Silver Linings in Omega-3 Research

The cardiovascular care category is still among the largest in the supplement industry, but with a lot of recent research, a lot seems to be in flux. With the recent meta-analysis in JAMA leading to the headline “Omega-3’s fizzle for the heart,” one wonders how this finding could actually be true. Has our worldview of omega-3s as the end-all for healthy living crumbled in front of our eyes?

Good news: anyone willing to shell out $30 for the full text of the JAMA study can see some obvious hairs and warts. To begin with, many of the studies included in the meta-analysis used olive oil as the placebo, thereby elevating the placebo effect to a whole new artform.

Also, as has been pointed out elsewhere, the statistical tools used to determine “no effect” in this meta-analysis may have been inappropriate and/or more rigorous than what’s typically used in similar analyses on drugs, diet, etc. Looking at the relative rate (RR) charts for all-cause mortality from consumption of omega-3 supplements (below), one can see a visible pattern for reduced risk of cardiovascular events through supplementation of omega-3 fatty acids. How much of a pattern (i.e., whether it is “significant”) depends on how you view the evidence.

(For perspective, statins, the poster children of modern medicine, continue to receive the acclaim of JAMA and physicians worldwide. This despite mixed results on the most relevant endpoint – mortality – including results from this recent study.)

Above: Risk of death from any cause associated with the use of statins (versus no statins) in patients at low cardiovascular risk, Tonelli et al, CMAJ. 2011 November 8; 183(16): e1189–e1202. Figure 2.

Maybe a more relevant question for interpreting this data remains: does a slight but relatively reliable reduction in mortality risk make a difference? Depends on what you define as a “difference.” Suppose there was no difference in results between treatment and placebo groups based on “Statistical Significance Using Methods Study Authors Used” (or SSUMSAU). But what if SSUMSAU is not the sole criteria by which we should be judging the worthiness of a study treatment? For example, a 1 percent reduction in the risk of dying due to taking fish oil regularly may not reach SSUMSAU – but is the prolonging of one life in 100 considered significant in another, more important way? 

In any case, although a cogent look at the science and statistics of this subject is outside the scope of this article, it is not difficult to see a reasonably strong pattern emerging from the omega-3 data. Based on this data, even the most science-minded among us are starting to get that eerie feeling that the big-pharma-conspiracy-theorists may be onto something.