TMC PULSE

t m c » p u l s e | n o v e m b e r 2 0 1 6 15 W hen bariatric surgeon Garth Davis was 35 years old, he took a health screening for a life insurance policy. The results were anything but positive. "I didn't think I was unhealthy, but my cholesterol was through the roof, I was hyper- tensive and I had a fatty liver," Davis said. "Shocked, I went to see an internal medicine friend of mine, and he told me I could take all of these medicines for my problems, but I knew that would just lead to more and more medi- cine throughout my life." Davis, the medical director of the Bariatric Surgery Program at Memorial Hermann Memorial City Medical Center, didn't want to be medicated for the rest of his life. So he went looking for some answers. He discovered that the United States is one of the least healthy countries in the world and that Americans have some of the lowest life expectancies on the planet. So which countries were healthy, Davis wondered, and how did they get that way? His research led him to author Dan Buettner's Blue Zones study on the world's happiest and longest-living cultures. One of the things these cultures had in common was diets based mainly on plants and carbohydrates. "I was kind of surprised because I had been telling all of my patients not to eat carbs, and I had purposefully avoided them myself," said Davis, also an assistant professor of surgery with McGovern Medical School at UTHealth and a member of UT Physicians. Particularly inspiring to Davis were the Okinawans of Japan, who live an average of 10 to 15 years longer than Americans. Staples of their diet include low-calorie seaweed and yams. Davis was also fascinated by the Seventh-Day Adventists of Loma Linda, Calif., a religious group that mixes spirituality with healthy living. They consume a lot of beans, soy milk and tomatoes, shown to help reduce the risk of certain cancers and heart disease. Davis also considered the European Prospective Investigation into Cancer and Nutrition (EPIC) study, jointly coordinated by Imperial College London and the International Agency for Research on Cancer in Lyon, France. The study followed some 370,000 men and women in 10 European countries for five years and found that meat consumption was linked to weight gain—even chicken, one of the lean proteins Davis often recommended to his patients. "It got me thinking that maybe everything I was told before was completely wrong," Davis said. The ultimate irony for Davis: As a bariatric surgeon, he performs surgery on the stomach and intestines of patients to induce weight loss. His work addresses the effects of a poor diet. But what about the causes? What if he could catch patients before bariatric surgery was necessary? Or at least teach his patients how to eat healthier after their surgeries? No simple magic bullet Humans have always used plants to treat illness and disease. Many of our most common med- icines come from plant extracts or synthetic plant compounds. Aspirin is derived from willow bark. Quinine, which is used to treat malaria, comes from the bark of the cinchona tree. Muscle creams, cold medicines and lozenges often contain mint. Today, diet plays a key role in plant-based medicine, a growing industry made popu- lar by people craving healthier lifestyles. The dietary supplements business earns $37 billion a year, according to the National Institutes of Health, and $5.7 billion of that is spent on multivitamins. But there is a lot of misinformation out there about what eating certain plants can and cannot do, said Roderick Dashwood, Ph.D., director of the Center for Epigenetics & Disease Prevention in the Institute of Biosciences and Technology at Texas A&M University. Some people expect a "simple magic bullet," and are disappointed when they don't get the results they anticipated. Dashwood is researching how phyto- chemicals—chemical compounds that occur naturally in fruits, vegetables, grains and other plant foods—have been linked to reduction in the risk of major chronic diseases. Some researchers have even created genetically engineered plants with increased levels of a certain phytochemical. Organizations including the National Institutes of Health and the American Cancer Society generally recommend that people consume five to nine servings of fruits and vegetables per day, Dashwood said. But he was intrigued by an American Institute of Cancer Research study that asked: "What if people actually followed that recommendation? Would it really show a benefit?" "They found out that yes, indeed it does," Dashwood said. "If you switched from a bad diet to one of these improved diets, there was reduction in certain cancers. However, people improving their diets also did other things like quit smoking, limit their alcohol intake and get on the treadmill for the first time at the gym. So it is hard to say it was just the plant- based diet." It got me thinking that maybe everything I was told before was completely wrong. — GARTH DAVIS, M.D. Medical Director of the Bariatric Surgery Program at Memorial Hermann Memorial City Medical Center; Assistant Professor of Surgery with McGovern Medical School at UTHealth; a member of UT Physicians

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