DHA is important for the development of brain and retina in newborns. Considering that exclusive breast feeding for at least 4 ~6 months are globally recommended, plus it is well known that nutrient requirement is determined by both genetic and environmental (including diet) factors, this clinical study sought to investigate how the DHA levels in maternal milk is modulated by genetic variants and dietary n-3 LCPUFA intake. To recruit subjects (n=193), the inclusion criteria are Han Chinese women just having delivered full-term baby, 20-40 years old, healthy, and willing to breast feed their baby for at least 2 months. Written informed consent will be obtained from participants. Personal information (or covariates) such as height, weight (before getting pregnancy and delivery, respectively), age, parity, education, smoking, alcohol drinking, gender of baby…etc, and DNA from oral swab will be collected. Breast milk and dietary data will be collected at the end of the 1st and 2nd month of postpartum period. Considering Han Chinese women usually have special postpartum diets and care during puerperium, therefore, collection of breast milk and dietary information will be repeated at the 2nd month. The fatty acid composition in milk will be analyzed by gas chromatography. Using food frequency questionnaire, intake of n-3 LCPUFA from foods + fish oil supplements will be calculated. Subjects will be instructed to give a 3-days food record as well. We foresee results of this study might contribute to public health care as nutritionists/dietitians will be able to target the vulnerable subjects, who are dietary dependent for DHA, for dedications in nutrition consults or customized dietary guidance. Moreover, these information are valuable in making policy regarding dietary recommendation in Taiwan.

Inclusion Criteria:

• Han Chinese women
• Full-term pregnancy(>36weeks)
• 20-40 years old
• Healthy
• Breast feed their baby for at least 2 months

Exclusion Criteria:

• Death before and after childbirth
• Child with congenital disease

Of all 193 participants, there were 180 who continued to track for two months.