Intended for healthcare professionals

Research

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

BMJ 2006; 332 doi: https://doi.org/10.1136/bmj.38755.366331.2F (Published 30 March 2006) Cite this as: BMJ 2006;332:752

Find the Pony

The BMJ must have known that this paper would lead to headlines such
as
“Debunked!” (Independent) and “The benefits of fish and linseed oils as
elixir
of life are another health myth” (Times) — statements that are
unjustified, but
useful to the pharmaceutical industry — even though the paper does not
claim to show this (the abstract says ” ...omega 3 fats do not have a
clear
effect...”), and the accompanying editorial hardly condemns omega 3
supplementation.

Richard Smith has written on this (1), as has Richard Horton (2).
Mind you, the
BMJ did publish the manual on how to do it (3) — and yes, I do know it was

humorous, but I think most of this paper comes under “FPSU (Find the Pony
Statistical Unit); Execute sub-n-group analysis where n=keep going until
you
find a statistically significant effect in your favour.”

Meta-analysis (which the media always describes as “new research”
— does
nobody in biomedical publication worry about that?) is being debased as a
tool to discredit non-pharmaceutical treatments. In the last 3 years there
has
been a series of such studies, each declared as new research, and each
arguably a variation on Find the Pony. The problem of course is that to
adequately peer-review a meta-analysis it is necessary to peer-review all
the
papers it uses, AND those it excludes, in order to judge the selection
criteria.
The selection process in Hooper et al has already been extensively
criticised
here by others.

Any analysis of the effects of increasing omega 3 intake alone
contributes to
the medicalisation of nutrition; while the drug model of intervention
requires
a single intervention to yield an effect, nutrition is an integrative
approach
involving all aspects of diet and lifestyle. Nobody who understands this
would
expect taking omega 3s to over-ride the effects of smoking, eating high-
calorie junk food and trans-fats, being overweight and taking insufficient

exercise etc.

On the basis of cui bono? it is noteworthy that the only stated
competing
interest in the Hooper paper is the receipt of fees from Solvay Heathcare,
who
market Omacor — the first ever prescription-only fish oil. In September
2005,
Solvay and Pronova Biocare signed a licensing agreement for exclusive
distribution rights on Omacor. Whether intentionally or not, this paper
will
help to persuade patients to shun OTC fish-oil supplements, ignore
nutritional and lifestyle recommendations, and elect for the prescription-
only
version.

1. Smith R, Medical Journals Are an Extension of the Marketing Arm of

Pharmaceutical Companies. PLOS Medicine 2 (5): e138
2. Horton R (2004) The dawn of McScience. New York Rev Books 51(4): 7–9
3. Sackett DL, Oxman AD (2003) HARLOT plc: An amalgamation of the world's
two oldest professions. BMJ 327: 1442–1445

Competing interests:
I help patients with diets and
supplements

Competing interests: No competing interests

17 April 2006
Damien Downing
Ecological physician, journal editor
Journal of Nutritional and Environmental Medicine