Genes Are Only Part of the Story

I discussed this with Dr. James Hill, director of the Center for Human Nutrition at the University of Colorado Health Sciences Center. "Telling people it's all in their genes is a devastating message," he said. "There are a few rare individuals in whom genes are just so bad that the amount of work to maintain a healthy weight is not feasible. But for most people, their genes allow them to maintain a healthy weight if they're willing to make sufficient changes in diet and lifestyle. Some have to work harder than others, and exercise becomes even more important for those who are genetically disadvantaged."

According to Ryan Phelan, founder and CEO of DNA Direct (a company that offers genetic testing), "It's about putting your genes in context, in perspective—your overall health with the conditions within which you live, including stress, the environment, all of the other lifestyle factors. It's important not to overstate the role of genetics. My hope is that this is really the beginning of personalized medicine for the masses. It's crazy the way our health-care system has had to treat us all like we're one and the same person. We're all completely unique. We respond differently to diet, we respond differently to medications—and some small part of that, some people say as much as 20 percent—can be linked to our genetic differences. So to me the challenge is to find where that genetic variance is—to help people use it as a motivational factor—not as a deterrent."

To be responsible is not to blame ourselves, it's to empower us. If we're just victims of our bad genes, or bad karma, bad fate or bad luck, then there's not much we can do about it other than to suffer our destiny. But to the degree we realize that we can do something about it, then we're free to change our fortune. These new genetic discoveries can help us understand how much we might need to change in order to accomplish our goals and to stay healthy and feeling good. How much you want to change your diet and lifestyle—if at all—is a very personal decision.

While there is a genetic predisposition to chronic diseases such as coronary heart disease, diabetes and obesity—and, in all likelihood, to many other illnesses as well—in almost all cases, it is just a predisposition, not a death sentence. For example, even if your mother and father and sister and brother and aunts and uncles died from coronary heart disease, it doesn't mean that you ever need to. However, it probably means that you have to make bigger changes in diet and lifestyle than someone who has better genes.

According to Dr. David Heber, director, UCLA Center for Human Nutrition, "Genes load the gun, but environment pulls the trigger. The idea that it's all in your genes is nonsense. The human genome changes only one half of one percent every million years. The obesity epidemic is only about 30 years old, so changes in genes do not explain the recent dramatic rise in obesity, not only in this country but also worldwide."

During the past 30 years, my colleagues and I at the nonprofit Preventive Medicine Research Institute conducted a series of randomized controlled trials and demonstration projects proving, for the first time, that the progression of coronary heart disease may be reversed by making comprehensive changes in diet and lifestyle.