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Cited by 523Fatty Acid Research and HealthNutritional Studies and DietLipoproteins and Cardiovascular Health

Use of dietary linoleic acid for secondary prevention of coronary heart disease and death: evaluation of recovered data from the Sydney Diet Heart Study and updated meta-analysis

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Ramsden, C. E., Zamora, D., Leelarthaepin, B., Majchrzak-Hong, S. F., Faurot, K. R., Suchindran, C. M., Ringel, A., Davis, J. M. +1 more·2013·BMJ
DOI 10.1136/bmj.e8707PMC PMC4688426
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Abstract

OBJECTIVE: To evaluate the effectiveness of replacing dietary saturated fat with omega 6 linoleic acid, for the secondary prevention of coronary heart disease and death. DESIGN: Evaluation of recovered data from the Sydney Diet Heart Study, a single blinded, parallel group, randomized controlled trial conducted in 1966-73; and an updated meta-analysis including these previously missing data. SETTING: Ambulatory, coronary care clinic in Sydney, Australia. PARTICIPANTS: 458 men aged 30-59 years with a recent coronary event. INTERVENTIONS: Replacement of dietary saturated fats (from animal fats, common margarines, and shortenings) with omega 6 linoleic acid (from safflower oil and safflower oil polyunsaturated margarine). Controls received no specific dietary instruction or study foods. All non-dietary aspects were designed to be equivalent in both groups. OUTCOME MEASURES: All cause mortality (primary outcome), cardiovascular mortality, and mortality from coronary heart disease (secondary outcomes). We used an intention to treat, survival analysis approach to compare mortality outcomes by group. RESULTS: The intervention group (n=221) had higher rates of death than controls (n=237) (all cause 17.6% v 11.8%, hazard ratio 1.62 (95% confidence interval 1.00 to 2.64), P=0.05; cardiovascular disease 17.2% v 11.0%, 1.70 (1.03 to 2.80), P=0.04; coronary heart disease 16.3% v 10.1%, 1.74 (1.04 to 2.92), P=0.04). Inclusion of these recovered data in an updated meta-analysis of linoleic acid intervention trials showed non-significant trends toward increased risks of death from coronary heart disease (hazard ratio 1.33 (0.99 to 1.79); P=0.06) and cardiovascular disease (1.27 (0.98 to 1.65); P=0.07). CONCLUSIONS: Advice to substitute polyunsaturated fats for saturated fats is a key component of worldwide dietary guidelines for coronary heart disease risk reduction. However, clinical benefits of the most abundant polyunsaturated fatty acid, omega 6 linoleic acid, have not been established. In this cohort, substituting dietary linoleic acid in place of saturated fats increased the rates of death from all causes, coronary heart disease, and cardiovascular disease. An updated meta-analysis of linoleic acid intervention trials showed no evidence of cardiovascular benefit. These findings could have important implications for worldwide dietary advice to substitute omega 6 linoleic acid, or polyunsaturated fats in general, for saturated fats. TRIAL REGISTRATION: Clinical trials NCT01621087.

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Authors
Ramsden, C. E., Zamora, D., Leelarthaepin, B., Majchrzak-Hong, S. F., Faurot, K. R., Suchindran, C. M., Ringel, A., Davis, J. M., & Hibbeln, J. R.
Affiliations
  • University of North Carolina at Chapel Hill (US)
  • UNSW Sydney (AU)
  • National Institutes of Health (US)
  • University of Illinois Chicago (US)
Corresponding author
Ramsden, C. E.
ORCID
Venue
BMJ
Publisher
BMJ
Published
2013-02-04
Volume
346
Issue
feb04 3
Pages
e8707-e8707
ISSN
1756-1833 (ISSN-L)
DOI
10.1136/bmj.e8707
PMC
PMC4688426
OpenAlex
W2108791220
Cited by
523
References
2
Citations by year
2026: 16 · 2025: 20 · 2024: 24 · 2023: 28 · 2022: 20 · 2021: 35 · 2020: 37 · 2019: 28 · 2018: 58 · 2017: 37 · 2016: 60 · 2015: 60 · 2014: 65 · 2013: 33
FWCI
67.43
Type
journal article
Language
en
Open access
Licence
cc-by-nc
Locations
  • BMJ (publishedVersion, cc-by-nc)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by-nc)
  • PubMed Central (publishedVersion, cc-by-nc)
  • PubMed (publishedVersion)
  • Carolina Digital Repository (University of North Carolina at Chapel Hill) (submittedVersion)
  • Figshare (submittedVersion, cc-by-nc)
  • UNC Libraries
Funders
  • University of New South Wales
  • National Institutes of Health
  • National Center for Complementary and Integrative Health (T32AT003378)
Topics
  • Health Sciences › Nursing › Nutrition and Dietetics › Fatty Acid Research and Health
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Nutritional Studies and Diet
  • Health Sciences › Medicine › Surgery › Lipoproteins and Cardiovascular Health
Keywords
linoleic acid, omega-6 fatty acids, saturated fat replacement, coronary artery disease, secondary prevention, mortality, safflower oil, dietary guidelines, cardiovascular mortality, cardiovascular risk reduction
MeSH terms
Adult, Coronary Disease, Dietary Fats, Epidemiologic Methods, Humans, Male, Middle Aged, New South Wales, Plant Oils, Diet, Fat-Restricted, Linoleic Acid, Secondary Prevention

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