Dietary supplementation with n-3 polyunsaturated fatty acids in early childhood: effects on blood pressure and arterial structure and function at age 8 y.

BACKGROUND: n-3 Fatty acid supplementation in adults results in cardiovascular benefits. However, the cardiovascular effects of n-3 supplementation in early childhood are unknown. OBJECTIVE: The objective was to evaluate blood pressure (BP) and arterial structure and function in 8-y-old children who had participated in a randomized controlled trial of dietary n-3 and n-6 modification over the first 5 y of life. DESIGN: The children (n = 616; 49% girls) were randomly assigned antenatally to active (n = 312; increase in n-3 intake and decrease in n-6 intake) or control (n = 304) diet interventions implemented from the time of weaning or introduction of solids until 5 y of age. At age 8.0 +/- 0.1 y, BP, carotid intima-media thickness, carotid artery distensibility, augmentation index, and brachial pulse wave velocity were measured in 405 of these children. Venous blood was collected for measurement of plasma fatty acids, lipoproteins, high-sensitivity C-reactive protein, and asymmetric dimethylarginine. Plasma fatty acid concentrations were also assessed during the intervention. RESULTS: Plasma concentrations of n-3 fatty acids were higher and of n-6 were lower in the active than in the control diet group at 18 mo and 3 and 5 y (P < 0.0001). Concentrations of n-3 and n-6 fatty acids were similar at 8 y. At 8 y of age, no significant differences were found in BP, carotid intima-media thickness, carotid artery distensibility, augmentation index, asymmetric dimethylarginine, high-sensitivity C-reactive protein, or lipoproteins between diet groups. CONCLUSION: A dietary supplement intervention to increase n-3 and decrease n-6 intakes from infancy until 5 y does not result in significant improvements in arterial structure and function at age 8 y. This trial was registered at the Australian Clinical Trials Registry as ACTRN012605000042640.

Effect of omega 3 and omega 6 fatty acid intakes from diet and supplements on plasma fatty acid levels in the first 3 years of life.

BACKGROUND: The optimal method for conducting omega (n-)3 polyunsaturated fatty acid (PUFA) supplementation trials in children is unknown. AIM: To assess the impact of n-3 and n-6 PUFA intake from the background diet on plasma levels of n-3 and n-6 PUFA in children aged 0-3 years, with and without n-3 supplementation. METHODS: Subjects were randomised antenatally to receive either n-3 PUFA supplements and low n-6 PUFA cooking oils and spreads or a control intervention, designed to maintain usual fatty acid intake. Dietary intake was assessed at 18 months by 3-day weighed food record and at 3 years by food frequency questionnaire. Plasma phospholipids were measured at both time points. Associations were tested by regression. RESULTS: N-3 PUFA intake from background diet did not significantly affect plasma n-3 levels. In contrast, n-6 PUFA intake in background diet was positively related to plasma n-6 levels in both study groups. In addition, n-6 PUFA intake from diet was negatively associated with plasma n-3 levels at 18 months and 3 years (-0.16%/g n-6 intake, 95%CI -0.29 to -0.03 and -0.05%/g n-6 intake, 95%CI -0.09 to -0.01, respectively) in the active group, but not in the control group. CONCLUSION: Interventions intending to increase plasma n-3 PUFA in children by n-3 supplementation should also minimise n-6 PUFA intake in the background diet.

Omega-3 and omega-6 fatty acid exposure from early life does not affect atopy and asthma at age 5 years.

BACKGROUND: The Childhood Asthma Prevention Study was a randomized controlled trial conducted in children with a family history of asthma in whom omega-3 fatty acid supplementation and restriction of dietary omega-6 fatty acids did not prevent asthma, eczema, or atopy at age 5 years. OBJECTIVE: We sought to examine the relation of all measures of omega-3 and omega-6 polyunsaturated fatty acids with outcomes at age 5 years in the whole birth cohort, regardless of randomization group. METHODS: Plasma fatty acids were measured at 18 months, 3 years, and 5 years. Compliance with the fatty acid supplements was estimated every 6 months. Dietary intake was assessed at 18 months by means of weighed-food record and at 3 years by means of food-frequency questionnaire. At age 5 years, 516 children were examined for wheeze and eczema (questionnaire) and atopy (skin prick tests, n = 488). Multiple logistic regression was used to evaluate associations between exposures and outcomes. RESULTS: Plasma levels of omega-3 or omega-6 fatty acids were not associated with wheeze, eczema, or atopy at age 5 years (P = .11-.96). Overall, fatty acid exposure, measured as plasma levels, dietary intake, and compliance with supplements, was not associated with any respiratory or allergic outcomes (P = .35-.59). CONCLUSION: This observational analysis of the cohort, using the full range of observed variation in omega-3 and omega-6 fatty acid exposure, supports the negative findings of the randomized controlled trial. CLINICAL IMPLICATIONS: Modification of dietary polyunsaturated fatty acids in early childhood is not helpful in preventing atopy and asthma.

Prevention of asthma during the first 5 years of life: a randomized controlled trial.

BACKGROUND: Early life exposures may be important in the development of asthma and allergic disease. OBJECTIVE: To test house dust mite (HDM) avoidance and dietary fatty acid modification, implemented throughout the first 5 years of life, as interventions to prevent asthma and allergic disease. METHODS: We recruited newborns with a family history of asthma antenatally and randomized them, separately, to HDM avoidance or control and to dietary modification or control. At age 5 years, they were assessed for asthma and eczema and had skin prick tests for atopy. RESULTS: Of 616 children randomized, 516 (84%) were evaluated at age 5 years. The HDM avoidance intervention resulted in a 61% reduction in HDM allergen concentrations (microg/g dust) in the child's bed but no difference in the prevalence of asthma, wheeze, or atopy (P > .1). The prevalence of eczema was higher in the active HDM avoidance group (26% vs 19%; P = .06). The ratio of omega-6 to omega-3 fatty acids in plasma was lower in the active diet group (5.8 vs 7.4; P < .0001). However, the prevalence of asthma, wheezing, eczema, or atopy did not differ between the diet groups (P > .1). CONCLUSION: Further research is required to establish whether other interventions can be recommended for the prevention of asthma and allergic disease. CLINICAL IMPLICATIONS: House dust mite avoidance measures and dietary fatty acid modification, as implemented in this trial during infancy and early childhood, did not prevent the onset of asthma, eczema, or atopy in high-risk children.