Intended for healthcare professionals

Rapid response to:


Risks and benefits of omega 3 fats for mortality, cardiovascular disease, and cancer: systematic review

BMJ 2006; 332 doi: (Published 30 March 2006) Cite this as: BMJ 2006;332:752

Rapid Response:

Clear benefit or no clear benefit, that is the question

The Hooper
et al
exclusion criteria underpinning the sweeping conclusion that
".. omega-3 fats have no clear [sic] effect on total mortality,.."
needs to be questioned if only because they allowed the inclusion of the MARGARIN trial [Bemelmans,
] while excluding the larger Lyon
trial on which the former was 'inspired' and that was halted early because of a mortality benefit from a high omega-3, low omega-6 canola oil margarine. Lyon was supported by analysis of blood fatty acids demonstrating the targeted efficacy of its omega-3 canola (rapeseed) based intervention and with other fatty acids changing less than 11% up or down.

Unlike Lyon, the MARGARIN study was confounded by a massive intake of omega-6 linoleic acid and predictably no effect was found; indeed, Figure 2 of the Hooper et al analysis shows the odd ball nature
of that trial. Excluding MARGARIN and including Lyon instead, the virtually significant mortality reduction of 14% might well have become so and I propose that anyone should be enthused by the finding of such nutrient rather than drug-based finding of even this meta analysis.

Plant and fish based omega-3 fatty acids have important and complementary roles supported by many avenues of research and supplement based marine omega-3's have the added advantage of not necessarily depleting fish stocks
and thus being a sustainable source of such fatty acids.

Competing interests:
None declared

Competing interests: No competing interests

31 March 2006
Eddie Vos
Sutton (Qc) Canada J0E 2K0