You’ve probably heard the crack about journalistic priorities: “if it bleeds, it leads”.
Consumers can blame themselves, because they reward bringers of bad news with bigger circulations and ratings.
However, when it comes to nutrition-health research, the reward media outlets get for slanting their coverage toward negative news presents a distorted picture.
The media was quick to report on a non-credible claim that omega-3s are linked to prostate cancer risk, which was quickly debunked by experts in the field ... see “Fishy Prostate News” and “Can Prostate Cancer be Curbed by Omega-3s?”.
And it’s always been eager to report studies seeming to show that omega-3s don’t do much for heart health.
For example, many news headlines trumpeted the disappointing results of one recent study, but ignored the greater number of positive studies and the positive findings within the “negative” study … see “Does Fish Oil Really Help Hearts?”.
A new review of the evidence regarding omega-3s and blood pressure offers more proof that media outlets don’t like to accentuate (or even acknowledge) the positive.
This study was larger and more comprehensive than any preceding evidence review, and it drew positive conclusions … good news that apparently didn’t interest editors. Omega-3s and blood pressure: The background
For decades, evidence that fish and omega-3s reduce blood pressure has been accumulating.
This is no small matter, since six out of 10 American adults suffers from hypertension, which promotes cardiovascular disease and dementia.
And all of the evidence reviews published in the past 20 years have upheld that hypothesis (Appel LJ et al. 1993; Morris MC et al. 1993; Mori TA et al. 1999; Cicero AF et al. 2009; Cicero AF et al. 2010; Mori TA 2010)
We’ve reported on a few related studies … see “Omega-3s Cut Blood Pressure in Hefty Teens”, “Prawn Proteins Eased Blood Pressure”, and “Two Omega-3s Better than One”.
In contrast, conventional wisdom regarding sodium has been crumbling … see “Salt Exonerated (Mostly) by U.S. Experts”, “Salt Intake Set by the Brain”, and “U.S. Salt Advice: Best Take it with a Grain.
So it’s sad that the media ignored the positive conclusions reached by the authors of the largest evidence review to date.
Evidence review: Omega-3s drop blood pressure substantially
The new meta-analysis (reviews of studies) covered 70 randomized controlled clinical trials, including the substantial number published in the past two years (Miller PE et al. 2014).
The objective was to examine the blood pressure effects of seafood-source omega-3s (EPA and DHA), from supplements and fish.
And the results confirm that omega-3 EPA and DHA are as or more effective than the three most commonly advised lifestyle changes: increased exercise and reduced alcohol and sodium intake.
The study examined 70 randomized controlled trials in adults who were given EPA+DHA omega-3s from seafood, fortified foods, or dietary supplements.
It included trials with subjects with normal blood pressure and those with hypertension who were not taking blood pressure-lowering drugs.
The most significant benefits were seen in people with high blood pressure, in whom omega-3s dropped systolic blood pressure (SBP) by an average of 4.51 mm Hg and diastolic blood pressure (DBP) by an average 3.05 mm Hg.
Additional findings included these effects of seafood and seafood-source omega-3s:
- An average decline in SBP of 1.52 mm Hg and in DBP of 0.99 mm Hg among all subjects
- An average SBP drop of 1.25 mm Hg and DBP drop of 0.62 mm Hg in people with normal blood pressure
- An average SBP drop of 1.75 mm Hg and in DBP drop of 1.11 mm Hg among people taking fish oil, regardless of blood pressure status
The findings were even more dramatic when compared with reductions achieved through commonly recommended lifestyle changes, as indicated in the chart below:
Small but highly significant results
“When measuring blood pressure, even small reductions can have a significant clinical impact,” said Dominik D. Alexander, PhD, MSPH, senior author of the study.
Every 2 mm Hg reduction reduces stroke mortality by 6 percent, coronary heart disease mortality by four percent and total mortality by 3 percent (Stamler R 1991).
Alexander noted that a decrease in SBP of 1.25 mm Hg could prevent a pre-hypertensive from becoming hypertensive.
“A decrease of 4.51 mm Hg in SBP among those with high blood pressure could help an individual avoid having to take medication to control blood pressure levels,” he added.
So the next time you see a report on negative research regarding omega-3s (or any other food or natural product) remember the media’s bias toward the negative!
The study was funded by the Global Organization for EPA and DHA Omega-3s (GOED), which submitted an authorized health claim petition to the FDA based on these results.
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