Mitacek Eugene J, Brunnemann Klaus D, Suttajit Maitree, Caplan Lee S, Gagna Claude E, Bhothisuwan Kris, Siriamornpun Sirithon, Hummel Charles F, Ohshima Hiroshi, Roy Ranja, Martin Nimit
Department of Life Sciences, New York College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, New York 11568, USA.
Nutr Cancer. 2008;60(2):196-203. doi: 10.1080/01635580701649636.
It is our working hypothesis that the high rate of the liver and gastric cancers in North and Northeast Thailand is associated with increased daily dietary intake of nitrate, nitrite, and nitrosodimethylamine (NDMA). Samples of fresh and preserved Thai foods were systematically collected and analyzed from 1988 to 1996 and from 1998 to 2005. Consumption frequencies of various food items were determined on the basis of a dietary questionnaire given to 467 adults (212 males and 255 females) from 1998 to 2005. Food consumption data for the preceding and current year were collected and intakes (day, week, and month) of nitrate, nitrite, and NDMA were calculated. The trends in liver and stomach cancer age-standardized incidence rates (ASR) in four regions of Thailand were compared with the dietary intake of nitrate, nitrite, and NDMA in those same geographic regions. Mean daily intakes of nitrate of 155.7 mg/kg, of nitrite of 7.1 mg/kg, and of NDMA of 1.08 microg/kg per day were found. Significant differences in dietary nitrate, nitrite, and NDMA intakes were seen between various Thai regions (P < 0.0001), and these corresponded to the variations in liver and stomach cancer ASR values between the regions. Dietary factors are likely to play key roles in different stages of liver and stomach carcinogenesis in Thailand.
我们的工作假设是，泰国北部和东北部地区肝癌和胃癌的高发病率与日常饮食中硝酸盐、亚硝酸盐和亚硝基二甲胺（NDMA）摄入量的增加有关。1988年至1996年以及1998年至2005年期间，系统收集并分析了泰国新鲜和腌制食品的样本。根据1998年至2005年对467名成年人（212名男性和255名女性）进行的饮食问卷调查，确定了各类食品的消费频率。收集了上一年和当年的食物消费数据，并计算了硝酸盐、亚硝酸盐和NDMA的摄入量（每日、每周和每月）。将泰国四个地区肝癌和胃癌年龄标准化发病率（ASR）的趋势与这些相同地理区域内硝酸盐、亚硝酸盐和NDMA的饮食摄入量进行了比较。发现每日平均硝酸盐摄入量为155.7毫克/千克，亚硝酸盐摄入量为7.1毫克/千克，NDMA摄入量为1.08微克/千克。泰国不同地区之间的饮食硝酸盐、亚硝酸盐和NDMA摄入量存在显著差异（P < 0.0001），这些差异与各地区肝癌和胃癌ASR值的变化相对应。饮食因素可能在泰国肝癌和胃癌发生的不同阶段发挥关键作用。
