• Breast milk fatty acid composition - 0, 2, 4 and 9 mo
  
• Fatty acid composition of infant RBC at 4 mo
  
• Visual acuity - 2 and 4 mo
  
• Follow-up:
  
• Anthropometric measures
  
• Blood pressure
  
• Ex vivo cytokine production (e.g. IL-10 and interferon-γ) in whole blood after 24 h of stimulation with bacterial components
  

• Anthropometric measures - 0, 2, 4 and 9 mo
  
• Problem solving at 9 mo
  
• Language development (CDI) at 1 and 2 y
  
• Contrast sensitivity at 2 mo
  
• Vernier acuity at 4 mo
  
• Follow-up:
  
• Heart rate variability
  
• Endothelial function measured by PWV
  
• Plasma IgE
  
• Diet
  
• RBC fatty acid composition
  
• Plasma growth factors
  

Background:

Studies indicate that infants, who are fed formula without n-3 LCPUFA, have slower visual development than those, who receive n-3 LCPUFA in breast-milk.

The mental development seems also to depend on whether infants are breast-fed or not. Long-term health has also been proposed to be affected (The infant origin of adult disease hypothesis). It is not clear whether these differences is due to dietary LCPUFA as comparison of breast-fed and formula-fed infants are complicated by the socio-demographic differences that exist between mother, who choose to breast-feed or not. Recent studies indicate that LCPUFA supplementation of formulas has beneficial effects on the visual acuity and mental abilities of infants. The LCPUFA content of breast-milk varies and this could potentially be of importance for infant development.

Methods:

211 pregnant women with a high (>80 percentile) or low (< mean) fish intake were recruited. After birth mother with low fish intake were randomized to receive 4 g/day of fish oil or olive oil for the first 4 months of the lactation period. 150 mother-infant pairs were followed for 1 year gathering information on maternal n-3 LCPUFA intake and infant development (growth, developmental milestones, visual acuity, cognitive functions and language acquisition). Milk samples were collected at 0, 2, 4 and 9 months and blood samples were taken from the mother and the infant at 4 months of age in order to determine the biochemical effect of the supplementation. The children were followed-up at 2½ years of age and around 7 years of age. The study is performed in association to the National Birth Cohort.