Deadly Remedy

The dangers of herbal supplements were highlighted when a number of young women attending a weight loss clinic in Brussels, Belgium developed kidney failure. It turned out that the herb Aristolochia had been mistakenly substituted for another benign herb. Scientists linked the type of kidney damage found in the women in Brussels to a long-standing mysterious disease in the Balkans, referred to as Balkan Endemic Nephropathy. Studies using molecular techniques have shown that the cause of both conditions is a compound in the Aristolochia plant, which can cause kidney damage as well as a rare cancer of the upper urinary tract. This research underscores the dangers of certain herbal supplements.

When Risk Goes Viral

We are attuned to the latest potential threat to our health, and this creates a fertile soil for inflating the findings of observational studies. In fact, most reported findings are false or exaggerated. Nevertheless, such findings can be invoked by scientists, advocates, and health agencies to draw attention to a potential danger. Media reports of overstated findings can give rise to information cascades – highly-publicized campaigns that can sow needless alarm and lead to misguided regulation and policies.

The Illusion of Validity and the Power of “Negative Thinking”

Often our view of a problem is limited by our preconceptions, and we may fail to see other aspects that are crucial to its solution. This is true of attention to factors that may affect our health. There is widespread confusion about what are the real threats that can affect our health. On some issues, there is debate within the scientific community, whereas, on other issues, misconceptions are rampant in the wider society. These controversies can only be clarified by a critical assessment of the available scientific evidence, guarding against bias and preconceptions.

Hormonal Confusion

In the early 1990s concern emerged that hormonal compounds present in small amounts in food and water – “environmental estrogens” -- could be having subtle effects on human health and wildlife. This concern led to the formulation of the “endocrine-disruption hypothesis,” which has received widespread attention. Over twenty years of research have shown that environmental exposures to these substances is generally minute and are dwarfed by hormonal (phytoestrogenic) compounds in food, as well as by hormone therapy used by some women. Nevertheless, the issue of “endocrine-disrupting chemicals in the environment” is currently under debate within the European Union and elsewhere.

Do Cell Phones Cause Brain Cancer?

The possibility that using a cell phone could cause brain cancer first arose in the early 1990s and has been the subject of research since then. Radiofrequency waves used in cellular communications are far too weak to induce cancer by any known mechanism, and most scientific and regulatory bodies have found the evidence for health effects from use of mobile phones to be unconvincing. Nevertheless, positive results, largely from a single group of researchers, and an ambiguous assessment from single agency have kept the controversy alive. New studies are in progress.

Splendors and Miseries of Associations

Studies reporting associations between an exposure and a disease most often come from observational studies. These studies, while useful, cannot be taken at face value, and it is crucial to understand that “association” does not equate to “causation.” However, because it is challenging to identify important causes of complex chronic diseases, there is a tendency to latch on to findings that appear to point to a cause. If science in this area means anything, it means the uncompromisingly critical assessment of the relevant evidence bearing on a question.

HPV, Cancer, and Beyond

For over one hundred years, cervical cancer has presented a conundrum. In the 1960s and 1970s most virologists believed that herpes simplex virus-2 caused the disease. However, based clinical and animal evidence, the biologist Harald zur Hausen posited that human papillomaviruses (HPV) were the cause. It took him and his colleagues eleven years to prove that specific types of the virus were capable of causing cancer. This discovery led to a cascade of work elucidating the role of HPV in a number of cancers and, thirty years later, led to the development of the first vaccines to prevent infection with the virus.

Conclusion

In a pithy little book published in 2014 titled Are We All Scientific Experts Now?, the sociologist of science Harry Collins explored public attitudes toward science in an attempt to explain recent phenomena like the antivaccine movement and climate skepticism.1 Collins noted that the public’s trust in science has declined from its apogee in the decades following World War II, and he attributed this decline to a simplistic reading of Thomas Kuhn and the rise of social relativism, starting in the 1970s. He went on to provide a useful inventory of different types of expertise to distinguish what is special about ...