Remember the song “it ain’t necessarily so…”? – The lyricist must have been pondering the process of publishing scientific health research when he wrote it. At least, that old tune was playing in my head recently when I was alerted to a disconcerting media article about omega-3 oils. The news report would have alarmed anyone who hadn’t reviewed the original paper. So I’d like to pass on to you some skills for assessing the value of health ‘news’ that you read, particularly when it’s about published research, so you don’t become unduly alarmed by a dysfunctional research conclusion.
There are three types of health research that appear regularly in the media: Firstly, epidemiological studies, which review hundreds or thousands of people over many years, and collate statistics from that data; For example, an epidemiological study about omega-3 oils might extract data about the health outcomes for people who have been taking fish oil supplements for many years, and present statistics that summarise the health benefits or dangers of that supplement. Epidemiological studies are great for overviews, but can include so many people that individual factors are buried.
Clinical trials, the second type of research, are smaller studies of a relative handful of people, usually examining a specific subject or therapy; like research on omega-3 oils which examines the usefulness of omega-3 oils as therapy for people with joint problems. Traps in clinical research that result in a mistaken conclusion can be poor study design, or use of an inappropriate dose, or the wrong species of plant. (The latter pitfall frequently occurs in research about the efficacy of certain herbs)
Reviews, the third type you’re likely to come across, summarise research already published on one subject. A literature review or meta-review of studies on omega-3 oils, for example, will collate and summarise research by other scientists over the past few years. Flawed conclusions can emerge here because the writer may have chosen to include research that supports his theories, and exclude any other findings.
In all of these cases, the wrong conclusion can easily be reached, and sometimes you have to carefully comb through the original research to uncover the methodological flaws that led to the inappropriate conclusion. Not many of us have the time or resources to do that. In the meantime, you could have read a media interpretation of this defective research that is alarming. We all tend to believe what we see printed, at least initially; but it turns out that not all scientific research is worthwhile.
When you encounter an alarming report, especially when it relates to a food you eat or supplement you take, a useful first step is to search for the research on Google Scholar, then read the ‘abstract’ (that’s the summary). Rather than abandon your supplements, or change your diet radically, clip the article and discuss it with your health practitioner. They’ll help you work out whether the research findings are valid and whether your treatment should be altered as a result.