Match!

The effect of replacing saturated fat with mostly n-6 polyunsaturated fat on coronary heart disease: a meta-analysis of randomised controlled trials.

Published on Dec 1, 2017in Nutrition Journal3.59
· DOI :10.1186/s12937-017-0254-5
Steven Hamley5
Estimated H-index: 5
(Deakin University)
Cite
Abstract
A cornerstone of conventional dietary advice is the recommendation to replace saturated fatty acids (SFA) with mostly n-6 polyunsaturated fatty acids (PUFA) to reduce the risk of coronary heart disease (CHD). Many clinical trials aimed to test this advice and have had their results pooled in several meta-analyses. However, earlier meta-analyses did not sufficiently account for major confounding variables that were present in some of those trials. Therefore, the aim of the study was to account for the major confounding variables in the diet heart trials, and emphasise the results from those trials that most accurately test the effect of replacing SFA with mostly n-6 PUFA. Clinical trials were identified from earlier meta-analyses. Relevant trials were categorised as ‘adequately controlled’ or ‘inadequately controlled’ depending on whether there were substantial dietary or non-dietary differences between the experimental and control groups that were not related to SFA or mostly n-6 PUFA intake, then were subject to different subgroup analyses. When pooling results from only the adequately controlled trials there was no effect for major CHD events (RR = 1.06, CI = 0.86–1.31), total CHD events (RR = 1.02, CI = 0.84–1.23), CHD mortality (RR = 1.13, CI = 0.91–1.40) and total mortality (RR = 1.07, CI = 0.90–1.26). Whereas, the pooled results from all trials, including the inadequately controlled trials, suggested that replacing SFA with mostly n-6 PUFA would significantly reduce the risk of total CHD events (RR = 0.80, CI = 0.65–0.98, P = 0.03), but not major CHD events (RR = 0.87, CI = 0.70–1.07), CHD mortality (RR = 0.90, CI = 0.70–1.17) and total mortality (RR = 1.00, CI = 0.90–1.10). Available evidence from adequately controlled randomised controlled trials suggest replacing SFA with mostly n-6 PUFA is unlikely to reduce CHD events, CHD mortality or total mortality. The suggestion of benefits reported in earlier meta-analyses is due to the inclusion of inadequately controlled trials. These findings have implications for current dietary recommendations.
Figures & Tables
  • References (81)
  • Citations (21)
Cite
References81
Newest
#1Christopher E. Ramsden (UNC: University of North Carolina at Chapel Hill)H-Index: 16
#2Daisy Zamora (UNC: University of North Carolina at Chapel Hill)H-Index: 11
Last.Joseph R. Hibbeln (NIH: National Institutes of Health)H-Index: 46
view all 10 authors...
#1Lee Hooper (UEA: University of East Anglia)H-Index: 51
#2Nicole Martin (Lond: University of London)H-Index: 7
Last.George Davey-Smith (UoB: University of Bristol)H-Index: 177
view all 4 authors...
#1Henry Boardman (John Radcliffe Hospital)H-Index: 9
#2Louise Hartley (Warw.: University of Warwick)H-Index: 31
Last.Beatrice Knight (University of Exeter)H-Index: 14
view all 8 authors...
#1Zoë Harcombe (University of the West of Scotland)H-Index: 7
#2Julien S. Baker (University of the West of Scotland)H-Index: 21
Last.Fergal M. Grace (University of the West of Scotland)H-Index: 17
view all 7 authors...
#1Maryam Sadat Farvid (Shahid Beheshti University of Medical Sciences and Health Services)H-Index: 1
#2Ming Ding (Harvard University)H-Index: 10
Last.Frank B. Hu (Harvard University)H-Index: 202
view all 8 authors...
Cited By21
Newest
#1A. Astrup (UCPH: University of Copenhagen)H-Index: 92
#2Nina Rica Wium Geiker (UCPH: University of Copenhagen)H-Index: 10
Last.Faidon Magkos (UCPH: University of Copenhagen)H-Index: 43
view all 3 authors...
#1Ilkem Demirkesen (Laos Ministry of Agriculture and Forestry)
#2Behic Mert (METU: Middle East Technical University)H-Index: 9
#1Penny M. Kris-Etherton (PSU: Pennsylvania State University)H-Index: 88
#2Kristina S. Petersen (PSU: Pennsylvania State University)H-Index: 9
Last.Linda Van Horn (NU: Northwestern University)H-Index: 72
view all 3 authors...
View next paperMeta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease