Association of allergies in children younger than 3 years with levels of maternal intake of n-3 polyunsaturated fatty acids or fish during pregnancy: A nationwide birth cohort study, the Japan Environment and Children's Study.

BACKGROUND: N-3 polyunsaturated fatty acids (PUFAs) have anti-inflammatory properties and are expected to prevent the onset of allergies. However, epidemiological studies investigating the relationship between child allergies and maternal intake of n-3 PUFAs or fish have yielded inconsistent results. METHODS: Following exclusions from a dataset comprising 103,057 records from the Japan Environment and Children's Study, 72,105 participants were divided into five groups according to mothers' intake of n-3 PUFAs or fish during pregnancy to assess the risk of their children being diagnosed with allergy by 3 years old. Adjusted odds ratios (aORs) with 95% confidence intervals (CIs) for child allergies were calculated using multivariable logistic regression analyses with reference to the lowest intake group. RESULTS: Levels of maternal intake of n-3 PUFAs or fish showed inverted associations (i.e., reduced risk) with the incidence of physician-diagnosed allergic rhinoconjunctivitis or parent-reported symptoms of current rhinitis with eye symptoms at different time points and the cumulative incidence from birth to 3 years of age. Inverted associations were also found for current wheeze at 1-<2 years of age and current eczema at 1-<2 and 0-<3 years of age. However, for food allergies, no significant associations were observed in the incidence in each group compared with the lowest intake group at any age. CONCLUSIONS: The findings suggest that n-3 PUFA intake during pregnancy may reduce the risk of developing allergic diseases and symptoms in children. In addition, consumption of n-3 PUFAs or fish is very unlikely to increase the risk of allergy given that the results are from a country with high fish consumption. TRIAL REGISTRATION: UMIN000030786 https://rctportal.niph.go.jp/detail/um?trial_id=UMIN000030786.

Association between Maternal Vitamin D Intake and Infant Allergies: The Japan Environment and Children's Study.

Maternal nutrition during pregnancy is one of the factors affecting the health of offspring. There are conflicting findings about the association between maternal vitamin D status and the development of allergic diseases in offspring. The purpose of this study is to evaluate the association between maternal vitamin D intake and the development of allergic diseases in offspring at 1 y of age. From an ongoing nationwide birth cohort study (the Japan Environment and Children's Study), we obtained information on maternal vitamin D intake, determined by a food frequency questionnaire, and parent-reported physician-diagnosed allergic diseases in offspring at 1 y of age. From the full dataset of 103,062 pregnancies, we analyzed complete data for 82,592 mother-offspring pairs. The prevalence of physician-diagnosed asthma, food allergy, and atopic dermatitis in the children was 2.5%, 6.6%, and 4.3%, respectively. The mean (± standard deviation) maternal vitamin D intake was 4.7±4.7 µg/d, which is much lower than the recommended amount in Japan (7 µg/d). After adjustment for various covariates, the odds ratios were significantly higher for asthma in the 2nd quintile and for food allergies in the 3rd and 4th quintiles compared with the 1st quintile. However, there were no clear associations between maternal vitamin D intake and the development of allergic diseases in offspring at 1 y of age, even in a large nation-wide cohort study. Protective effects of vitamin D supplementation remain unclear.

Dietary intake of fish and n-3 polyunsaturated fatty acids and risk of postpartum depression: a nationwide longitudinal study - the Japan Environment and Children's Study (JECS).

BACKGROUND: Pregnant women require increased levels of n-3 polyunsaturated fatty acids (PUFAs) due to the demands of the growing fetus. Although some evidence indicates that maternal intake of fish and n-3 PUFAs is associated with reduced risk of postpartum depression, the results are inconsistent. METHODS: We investigated whether dietary consumption of fish and/or n-3 PUFAs during pregnancy is associated with a reduced risk of maternal postpartum depression at 6 months after delivery and of serious mental illness at 1 year in a Japanese population. After exclusion and multiple imputation from a dataset comprising 103 062 pregnancies obtained in the Japan Environment and Children's Study, we evaluated 84 181 and 81 924 women at 6 months and 1 year after delivery, respectively. RESULTS: Multivariable logistic regression showed a reduced risk of postpartum depression at 6 months in the second to fifth quintiles v. the lowest quintile for fish and n-3 PUFA intake, with trend tests also revealing a significant linear association. At 1 year after delivery, fish intake was associated with a reduced risk of serious mental illness in the second to fifth quintiles v. the lowest quintile for fish and in the third to fifth quintiles v. the lowest quintile for n-3 PUFA intake, with trend tests also revealing a significant linear association. CONCLUSIONS: Women with higher fish and/or n-3 PUFA intake showed reduced risk of postpartum depression at 6 months after delivery and of serious mental illness at 1 year after delivery.

Dietary intake of fish and ω-3 polyunsaturated fatty acids and physician-diagnosed allergy in Japanese population: The Japan Environment and Children's Study.

OBJECTIVE: Emerging evidence from epidemiologic studies and clinical trials indicates that ω-3 polyunsaturated fatty acids (PUFAs) may have a preventive or therapeutic effect on allergy, although the results remain controversial. The aim of this study was to investigate the association between intake of fish and ω-3 PUFAs with risk for lifetime prevalence of physician-diagnosed allergy in a Japanese population. METHODS: Study participants were 78 621 pregnant women and 42 831 male partners from The Japan Environment and Children's Study. History of physician-diagnosed allergy (asthma, allergic rhinitis/pollinosis, allergic conjunctivitis, or atopic dermatitis) was determined by self-administered questionnaire survey. Dietary intake of fish and ω-3 PUFAs was estimated using a food frequency questionnaire. RESULTS: Contrary to our hypothesis, an increased risk for allergy was found by multivariable logistic regression in females, especially in allergic rhinitis/pollinosis, allergic conjunctivitis, or atopic dermatitis for fish intake and in allergic rhinitis/pollinosis or allergic conjunctivitis for ω-3 PUFAs. As for male partners, risk for allergic rhinitis/pollinosis or atopic dermatitis was increased for both fish and ω-3 PUFA intake. No statistically significant results were observed for the risk for asthma in either women or men. CONCLUSION: Fish and ω-3 PUFA intake were associated with increased risk for some allergic diseases. Further research is warranted to confirm these findings in individuals with high fish consumption.

Dietary intake of fish and n-3 polyunsaturated fatty acids and risks of perinatal depression: The Japan Environment and Children's Study (JECS).

The results of several epidemiological studies and clinical trials investigating the effects of n-3 polyunsaturated fatty acids (PUFAs) on antenatal and postnatal depression remain controversial. We investigated the possible association of dietary intake of fish and n-3 PUFAs with the risks of maternal and paternal psychological distress during pregnancy and of maternal postpartum depression in Japan. From a dataset comprising 104,102 maternal registrations and 52,426 paternal registrations in The Japan Environment and Children's Study, this study analyzed complete data on questionnaires for 75,139, 79,346, and 77,661 women during early pregnancy, mid-late pregnancy, and after pregnancy, respectively, and for 41,506 male partners. Multivariable logistic regression showed reduced risk of psychological distress in the second and third quintiles for fish intake in early pregnancy and in the second to fifth quintile in mid-late pregnancy. No reductions were observed for n-3 PUFA intake in early pregnancy but in the second to fourth quintile in mid-late pregnancy. For postpartum depression, reductions were observed in the second to fourth quintile for fish intake but only in the first quintile for n-3 PUFA intake. As for paternal psychological distress, only the fourth quintile for fish intake showed a significant reduced risk but none were shown for n-3 PUFA intake. In conclusion, fish intake was associated with some reduced risk of psychological distress during pregnancy, even for male partners. The associations were weaker for n-3 PUFA intake than for fish intake.