[ti:Study: Vitamin Supplements May Harm Breast Cancer Treatment] [by:www.51星和彩票.com] [00:00.00]更多听力请访问51VOA.COM [00:00.04]A new study suggests that patients with breast cancer who take additional vitamins [00:07.44]during chemotherapy treatment may face increased risks. [00:14.44]Researchers said the use of dietary supplements that increase levels of antioxidants, iron, [00:23.96]vitamin B12 and omega-3 fatty acids appeared to lower the effectiveness of chemotherapy. [00:35.56]Researchers reported their findings in the Journal of Clinical Oncology. [00:44.00]Christine Ambrosone is the head of cancer prevention and control [00:50.12]at the Roswell Park Comprehensive Cancer Center in Buffalo, New York. [00:57.92]She said, "From this study and others in the literature, [01:02.52]it seems that it may not be wise to take supplements during chemotherapy." [01:11.04]"It's thought that antioxidants might interfere with the ability of chemotherapy to kill cancer cells," Ambrosone said. [01:24.12]Some doctors have been advising patients for a number of years [01:30.00]not to take antioxidants during chemotherapy. " [01:35.92]But there was no strong empirical data for that recommendation," Ambrosone said. [01:45.80]So, Ambrosone and other researchers decided to study [01:52.16]whether supplement use might affect chemotherapy's effectiveness. [01:59.84]They looked for evidence in an earlier study on diet, exercise, lifestyle and cancer results. [02:10.96]In the earlier research, people who took part were asked about their use of supplements [02:18.76]at the beginning of and during treatment, and about their lifestyle, diet and exercise. [02:29.20]The researchers studied 1,134 patients who filled out the surveys and followed them for a median of six years. [02:44.08]Their supplement use was much lower than usual, Ambrosone said. [02:51.64]About 20 percent of patients were taking supplements [02:56.60]before starting chemotherapy and 13 percent during the treatments. [03:05.84]The researchers searched for other possibilities that might increase the risk of the disease reappearing or of death. [03:19.32]They found that patients who took any supplements at the beginning of and during chemotherapy [03:27.76]were 41 percent more likely to have their breast cancer return than those who did not. [03:38.08]In addition, the supplement takers were 40 percent more likely to die later on [03:45.72]compared to patients using no supplements. [03:51.16]The supplements included vitamin A, C and E. [03:58.04]Those taking vitamin B12 and iron supplements were at greater risk of cancer returning, the researchers said. [04:09.92]Women taking vitamin B12 were 83 percent more likely to experience a return of their disease [04:20.68]and 22 percent more likely to die from it than those not taking those supplements. [04:30.88]Those taking omega-3 supplements were 67 percent more likely to have the disease return. [04:41.60]That percentage rose to 79 for those taking iron supplements. [04:49.80]Amy Tiersten is a professor of medicine at the Icahn School of Medicine at Mount Sinai in New York City. [05:01.52]She said she was pleased with the research. [05:06.76]"For years we have been cautioning patients about the use of vitamins, [05:13.20]in particular antioxidants, during chemotherapy for breast cancer," Tiersten said. [05:23.28]In an email to Reuters news service, she said that she "always told patients on chemotherapy [05:32.48]that the best way to get their vitamins is through a well-balanced diet, [05:39.16]and will continue to do so given these data." [05:46.24]I'm Mario Ritter, Jr. 更多听力请访问51VOA.COM