The mechanism for the difference between children and adults is unclear. It might be explained by the suggestion that children are more sensitive to LCn3PUFAs. Studies suggest that chronic inflammation may affect the immune system. It may be particularly true in children because a child’s immune system is under development. Presumably, LCn3PUFAs are important in the stage of immune system development. In other words, children may be more sensitive to LCn3PUFA intake than adults. Nevertheless, further studies are needed. Findings from other types of epidemiological studies on fish or LCn3PUFA and asthma are not so consistent. Two cross-sectional studies found an inverse association: one observed a 46% risk reduction in doctor-diagnosed asthma in children with per unit increment of fish consumption; and the other one reported that the risk of asthma reduced by 68% comparing those in the highest with those in the lowest tertile of fish consumption. However, another cross-sectional study found a positive association of fish consumption with the risk of asthma. In addition, one casecontrol study found a non-significant risk reduction comparing the highest fish consumption group with the lowest. Moreover, a meta-analysis summarized 9 _ENREF_33randomized controlled trials and found that LCn3PUFA supplementation was not associated with improved asthma symptoms, both in children and adults. Another meta-analysis on RCTs also reported a non-significant inverse association between fish oil supplementation and asthma risk in children. The null findings were in concordance with our results in adults. Of note, all included RCTs in that metaanalysis had relatively small sample sizes and short follow-up periods. Also, in RCTs, fish oil supplementation was used, which may reflect a different health impact from consuming whole fish �C a package of nutrients. Thus, our meta-analysis of cohort studies, coupled with the other meta-analysis of RCTs, provided important evidence for future research and primary prevention of asthma. Since our meta-analysis is based on observational studies, the inherent AbMole Metaproterenol Sulfate limitations of primary studies may have affected our findings. For example, the possibility of residual confounding cannot be ruled out. In addition, although we identified 11 cohort studies on this topic, these studies had to be divided into 3 subgroups because of the various 
exposure measurements. Nevertheless, our results should not be substantially biased given the potential biological mechanisms and the consistence with findings from RCTs. In conclusion, our pooled analysis suggests that intake of fish or LCn3PUFAs in AbMole BI-9564 expectant mothers or infants is inversely associated with asthma development, particularly, in childhood.