The average life span of Mongolians is 62 years for males and 69 years for females. This life span is about 16 years shorter than that of Japanese. Mongolian people generally eat meat, fat and diary products but less vegetables or fruit. Thus, we investigated the state of oxidative stress and dietary habits of Mongolians. The investigation was performed in Murun city in the northwest area of Mongolia. A total of 164 healthy subjects (24–66 y) were enrolled. As a marker of reactive oxygen species, the levels of reactive oxygen metabolites (ROM) were measured using the d-ROM test. Interviews about dietary habits were performed using the Food Frequency Questionnaire established by the Kagawa Nutrition University. ROM levels were 429.7 ± 95.2 Carr U for Murun subjects, whereas Japanese people (n = 220, 21–98 y) showed 335.3 ± 59.8 (p < 0.001). The levels of serum malondialdehyde-modified low-density lipoprotein-cholesterol and urinary 8-hydroxydeoxyguanosine were also high. ROM levels correlated with body fat ratio and inversely correlated with handgrip strength. Handgrip strength in the subjects over 45 years decreased more rapidly than that of age-matched Japanese. Murun subjects ate larger amounts of meat, fat, milk and flour and dairy products than Japanese, but less vegetables or fruit. Serum vitamin A and E levels were the same as Japanese references, but vitamin C levels were lower. Murun subjects may be in high oxidative stress, which may have a relationship with early ageing and several diseases, ultimately resulting in their short life span. In order to increase antioxidant capacity and suppress overproduction of ROM, antioxidant food intake is recommended.

We compared the relative validity of nutrient intakes derived from Internet website dish-based dietary records (WDDRs) and weighed dietary records (DRs). The study participants were 218 registered users of a dietary management website. After excluding 55 participants, a total of 163 participants were included in the final analyses. The participants were Japanese women, and their mean age and mean body mass index (BMI) were 39.3 (±10.3) years and 22.3 (±3.7) years, respectively. We compared differences in the DR and WDDR with respect to intakes of energy and 13 nutrients. The median values for the intake of protein and seven nutrients showed no significant difference between the DR and WDDR, and the estimated values were generally similar. The interquartile range of nutrients with a significant difference did not show a large deviation, with the exception of vitamin A. Correlation coefficients showed a strong correlation of 0.7, with the exception of sodium and vitamin E. The kappa coefficients for energy and for some nutrients were good to fair. Using Bland–Altman plots, we found proportional errors in the intake values for vitamins and minerals. We could not confirm obvious systematic errors for energy, protein, fat, or carbohydrate intake. WDDR use is considered to be a valid method for estimating energy and nutrient intakes among Japanese women.

We reported that the compositions of arachidonic acid (ARA) in erythrocytes and plasma phospholipids (PL) in the elderly were lower than those in the young, though the ARA intake was nearly identical. We further analyzed data in four study groups with different ages and sexes, and determined that the blood ARA levels were affected by the kinds of dietary fatty acids ingested. One hundred and four healthy young and elderly volunteers were recruited. Dietary records together with photographic records from 28 consecutive days were reviewed and the fatty acid composition in plasma lipid fractions and erythrocyte PL was analyzed. No correlations for ARA between dietary fatty acids and blood lipid fractions were observed. A significant negative correlation between eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) intake and ARA composition in erythrocyte PL was observed. ARA composition in erythrocyte PL was significantly lower in elderly subjects than in young subjects, because EPA and DHA intake in elderly subjects was higher than in young subjects. However, after removing the effect of dietary EPA+DHA intake, the ARA composition in erythrocyte PL in elderly subjects was significantly lower than that in young subjects. Changes in physical conditions with aging influenced the low ARA composition of erythrocyte in elderly subjects in addition to the effects of dietary EPA and DHA.

“Total” folate in blood has usually been measured to evaluate the folate status of pregnant women. However, folate is composed of many metabolites. The main substrate is 5-methyltetrahydrofolate (5-MTHF), with folic acid (FA) representing a very small component as an unmetabolized species in blood. We longitudinally evaluated 5-MTHF, FA and total homocysteine in maternal and cord blood from Japanese pregnant women. Subjects were 146 pregnant women who participated in the Chiba study of Mother and Child Health (C-MACH) prospective cohort study. Sera were obtained in early and late pregnancy, at delivery, and from cord blood. Species levels were measured by isotope-dilution mass spectrometry. Both 5-MTHF and FA levels were lower than reported levels from pregnant women in populations from countries with mandatory FA fortification. As gestational age progressed, serum 5-MTHF levels decreased, whereas serum FA levels were slightly reduced only at delivery compared to early pregnancy. A significant negative association between serum 5-MTHF and total homocysteine was shown at all examined times, but no associations with FA were evident. At delivery, cord 5-MTHF was significantly higher than maternal levels, while FA again showed no significant correlation. These results suggest that 5-MTHF is actively transported to the fetus through placental transporters and may reflect folate status during pregnancy as a physiologically important species.

Background: The transport of polyunsaturated fatty acids (PUFAs), such as arachidonic acid (ARA, 20:4n‐6) and docosahexaenoic acid (DHA, 22:6n‐3), to the fetus from maternal stores increases depending on the fetal requirements for PUFA during the last trimester of pregnancy. Therefore, maternal blood PUFA changes physiologically with gestational age. However, the changes in PUFA levels in maternal blood erythrocytes during pregnancy and after childbirth have not been fully investigated in a fish‐eating population. Objective: To examine the changes of ARA and DHA levels in maternal erythrocytes with the progress of pregnancy and the relationship between maternal and umbilical cord erythrocyte PUFA levels in pregnant Japanese women who habitually eat fish and shellfish. Design: This study was performed as a part of the adjunct study of the Japan Environment and Children’s Study (JECS). The participants were 74 pregnant women. The maternal blood samples were collected at 27, 30, and 36 weeks of pregnancy, and 2 days and 1 month after delivery, and umbilical cord blood was collected at delivery. The fatty acid levels of erythrocytes in these blood samples were determined. Results: ARA and DHA levels in maternal erythrocytes tended to decrease with the progress of pregnancy. While the DHA level decreased further after delivery, the ARA level returned to the value at 27 weeks of pregnancy within 1 month after delivery. The n‐3 and n‐6 PUFA levels in maternal erythrocytes at 27, 30, and 36 weeks of pregnancy were significantly positively correlated with the corresponding fatty acid levels in umbilical cord erythrocytes. Conclusion: The present findings showed a significant change in erythrocyte PUFA levels during pregnancy and after childbirth in a fish‐eating population. The PUFA levels of maternal blood after the second trimester may be a reliable marker for predicting PUFA levels in infants’ circulating blood.