Abstract
Background: We hypothesized that due to the absence of a dietary source of omega-3 fatty acids,
the essential fatty acid (EFA) deficiency model leads to an overestimate of linoleic
acid (LA) requirements. Methods: over 7 wk, young rats consumed an EFA diet containing either 0 en% linoleate (0LA) and 0 en% α-linolenate (0LNA) or a diet containing 0.5 en% LNA plus one of seven levels of added LA (0.12–4.0 en%; n=6/group).
Results: Rats consuming the 0LA–0LNA diet had the lowest final body weight, 34–68% lower
LA and arachidonate in plasma and liver, 87% lower LA in epididymal fat, and an 8–20
fold higher eicosatrienoate in plasma, liver and muscle lipids. 0.5LNA completely
prevented the lower growth and partly prevented the rise in eicosatrienoate seen in
the 0LA–0LNA group.
Conclusion: Providing dietary LNA at 0.5 en% reduces the rat's physiological requirement for
LA by an estimated factor of at least four (0.5 en% instead of 2 en%). Since LA requirements in humans are also based on the same flawed model of EFA
deficiency, it is plausible that they too have been overestimated and should therefore
be reinvestigated.
Abbreviations:
AA (arachidonate), DHA (docosahexaenoate), DPA (docosapentaenoate), EFA (essential fatty acids), EPA (eicosapentaenoate), ETA (eicosatrienoate), LA (linoleate), LC-PUFA (long chain PUFA), LNA (α-linolenate), PUFA (polyunsaturated fatty acid.)Keywords
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Article info
Publication history
Published online: August 31, 2011
Accepted:
August 9,
2011
Received in revised form:
July 22,
2011
Received:
April 29,
2011
Footnotes
☆Supported by l'Institut National de la recherche Agronomique (INRA) and the Natural Sciences and Engineering Research Council of Canada (SCC).
☆☆Contributions: PG and SCC jointly designed this project and wrote the paper. PG, MSL, JMA and MJ conducted the research and analyzed the data. PG and SCC had primary responsibility for final content. All authors read and approved the final manuscript.
Identification
Copyright
© 2011 Elsevier Ltd. Published by Elsevier Inc. All rights reserved.
