregnant or breastfeeding); 6) intervention duration at least 24 months; 7) mortality or cardiovascular morbidity data available. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed inclusion, extracted study data and assessed risk of bias. We performed random-effects meta-analyses, meta-regression, subgrouping, sensitivity analyses, funnel plots and GRADE assessment. MAIN RESULTS: We included 15 randomised controlled trials (RCTs) (16 comparisons, ~59,000 participants), that used a variety of interventions from providing all food to advice on reducing saturated fat. The included long-term trials suggested that reducing dietary saturated fat reduced the risk of combined cardiovascular events by 21% (risk ratio (RR) 0.79; 95% confidence interval (CI) 0.66 to 0.93, 11 trials, 53,300 participants of whom 8% had a cardiovascular event, I(2) = 65%, GRADE moderate-quality evidence). Meta-regression suggested that greater reductions in saturated fat (reflected in greater reductions in serum cholesterol) resulted in greater reductions in risk of CVD events, explaining most heterogeneity between trials. The number needed to treat for an additional beneficial outcome (NNTB) was 56 in primary prevention trials, so 56 people need to reduce their saturated fat intake for ~four years for one person to avoid experiencing a CVD event. In secondary prevention trials, the NNTB was 32. Subgrouping did not suggest significant differences between replacement of saturated fat calories with polyunsaturated fat or carbohydrate, and data on replacement with monounsaturated fat and protein was very limited. We found little or no effect of reducing saturated fat on all-cause mortality (RR 0.96; 95% CI 0.90 to 1.03; 11 trials, 55,858 participants) or cardiovascular mortality (RR 0.95; 95% CI 0.80 to 1.12, 10 trials, 53,421 participants), both with GRADE moderate-quality evidence. There was little or no effect of reducing saturated fats on non-fatal myocardial infarction (RR 0.97, 95% CI 0.87 to 1.07) or CHD mortality (RR 0.97, 95% CI 0.82 to 1.16, both low-quality evidence), but effects on total (fatal or non-fatal) myocardial infarction, stroke and CHD events (fatal or non-fatal) were all unclear as the evidence was of very low quality. There was little or no effect on cancer mortality, cancer diagnoses, diabetes diagnosis, HDL cholesterol, serum triglycerides or blood pressure, and small reductions in weight, serum total cholesterol, LDL cholesterol and BMI. There was no evidence of harmful effects of reducing saturated fat intakes. AUTHORS' CONCLUSIONS: The findings of this updated review suggest that reducing saturated fat intake for at least two years causes a potentially important reduction in combined cardiovascular events. Replacing the energy from saturated fat with polyunsaturated fat or carbohydrate appear to be useful strategies, while effects of replacement with monounsaturated fat are unclear. The reduction in combined cardiovascular events resulting from reducing saturated fat did not alter by study duration, sex or baseline level of cardiovascular risk, but greater reduction in saturated fat caused greater reductions in cardiovascular events. CI - Copyright (c) 2020 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. FAU - Hooper, Lee AU - Hooper L AD - Norwich Medical School, University of East Anglia, Norwich, UK. FAU - Martin, Nicole AU - Martin N AD - Institute of Health Informatics Research, University College London, London, UK. FAU - Jimoh, Oluseyi F AU - Jimoh OF AD - Norwich Medical School, University of East Anglia, Norwich, UK. FAU - Kirk, Christian AU - Kirk C AD - Norwich Medical School, University of East Anglia, Norwich, UK. FAU - Foster, Eve AU - Foster E AD - Norwich Medical School, University of East Anglia, Norwich, UK. FAU - Abdelhamid, Asmaa S AU - Abdelhamid AS AD - Norwich Medical School, University of East Anglia, Norwich, UK. LA - eng SI - ClinicalTrials.gov/NCT00000611 SI - ClinicalTrials.gov/NCT02062424 SI - ClinicalTrials.gov/NCT00692536 SI - ClinicalTrials.gov/NCT01954472 SI - ClinicalTrials.gov/NCT01005498 SI - ClinicalTrials.gov/NCT01634841 SI - ClinicalTrials.gov/NCT03354377 PT - Journal Article PT - Meta-Analysis PT - Research Support, Non-U.S. Gov't PT - Systematic Review DEP - 20200519 PL - England TA - Cochrane Database Syst Rev JT - The Cochrane database of systematic reviews JID - 100909747 RN - 0 (Dietary Carbohydrates) RN - 0 (Dietary Fats) RN - 0 (Dietary Fats, Unsaturated) RN - 0 (Dietary Proteins) RN - 0 (Fatty Acids) RN - 97C5T2UQ7J (Cholesterol) SB - IM UOF - Cochrane Database Syst Rev. 2015 Jun 10;(6):CD011737. PMID: 26068959 UIN - Cochrane Database Syst Rev. 2020 Aug 21;8:CD011737. PMID: 32827219 MH - Adult MH - Cardiovascular Diseases/mortality/*prevention & control MH - Cause of Death MH - Cholesterol/blood MH - Dietary Carbohydrates/administration & dosage MH - Dietary Fats/*administration & dosage MH - Dietary Fats, Unsaturated/administration & dosage MH - Dietary Proteins/administration & dosage MH - Energy Intake MH - Fatty Acids/*administration & dosage MH - Female MH - Humans MH - Male MH - Myocardial Infarction/mortality/prevention & control MH - Randomized Controlled Trials as Topic MH - Stroke/prevention & control PMC - PMC7388853 COIS- Lee Hooper: LH is a member of the World Health Organization Nutrition Guidance Expert Advisory Group (NUGAG). WHO paid for her travel, accommodation and expenses to attend NUGAG meetings in Geneva, China and South Korea where the evidence of effects of dietary fats on health was discussed and guidance developed. LH's institution was given grant funding from WHO to carry out the 2019 update of this systematic review, to update a systematic review on the relationship between total fat intake and body weight and a series of systematic reviews on the health effects of polyunsaturated fatty acids. Nicole Martin: None known Asmaa Abdelhamid: None known Oluseyi Florence Jimoh: This review was funded by a grant from the World Health Organization. Eve Foster: None known Christian Kirk: None known EDAT- 2020/05/20 06:00 MHDA- 2020/09/12 06:00 PMCR- 2021/05/19 CRDT- 2020/05/20 06:00 PHST- 2020/05/20 06:00 [entrez] PHST- 2020/05/20 06:00 [pubmed] PHST- 2020/09/12 06:00 [medline] PHST- 2021/05/19 00:00 [pmc-release] AID - CD011737.pub2 [pii] AID - 10.1002/14651858.CD011737.pub2 [doi] PST - epublish SO - Cochrane Database Syst Rev. 2020 May 19;5(5):CD011737. doi: 10.1002/14651858.CD011737.pub2.