There’s never a dull moment in the business of interpreting science for the public. Each day seems to bring an onslaught of fresh scientific studies that pertain to virtually every aspect of our life. I look forward to wading through these, but it is increasingly challenging to avoid drowning in the data. Information overload is a vexing problem! For me, the real difficulty lies in trying to distil some practical sense out of the flood of research findings. I can certainly appreciate the journalistic temptation to come up with seductive headlines for stories, but my concern is that often these oversimplify the results of published research, and, in the end, they either provoke unnecessary fears or raise unrealistic hopes. As Mark Twain quipped, “There is something fascinating about science. One gets such wholesale returns of conjecture out of such a trifling investment of fact.”
Take, for example, a paper that appeared in the Journal of Agricultural and Food Chemistry entitled “Which Polyphenolic Compounds Contribute to the Total Antioxidant Activities of an Apple?” Because apples are dear to our hearts, and “anti oxidants” have a positive public image, it wasn’t surprising that the press reported widely on the results of the research with headlines such as “Red Delicious Best Disease Fighter.” The impact was noted almost immediately with increased sales of Red Delicious apples. Now, I have nothing against these apples; in fact, I like them. But this study did not show that they fight disease better than other apples! To do that, you would have to follow two groups of subjects for many years, with one group regularly eating Red Delicious apples, the other eating some other variety. What the study did show was that Red Delicious apples have a higher level of antioxidants than some other apples, although varieties such as Jonagold, which is known to be high in antioxidants, were not included. I think we can safely say that fruits are good for us, and that at least part of the benefit likely comes from their antioxidant content. However, it is unrealistic to imply, based on this apple antioxidant study, that substituting Red Delicious apples for others is going to have an impact on overall health. This difference in antioxidant content, relative to the total amount of antioxidants we consume, is not likely to be of practical significance. By all means eat apples—of any variety, along with loads of other fruits and vegetables—but don’t assume that Red Delicious apples have some special magical quality. No food does.
So what do we say to breast cancer patients who have read about a study carried out at the University of Texas M. D. Anderson Cancer Center that suggests turmeric, the yellow spice widely used in Indian cuisine, may help stop the spread of breast cancer? First, let’s take a look at what the researchers actually did. Based on earlier studies that showed a lower rate of cancer in people who had a diet rich in turmeric, and some previous evidence that one of its ingredients, curcumin, had an anti-tumor effect in the laboratory, the scientists decided to investigate curcumin’s anti-cancer potential in a living species. They produced tumors in mice by injecting them with human breast cancer cells, and then surgically removed the cells to mimic a mastectomy. Some of the animals received no further treatment; some were treated with curcumin, some with the cancer drug paclitaxel (Taxol), and others with a combo of curcumin and paclitaxel. The curcumin clearly had an effect: 95 percent of the untreated animals went on to develop lung cancer, but only 50 percent of those treated with curcumin developed tumors. When combined with paclitaxel, the results were even better, with only 22 percent of the mice showing lung tumors. But what does this mean in human terms? Again, it would be unrealistic to suggest that eating curry prevents the spread of cancer. Nobody knows how effectively curcumin is absorbed from the digestive tract, or if it actually has an effect in humans. How much curry would we have to eat? Nobody knows. What we can say is that, based on such studies, it is time to carry out a human trial. Labeling turmeric as an anti-cancer spice is premature and may give false hope.
Putting scientific studies into perspective is now more important than ever because we are on the verge of suffering from health and safety advice overload. As study piles upon study— often with apparently contradictory findings—many people are throwing their arms up in frustration. One study shows that Echinacea may help the common cold; another says it’s practically useless. Depending on which study you read, vitamin E is good for almost anything that ails you, or is totally ineffective. In fact, it may even be harmful. Coffee may raise your blood pressure according to one report, while another one finds that it is the number one source of antioxidants in the North American diet. The consequence may be that consumers stop listening to any advice. That’s why it is important to emphasize that science is based on a continuous evaluation of all studies until a consensus is reached, and that making lifestyle decisions based on any individual study is rarely warranted. Especially if you believe Dr. John Ioannidis, an epidemiologist at the University of Ioannina School of Medicine in Greece, whose paper in the Journal of the American Medical Association claims that there is less than a 50 percent chance that the results of any randomly chosen scientific paper are reliable. His analysis suggests that, due to problems with experimental and statistical methods, small sample sizes, researcher bias, and selective reporting, most research findings cannot be trusted. I suppose this includes his findings as well.
Isaac Asimov, the famed science writer, put it very well when he noted that science now gathers knowledge faster than society gathers wisdom. Let’s see what we can do about gathering knowledge and interpreting it with wisdom. And you know what? Eating flax may help us do just that. At least one study claims flax can increase mental prowess. But of course, the study could be wrong.