I have been very hesitant about embracing genetic testing because I really don’t want to know about my inherited risk of getting Alzheimer’s disease since no treatment is currently available. However, a new study from Stanford University that focuses on the genetic aspect of weight loss has me rethinking whether this testing would be beneficial at some point.
The study, reported in the Wall Street Journal , found that a genetic test may determine the type of diet that will help people lose weight. The study followed 133 overweight women for a year. Dr. Christopher Gardner, an associate professor of medicine at Stanford and co-author of the study, and his team of researchers found that identifying an individual’s genetic predisposition to either a low-fat diet or a low-carb diet may result in greater weight loss. The study found that those women who were determined to genetically benefit from a low-carb diet lost 2-1/2 times more weight than those who were on the same diet, but who didn’t have that predisposition. The researchers’ findings also had strong statistical significance, which means that the findings are not likely to be due to chance.
These 133 women were part of the A to Z study, which involves 301 participants in a research project to determine the effects of four weight-loss diets – the Learn and Ornish diets (which are low-fat diets) and the Atkins and Zone diets (which are low-carb diets). In the A to Z study, the Atkins diet was found to be slightly more effective with participants However, the impact of the diet varied within each diet group, with some participants losing more than 30 pounds and others gaining weight. Researchers hypothesize that genetics may explain these differences.
Some scientists question the findings and caution about running out to purchase a genetic test. The Associated Press quotes Raymond Rodriguez, the director of the National Center of Excellence for Nutritional Genomics at the University of California-Davis, as saying, "I have serious reservations with this study and studies like it. The idea that genetic variants in these genes can predict the likelihood for weight loss in such a small population, particularly since the tendency for weight loss is probably more behavioral than genetic, is simply hard to believe."
Food choices still will be a factor, even if you know that your genetic propensity focuses your weight-loss efforts on one particular diet. The Wall Street Journal write-up noted, “Just matching the right diet with your genes doesn’t guarantee significant weight loss for everyone, Dr. Gardner cautioned. If low-carb people make a diet out of low-carb cupcakes, he said, they’re unlikely to see the results they want on a scale.” And although the Associated Press and Wall Street Journal articles don’t address it, exercise is another key component in weight loss.
This coverage also showcases how scientists are studying the link between the foods we put into our mouths and our genetics. For instance, The Times of India reports that Kansas State University researchers believe that diets eventually will be tailored to each individual’s genetic makeup. The researchers are working in the new field of nutrigenomics, which focuses on molecular biology, genetics and nutrition in an effort to regulate gene expression. As part of their work, the scientists are studying specific foods’ relationships to disease; this would enable dietary recommendations to be tailored to each individual based on his or her genetics.
Although I’m not quite ready to go purchase a genetic test yet, I am going to keep watching these studies because I do think it makes sense that each individual’s body utilizes specific foods differently. Hopefully scientists will be successful in discovering those genetic traits and the food groups that will not only allow us to maintain a healthy weight, but also to fighting off diseases (such as Alzheimer’s) that may be encoded in our genes.
Published On: March 31, 2010