Do you enjoy a glass of wine from time to time? If so, were you alarmed to read headlines last fall announcing that ANY amount of alcohol is problematic? Here’s how those headlines came about. The researchers wrote in The Lancet (Sept. 22, 2018), in their interpretation of their meta-analysis of the health risks, world-wide, of alcohol consumption:
“the level of consumption that minimises health loss is zero.”
Obviously, people who consume excessive amounts of alcohol are putting their health at risk. But maybe those who drink only occasionally don’t need to freak out. Dr. Aaron Carroll, pediatrician and research mentor, explains just why. You can read his article in The New York Times Upshot, but you should also listen to our interview. In it, he explains the basic statistics you need in order to understand this and similar research and make choices about which health risks you should worry about.
Part of the problem is due to the study methodology. Observational studies may find associations that don't have a causal connection. But part of the problem may also be due to how studies are presented in the media. Exciting findings make good headlines. Negative results may be good science, but they don't attract attention.
Nutritional studies have been especially prone to flip-flops. One month you may read that coffee is bad for your heart; the next month you might read that it will protect you from heart failure and help you live longer. At one time, Americans were advised to avoid eggs if they wanted to be healthy, but more recent data have exonerated eggs, even for people with diabetes.
Dr. Carroll has pointed out the weaknesses of research design in a study that claimed kids eat more fruit if the apples are decorated with cartoon characters. Why was this study retracted? And how, really, can you get kids to make healthier food choices?
All drugs are supposed to be safe and effective, but how exactly do we define safe and effective? Research design also has an impact on the medications that FDA approves for use, such as antidepressants. What do you need to know about the benefits and harms of the drugs you take? How can you figure out if an article is describing absolute risk or relative risk–and relative to what? This is crucial in evaluating which health risks you should worry about.
You can teach old dogs new tricks; the trouble is in teaching them to give up their previous tricks. The same is true for all of us, including doctors. As a result, the doctor may recommend a treatment that is no longer state-of-the-art. It may even have been shown to be inappropriate in most cases. However, if ear tubes, for example, are what a pediatrician has been recommending for decades, he or she may continue to recommend them. How does this impact you and your children?
Dr. Aaron Carroll is a Professor of Pediatrics and Associate Dean for Research Mentoring at Indiana University’s School of Medicine, and Director of the Center for Pediatric and Adolescent Comparative Effectiveness Research. His research focuses on the study of information technology to improve pediatric care, health care policy, and health care reform. In addition to his scholarly activities, he has written about health, research, and policy for CNN, Bloomberg News, the JAMA Forum, and the Wall Street Journal.
He has co-authored three popular books debunking medical myths, has a popular YouTube show called Healthcare Triage, and is a regular contributor to the New York Times’ The Upshot. Dr. Carroll’s most recent book is The Bad Food Bible: How and Why to Eat Sinfully. The photograph of Dr. Carroll is copyrighted by Marina Waters.