That Personal Touch
- That Personal Touch
To the Editor: Last year I sent a vial of my spit to a prominent direct-to-consumer genetic testing company. The company's Web site promised that, in return, I would get genetic risk information that would allow me to "make life-style choices" and "make more informed decisions" about my health—in other words, personalize my health behaviors and medical care.
When the results arrived I found little that was helpful. There was lots of fun and interesting information. It was, after all, information about me—one of my absolute favorite topics. And the data were presented in a sophisticated and engaging manner that made them easy to understand. But was there any information that should or would nudge me toward adopting a unique and personalized preventive strategy? Not really.
Susan Gilbert's essay ("Personalized Cancer Care in an Age of Anxiety," Sept-Oct 2010) reminds us that even in the area of targeted cancer therapies, one of the most promising applications of genetic technologies, complex questions of utility and long-term benefit remain. But genetic information is supposed to help us do more than just treat disease. Indeed, it has long been suggested that the prevention of disease, not just personalized clinical treatment, will be one of the primary benefits of the "genetic revolution." Yet just as the use of genetic information in the clinical setting poses profound challenges—a theme of several of the essays in this volume—there are also tremendous limitations to the utility of this information as a tool for prevention.
Just a few weeks before writing this commentary, I received an update e-mail from my testing company that contained some new genetic risk information. It turns out that I am at a slightly increased risk for colorectal cancer. The average lifetime risk for individuals of European ancestry is 5.6 out of 100, and my risk is 7.7 out of 100. Here is the lifestyle advice that accompanied the risk information I received: exercise, keep my weight down, drink only moderate amounts of alcohol, and eat fruits, vegetables, and whole grains.
Solid advice. But this is how we should live regardless of our genetic risk. And we all know (or should know) these simple, bedrock strategies to reduce the risk of common chronic diseases. The problem, of course, is that very few individuals live this way. Actually, to be more precise, almost nobody lives this way. A study exploring the eating habits of the American population published in the September 2010 issue of Journal of Nutrition found that "nearly the entire U.S. population consumes a diet that is not on par with [national] recommendations." In other words, no one in the United States is eating a healthy diet. Another study, published in 2010 in the American Journal of Preventive Medicine, found similarly depressing figures for exercise. Only 5 percent of Americans get any vigorous exercise. The most commonly reported moderate "exercise"? Food preparation.
These studies paint a grim picture—one that is supported by many other studies. And they remind us that from the perspective of public health, worrying about personalizing our preventive strategies based on genetic risk information borders on the absurd. When no one eats a healthy diet, few get sufficient exercise, over a third of the population is clinically obese, and many still smoke, we should not pay too much attention to tiny increases in genetic risk for common diseases. Let's start with the basics. Eat your broccoli, take the stairs, and don't worry about whether you have a 5.6 percent or 7.7 percent lifetime risk for a grave disease because either way, a sensible lifestyle is the healthy choice.
- To the Editor
Personalized medicine is not a new idea. Physicians already take into consideration a patient's personal situation (age, gender, weight, personal and family history, presence of risk factors, diet, and medications, for example) when selecting or adjusting a course of treatment. Screening tests have been used for decades to identify high-risk groups who could benefit from specific surveillance or different management. But the term "personalized...
