TMC PULSE

t m c » p u l s e | n o v e m b e r 2 0 1 6 17 that had already been picked could be retrained to produce insect- repelling phyto- chemicals. They found that the circadian clock of the vegetables, which is affected by light and tem- perature, could cause the vegeta- bles to produce more or less of the phytochemical depending on the time of day. "Our research showed it could make sense to eat the cabbage in the middle of the day when we found that the phytochemicals implicated in anti-cancer efforts were the most abundant," Braam said. After working with cabbage, the team decided to try their technique on other fruits and vegetables, includ- ing spinach, lettuce, zucchini, sweet potatoes, blueberries and carrots. All of them were able to show time- dependent changes similar to the cab- bage, Braam said. Her team is still working to determine the optimal time to eat fruits and vegetables. But Braam thinks this type of research could help food producers target the peak time to freeze or preserve certain plants—to capture them when their health-active compounds are most potent. "Plants have the potential for providing health-active compounds that could affect cer- tain diseases, but whether the plant circadian clock is enough to have a big health or nutri- tional impact, we don't know yet," she said. Beautiful bowls of lentils Cruciferous vegetables also played a key role in a 2015 study by Dashwood and his colleagues, including Praveen Rajendran, Ph.D., an assistant professor in the Institute of Biosciences and Technology at Texas A&M. Published in Clinical Epigenetics, the study asked whether sulforaphane—a type of phytochemical—helped to reduce indicators of cancer risk. Sulforaphane occurs naturally in broccoli and other cruciferous vegetables such as Brussels sprouts, kale, cauliflower and cabbage. To conduct their research, Dashwood and Rajendran asked patients scheduled for routine colonoscopies to complete a detailed food questionnaire. Those that ate more servings of cruciferous vegetables were shown to have higher expression levels of a tumor suppressor gene called p16 than those who ate few or no servings. Dashwood and Rajendran also found that the p16 enhance- ment benefits continued even after the vegetables were not consumed every day. "Our research hints at the possibility that epigenetic mecha- nisms (how genes are read by cells) are initially triggered by sulforaphane and could be sus- tained, at least in the short- term, even after compounds are elim- inated from the body," Rajendran said. Though further research is needed, Rajendran said an effective broccoli pill or supplement may help prevent tumor growth. In the meantime, individuals who follow nutrient-rich plant-based diets enjoy prolonged health benefits. Dr. Garth Davis has maintained his plant-based diet for a decade. He didn't just drop meat cold turkey, but reduced con- sumption gradually over time. Today, both his cholesterol and blood pressure are normal, and he no longer has a fatty liver. Davis also stopped using the word "pro- tein" when discussing food plans with patients. Instead he pitches beans, grains, fruits and vegetables, something that has revolutionized his medical practice, he said. Through social media, support meetings, tips for success, nutrition education and tasty recipes, Davis helps patients and the community with health- ier choices. People tell Davis he must have great willpower to avoid meat, but he says willpower has nothing to do with it. He just likes the way he feels. He craves fruits and vegetables, and the thought of eating cheeseburgers—his former favorite food—actually repulses him. "I'm not out to create new vegetarians or vegans, just better plates for my patients," Davis said. "We have grown up where animal protein is the center of the meal, but now I eat beautiful bowls of lentils and yams and vegetables, and it tastes great." E ating well doesn't just help fight disease. It helps the body perform. Healthy people have close to 500 species of bacteria living in harmony in their stomachs. Problems occur when that harmony is disrupted, either by genetics or the wrong food, says Jeff Tabor, Ph.D., assistant professor of bioengineer- ing at Rice University. Disruption can cause inflammation, which could lead to intestinal issues such as Crohn's disease or diverticulitis. Eating probiotics—live micro- organisms commonly found in yogurt and other dairy products— has been widely shown to help remedy the disruption in gut bacte- ria and stimulate the growth of good bacteria. "Certain foods encourage the growth of good bacteria," Tabor said. "For example, plants have fiber, like those long, stringy parts of celery. We can't break that fiber down, but the good gut bacteria can, and can then make beneficial molecules that are important to us." Tabor wants to engineer diag- nostic gut bacteria. That way, if a doctor suspects a problem, a patient could take a drink home that would produce a visible blue pigment in his or her stool. In just one day, the doctor would know if additional tests were needed. G O O D BACTER I A

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