Supplements: how many do you take?
With heart health and increased brain function as two of its purported benefits, omega-3 is the most recent in a long line of supposed wonder supplements. With the omega-3 industry worth around £116 million, it seems the mantra ‘health is wealth’ couldn’t ring more true.
Found naturally in fish oils and many green leafy vegetables, omega-3 first appeared on the health food scene in the 1980s, after evidence that it could help prevent heart attacks and high blood pressure. Today, it has been heralded as an immune boosting, IQ raising and cancer fighting magic pill. However, two studies published in the Journal of the American Medical Association (JAMA) have cast doubt on the supplement.
Dr. Peter Kowey practices cardiology and internal medicine in Wynnewood, Pennsylvania. Along with several colleagues, he conducted a six-month trial with over 600 patients who suffered from an abnormal heart rhythm (arrhythmia). The trial was ‘placebo controlled’ which means that it included a group of patients who are received an inert, fake (often sugar filled) pill that looks and tastes identical to the real supplement. Neither doctors nor patients in the study know which pills are ‘real’. Thus, any physical improvements, which may be induced by the psychological expectations of getting better having had the pill—known as the placebo effect—which may also lead to physical improvements, are also considered.
“We began this study because there have been a number of previous studies carried out on these compounds that have had divergent results,” said Dr. Kowey. “It was pretty clear that they were safe, but their effectiveness was not really well established with regard to this particular arrhythmia.”
The results showed omega-3 to be ineffective, with no suggestion that the supplement prevented arrhythmia. Dr Kowey concluded that
“… the results for the non-placebo group were not substantially different to the placebo group.”
As if to twist the knife, the same volume of JAMA featured another study into the effects omega-3 had on Alzheimer’s sufferers, with equally poor results.
So why does omega-3 receive the glowing endorsement of nutritionists and glossy health magazines around the globe? There seems to be a long line of pill-poppers willing to testify about omega-3’s benefits. Catherine Morris is a 13-year-old student from Bedfordshire. After being diagnosed with attention deficit hyperactivity disorder (ADHD), Catherine’s father James suggested she took omega-3 to increase her concentration. “I really think it’s helped,” said James. “She seems more focussed, and her grades are on the up.
Increase in school performance is one of the major selling points of the pills, and is marketed mercilessly. Ben Goldacre, in his Guardian column Bad Science, has lambasted the so called ‘Oxford-Durham study’ which supposedly documented this increase in performance. 3000 students were given 6 pills a day to see if there was any improvement in their GCSE grades. Not only did the study fail to include a control (placebo) group, but the media circus surrounding the event cast significant doubt on its results. In addition, the study was sponsored by Equazen, the company which produced the pills used in the study, leading to accusations of a study geared towards getting positive results.
When it comes to treating depression, however, use of omega-3 shows real benefits. The largest ever study on the subject, published in the Journal of Clinical Psychiatry, shows a marked improvement in 432 patients suffering from depression. Research indicates there may be an association between a lack of omega-3 fatty acids and depressive disorders.
The jury is out when it comes to the all-round effectiveness of the supplement. Although Dr. Kowey assures me that “omega 3 is safe to take”, questions remain as to whether the supplement should be billed as such modern day cure-all, especially in light of the limited evidence behind it.
“There is a problem with supplements not going through a rigorous review process before they are put on the market.” Dr Kowey stresses. “We really end up not knowing what their efficacy is. Whether fish oil supplements work for the reasons people take them requires very careful clinical research.”
It is likely that omega-3 will continue to produce strong anecdotal evidence for certain health benefits, in conjunction with mixed clinical trials. This explains the sustained rise in popularity of the supplement, but until conclusive evidence is found, maybe it’s best to just stick to smoked salmon on toast.
Lespérance, F., Frasure-Smith, N., St-André, E., Turecki, G., Lespérance, P., & Wisniewski, S. (2010). The Efficacy of Omega-3 Supplementation for Major Depression The Journal of Clinical Psychiatry DOI: 10.4088/JCP.10m05966blu
Kowey PR, Reiffel JA, Ellenbogen KA, Naccarelli GV, & Pratt CM (2010). Efficacy and safety of prescription omega-3 fatty acids for the prevention of recurrent symptomatic atrial fibrillation: a randomized controlled trial. JAMA : the journal of the American Medical Association, 304 (21), 2363-72 PMID: 21078810
Logan, A. (2004). Omega-3 fatty acids and major depression: A primer for the mental health professional. Lipids in Health and Disease, 3 (1) DOI: 10.1186/1476-511X-3-25
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Mr Harris,
Would you be so kind as to link the research articles you refer to? E.g. the Japanese trial? May I also point out that the author, Richard Masters, produced this article on the basis of results published in well regarded and peer reviewed journals.
Perhaps you could point us in the direction of more recent studies which contradict what is being said here?
This is a very poor article which demonstrates only that complex biological mechanisms cannot be satisfactorily summarised by ill-informed authors writing short, glib comments.
There are a plethora of significant facts the author has failed to identify:
- Omega 3 oil supplements are manifold. Many, such as from ALA sources, are so poorly converted by the human body as to be virtually useless. Omega 3 supplements need to be in a natural EPA:DHA ratio sourced from clean water fish and ultra purified. Does the author know which oils the researchers used?
- Omega 3 fatty acids have seldom been valued for their anti-arrythmic properties. Atrial Fibrillation is a product of irritable foci within the heart; Omega 3 oils have rarely been cited as being efficient dietary adjuncts for the treatment of AF or any other supraventricular tachycardias. HOWEVER, Omega 3 oils have been scientifically proven to reduce cardiovascular disease of other origins. In particular a recent trial of Japanese heart attack patients found that secondary heart attacks were reduced by 40%!
There are a host of other scientifcally significant outcomes to support the daily intake of Omega 3 oils. Omega 3 isn’t a cure-all panacea, but it does have a place in the typically poor Western diet, particularly for those at risk of cardiovascular disease. Choosing the right oil is paramount however. The majority of those on the market will reduce nothing but the contents of your wallet.
Shame on the author for producing such a poorly researched and summarised article.
I find Omega-3 supplements is much safer to eat than cold-water fish which contains mercury.
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