New research shows diet and exercise may change how genes act

"These genes are the target of many new drugs that are being developed. Clearly, changing lifestyle is less expensive, and the only side-effects are good ones. Dr. Craig Venter’s pioneering research is showing that one way to change your genes is to synthesize new ones. Another may be to change your lifestyle."

This research have a very small sample size so it doesn't prove much but I found it very interesting.

clipped from news.google.com After their initial biopsy, we asked these men to make comprehensive lifestyle changes for three months.  These included a plant-based diet (predominant fruits, vegetables, legumes, soy products, and whole grains low in refined carbohydrates), moderate exercise (walking 30 minutes per day), stress management techniques (yoga-based stretching, breathing techniques, meditation, and guided imagery for one hour per day), and participating in a weekly one-hour support group.  After three months, we repeated the biopsy and looked at changes in normal tissue within the prostate.  We found that many disease-promoting genes (including those associated with cancer, heart disease, and inflammation) were downregulated or “turned off,” whereas protective, disease-preventing genes were upregulated or “turned on.”