Studies on Biochemical Indicators of Dietary Intake

我们的研究对象是长野、大坂、鸟取和冲绳的242名健康居民（121名男性和121名女性），年龄从30岁到60岁不等。为了评价13种血液生化指标，我们在一年的时间间隔内采集了两份血液样本。这些生化指标被认为是显示个人的饮食摄入水平。在此基础上，我们对他们进行了为期16天的称重记录膳食调查，即一年中每个季节4天，计算了他们膳食中营养素摄入量的年平均值，并计算了上述生化指标在一年内的Pearson相关系数。维生素的相关系数为0.3 ~ 0.5，胆固醇的相关系数约为0.8。它们具有统计学意义。此外，我们还计算了膳食营养素摄入量与血液生化指标的相关系数。维生素E、维生素B_6、维生素6_1<12>、叶酸和维生素C的相关系数在0.18 ~ 0.35之间。女性高于男性，推测吸烟可能降低了血液中维生素C的浓度，因此，我们认为，将血液中维生素C作为生化指标，将指示短期（约2周）或长期（约1年）的饮食摄入量。

We targeted 242 healthy residents(121 male and 121 female) of Nagano, Osaka, Tottori and Okinawa, ranging in age from 30 to 60 for our research. In order to assess 13 kinds of biochemical markers in blood, we obtained their two blood samples at a one-year interval. These biochemical markers were considered to show the individuals' dietary intake level. Furthermore, we conducted weighing record dietary survey with them for a total of 16 days, that is, four days each season during one year and computed the annual means of the nutrients in their dietary intake.We computed the Pearson correlation coefficient of the above-mentioned biochemical markers at a one-year interval. The correlation coefficients of vitamins were from 0.3 to 0.5, and those of cholesterol approximately 0.8. They were statistically significant. These results confirmed the high reproducibility of biochemical markers.In addition, we computed the correlation coefficients of dietary nutrient intakes and biochemical markers in blood. The correlation coefficients of Vitamin E,Vitamin B_6,Vitamin 6_<12>,folic acid and Vitamin C showed the range from 0.18 to 0.35.Furthermore, with respect to the correlation coefficients of dietary Vitamin C intake and Vitamin C concentration in blood, the females were found higher than the males.We hereby surmised that Vitamin C concentration in blood might have been reduced by smoking.We concluded that it would be highly possible to use these vitamins in blood as biochemical markers which would indicate dietary intake during a short term(about 2 weeks) or a long term (about 1 year).