The role of long-chain polyunsaturated fatty acids in infant cognitive development

Possible role of tryptophan metabolism along the microbiota-gut-brain axis on cognitive & behavioral aspects in Phenylketonuria

Cognitive and psychiatric disorders are well documented across the lifetime of patients with inborn errors of metabolism (IEMs). Gut microbiota impacts behavior and cognitive functions through the gut-brain axis (GBA). According to recent research, a broad spectrum of GBA disorders may be influenced by a perturbed Tryptophan (Trp) metabolism and are associated with alterations in composition or function of the gut microbiota. Furthermore, early-life diets may influence children's neurodevelopment and cognitive deficits in adulthood. In Phenylketonuria (PKU), since the main therapeutic intervention is based on a life-long restrictive diet, important alterations of gut microbiota have been observed. Studies on PKU highlight the impact of alterations of gut microbiota on the central nervous system (CNS), also investigating the involvement of metabolic pathways, such as Trp and kynurenine (KYN) metabolisms, involved in numerous neurodegenerative disorders. An alteration of Trp metabolism with an imbalance of the KYN pathway towards the production of neurotoxic metabolites implicated in numerous neurodegenerative and inflammatory diseases has been observed in PKU patients supplemented with Phe-free amino acid medical foods (AA-MF). The present review investigates the possible link between gut microbiota and the brain in IEMs, focusing on Trp metabolism in PKU. Considering the evidence collected, cognitive and behavioral well-being should always be monitored in routine IEMs clinical management. Further studies are required to evaluate the possible impact of Trp metabolism, through gut microbiota, on cognitive and behavioral functions in IEMs, to identify innovative dietetic strategies and improve quality of life and mental health of these patients.

Effects of mono- and di-glycerides/phospholipids (MDG/PL) on the bioaccessibility of lipophilic nutrients in a protein-based emulsion system

Lipophilic nutrients are known to have relatively poor absorption, thus limiting their bioaccessibility. Consequently, researchers in food and pharmaceutical areas are exploring different techniques to promote the efficient delivery of lipophilic nutrients. The effects of two polar lipids, namely mono-, di-glycerides (MDG) and lecithin (PL), on the bioaccessibility of lipophilic nutrients were investigated in this study with a protein-based emulsion model system. During the emulsion preparation and formation, the incorporation of MDG/PL was found to benefit the dissolution and stabilization of lipophilic nutrients, such as lutein, and could also modify the construction of the emulsion surface. An in vitro digestion study showed that the use of MDG/PL could significantly increase the bioaccessibility of lipophilic nutrients [lutein, vitamin E, and docosahexaenoic acid (DHA)] by 13.52%, 186.90%, and 36.17% in a protein-based emulsion system. The use of MDG and PL decreased the interfacial tension in all the samples: protein only 20.65 mN m^-1, protein-PL 6.47 mN m^-1, and protein-MDG/PL 4.23 mN m^-1, as well as 12.11 mN m^-1, 1.26 mN m^-1 and 1.16 mN m^-1 with the presence of bile salts. Caco-2 cell culture results showed that, with the application of MDG/PL, the absorption rate of micelles was higher than that in the other groups and this resulted in a 70% absorption increase for lutein. Therefore, MDG/PL can improve the lipophilic nutrient absorption via promoting the affinity of formed micelles to the enterocytes of the small intestine. This study exhibited the effectiveness of MDG/PL on improving the bioaccessibility of lipophilic nutrients in a protein-based emulsion system mimicking the digestion and absorption fate of breast milk in an infant's gastric intestinal tract, thus suggesting that MDG/PL can be used as a technical pathway to improve the absorption of lipophilic nutrients.

Metabolomic and lipidomic characterization of an X-chromosome deletion disorder in neural progenitor cells by UHPLC-HRMS

INTRODUCTION

Intellectual disorders involving deletions of the X chromosome present a difficult task in the determination of a connection between symptoms and metabolites that could lead to treatment options. One specific disorder of X-chromosomal deletion, Fragile X syndrome, is the most frequently occurring of intellectual disabilities. Previous metabolomic studies have been limited to mouse models that may not have sufficiently revealed the full biochemical diversity of the disease in humans.

OBJECTIVES

The primary objective of this study was to elucidate the human biochemistry in X-chromosomal deletion disorders through metabolomic and lipidomic profiling, using cells from a X-deletion patient as a representative case.

METHODS

Metabolomic and lipidomic analysis was performed by UHPLC-HRMS on neural progenitor (NP) cells isolated from an afflicted female patient versus normal neural progenitor cells.

RESULTS

Results showed perturbations in several metabolic pathways, including those of arginine and proline, that significantly impact both neurotransmitter generation and overall brain function. Coincidently, dysregulation was observed for lipids involved in both cellular structure and membrane integrity. The trends of observed metabolomic changes, as well as lipidomic profiling from identified features, are discussed.

CONCLUSION

The lipidomic and metabolomic profiles of NP cell samples exhibited significant differentiation associated with partial deletion of the X chromosome. These findings suggest that rare X-chromosomal deletion disorders are not only a mental disorder limited to alterations in local neuronal functions, but are also metabolic diseases.

Impact of Arachidonic and Docosahexaenoic Acid Supplementation on Neural and Immune Development in the Young Pig

Background: Human milk contains both arachidonic acid (ARA) and docosahexaenoic acid (DHA). Supplementation of infant formula with ARA and DHA results in fatty acid (FA) profiles, neurodevelopmental outcomes, and immune responses in formula-fed infants that are more like those observed in breastfed infants. Consequently, ARA and DHA have been historically added together to infant formula. This study investigated the impact of ARA or DHA supplementation alone or in combination on tissue FA incorporation, immune responses, and neurodevelopment in the young pig.

Methods: Male pigs (N = 48 total) received one of four dietary treatments from postnatal day (PND) 2–30. Treatments targeted the following ARA/DHA levels (% of total FA): CON (0.00/0.00), ARA (0.80/0.00), DHA (0.00/0.80), and ARA+DHA (0.80/0.80). Plasma, red blood cells (RBC), and prefrontal cortex (PFC) were collected for FA analysis. Blood was collected for T cell immunophenotyping and to quantify a panel of immune outcomes. Myelin thickness in the corpus callosum was measured by transmission electron microscopy and pig movement was measured by actigraphy.

Results: There were no differences in formula intake or growth between dietary groups. DHA supplementation increased brain DHA, but decreased ARA, compared with all other groups. ARA supplementation increased brain ARA compared with all other groups but did not affect brain DHA. Combined supplementation increased brain DHA levels but did not affect brain ARA levels compared with the control. Pigs fed ARA or ARA+DHA exhibited more activity than those fed CON or DHA. Diet-dependent differences in activity suggested pigs fed ARA had the lowest percent time asleep, while those fed DHA had the highest. No differences were observed for immune or myelination outcomes.

Conclusion: Supplementation with ARA and DHA did not differentially affect immune responses, but ARA levels in RBC and PFC were reduced when DHA was provided without ARA. Supplementation of either ARA or DHA alone induced differences in time spent asleep, and ARA inclusion increased general activity. Therefore, the current data support the combined supplementation with both ARA and DHA in infant formula and raise questions regarding the safety and nutritional suitability of ARA or DHA supplementation individually.

A Meta-Analysis of Stressors from the Total Environment Associated with Children's General Cognitive Ability

General cognitive ability, often referred to as ‘general intelligence’, comprises a variety of correlated abilities. Childhood general cognitive ability is a well-studied area of research and can be used to predict social outcomes and perceived success. Early life stage (e.g., prenatal, postnatal, toddler) exposures to stressors (i.e., chemical and non-chemical stressors from the total (built, natural, social) environment) can impact the development of childhood cognitive ability. Building from our systematic scoping review (Ruiz et al., 2016), we conducted a meta-analysis to evaluate more than 100 stressors related to cognitive development. Our meta-analysis identified 23 stressors with a significant increase in their likelihood to influence childhood cognitive ability by 10% or more, and 80 stressors were observed to have a statistically significant effect on cognitive ability. Stressors most impactful to cognition during the prenatal period were related to maternal health and the mother’s ability to access information relevant to a healthy pregnancy (e.g., diet, lifestyle). Stressors most impactful to cognition during the early childhood period were dietary nutrients (infancy), quality of social interaction (toddler), and exposure to toxic substances (throughout early childhood). In conducting this analysis, we examined the relative impact of real-world exposures on cognitive development to attempt to understand the inter-relationships between exposures to both chemical and non-chemical stressors and early developmental life stages. Our findings suggest that the stressors observed to be the most influential to childhood cognitive ability are not permanent and can be broadly categorized as activities/behaviors which can be modified to improve childhood cognition. This meta-analysis supports the idea that there are complex relationships between a child’s total environment and early cognitive development.

The Kansas University DHA Outcomes Study (KUDOS) clinical trial: long-term behavioral follow-up of the effects of prenatal DHA supplementation

BACKGROUND

Docosahexaenoic acid (DHA) is a long-chain polyunsaturated fatty acid that has been linked to improved vision and cognition in postnatal feeding studies and has been consistently associated with reduction of early preterm birth in prenatal supplementation trials. This is a report of the first long-term follow-up of infants from mothers receiving prenatal DHA supplementation in a US cohort.

OBJECTIVE

Our objective was to evaluate the efficacy of the prenatal supplementation on both global and granular longitudinal assessments of cognitive and behavioral development.

METHODS

In a randomized double-blind clinical trial, mothers received either 600 mg/d of DHA or a placebo beginning at 14.5 weeks of gestation and capsules were provided until delivery. Children from those pregnancies were followed by cognitive and behavioral assessments administered from 10 mo through 6 y of age. From 301 mothers in the initial study, ∼200 infants completed the longitudinal schedule.

RESULTS

Although this intervention had been shown to reduce high-risk pregnancies and improve visual attention in infants during the first year, only a few positive long-term effects of prenatal DHA supplementation emerged from analyses of this follow-up. Increases in maternal blood DHA during pregnancy were related to verbal and full scale intelligence quotient (IQ) scores at 5 and 6 y, but these effects disappeared after controlling for SES. Maternal blood DHA concentrations at delivery were unrelated to outcomes, although maternal DHA at enrollment was related to productive vocabulary at 18 mo.

CONCLUSIONS

Although prenatal DHA supplementation substantially reduced early preterm birth and improved visual attention in infancy in this sample, no consistent long-term benefits were observed into childhood. Increases in maternal blood DHA concentration in pregnancy were related to higher IQs but this effect was confounded with SES and disappeared when SES was statistically controlled. This trial was registered at http://www.clinicaltrials.gov as NCT00266825 and NCT02487771.

Neither n-3 Long-Chain PUFA Supplementation of Mothers through Lactation nor of Offspring in a Complementary Food Affects Child Overall or Social-Emotional Development: A 2 × 2 Factorial Randomized Controlled Trial in Rural Ethiopia

BACKGROUND

The n-3 (ω-3) long-chain polyunsaturated fatty acid (LC-PUFA) docosahexaenoic acid (DHA) is essential for optimal brain development. There is a lack of evidence on the effect of postnatal n-3 LC-PUFA supplementation on child development in low-income countries.

OBJECTIVE

We evaluated the efficacy of fish-oil supplementation through lactation or complementary food supplementation on the development of children aged 6-24 mo in rural Ethiopia.

METHODS

We conducted a double-blind randomized controlled trial of n-3 LC-PUFA supplementation for 12 mo using fish-oil capsules [maternal intervention: 215 mg DHA + 285 mg eicosapentaenoic acid (EPA)] or a fish-oil-enriched complementary food supplement (child intervention: 169 mg DHA + 331 mg EPA). In total, 360 pairs of mothers and infants aged 6-12 mo were randomly assigned to 4 arms: maternal intervention and child control, child intervention and maternal control, maternal and child intervention, and maternal and child control. Primary outcomes were overall developmental performance with the use of a culturally adapted Denver II test that assesses personal-social, language, fine-motor, and gross-motor domains and social-emotional developmental performance using the Ages and Stages Questionnaire: Social Emotional at baseline and at 6 and 12 mo. We used mixed-effects models to estimate intervention effects on developmental performance over time (intervention × time interaction).

RESULTS

The evolution in overall and social-emotional developmental performance over time did not differ across study arms (intervention × time: F = 1.09, P = 0.35, and F = 0.61, P = 0.61, respectively). Effects did not change after adjustment for child age, birth order, and nutritional status; maternal age and education; wealth; family size; and breastfeeding frequency. Children's developmental performance significantly decreased during study follow-up (β: -0.03 SDs/mo; 95% CI: -0.04, -0.01 SD/mo; P < 0.01).

CONCLUSIONS

n-3 LC-PUFA supplementation does not affect overall or social-emotional development of children aged 6-24 mo in a low-income setting. Follow-up of the cohort is recommended to determine whether there are long-term effects of the intervention. This trial was registered at clinicaltrials.gov as NCT01817634.

Maternal DHA Status during Pregnancy Has a Positive Impact on Infant Problem Solving: A Norwegian Prospective Observation Study

Docosahexaenoic acid (DHA, 22:6, n-3) is a long-chain polyunsaturated fatty acid necessary for normal brain growth and cognitive development. Seafood and dietary supplements are the primary dietary sources of DHA. This study addresses the associations between DHA status in pregnant women and healthy, term-born infant problem-solving skills assessed using the Ages and Stages Questionnaire. The fatty acid status of maternal red blood cells (RBCs) was assessed in the 28th week of gestation and at three months postpartum. The infants’ fatty acid status (RBC) was assessed at three, six, and twelve months, and problem-solving skills were assessed at six and twelve months. Maternal DHA status in pregnancy was found to be positively associated with infants’ problem-solving skills at 12 months. This association remained significant even after controlling for the level of maternal education, a surrogate for socio-economic status. The infants’ DHA status at three months was associated with the infants’ problem solving at 12 months. The results accentuate the importance for pregnant and lactating women to have a satisfactory DHA status from dietary intake of seafood or other sources rich in DHA.

Synergistic Effects of Human Milk Nutrients in the Support of Infant Recognition Memory: An Observational Study

The aim was to explore the relation of human milk lutein; choline; and docosahexaenoic acid (DHA) with recognition memory abilities of six-month-olds. Milk samples obtained three to four months postpartum were analyzed for fatty acids, lutein, and choline. At six months, participants were invited to an electrophysiology session. Recognition memory was tested with a 70-30 oddball paradigm in a high-density 128-lead event-related potential (ERP) paradigm. Complete data were available for 55 participants. Data were averaged at six groupings (Frontal Right; Frontal Central; Frontal Left; Central; Midline; and Parietal) for latency to peak, peak amplitude, and mean amplitude. Difference scores were calculated as familiar minus novel. Final regression models revealed the lutein X free choline interaction was significant for the difference in latency scores at frontal and central areas (p < 0.05 and p < 0.001; respectively). Higher choline levels with higher lutein levels were related to better recognition memory. The DHA X free choline interaction was also significant for the difference in latency scores at frontal, central, and midline areas (p < 0.01; p < 0.001; p < 0.05 respectively). Higher choline with higher DHA was related to better recognition memory. Interactions between human milk nutrients appear important in predicting infant cognition, and there may be a benefit to specific nutrient combinations.

Comparison of the nutrient composition of commercial dog milk replacers with that of dog milk

OBJECTIVE

To compare the nutrient composition of commercially available dog milk replacers with that of dog milk.

DESIGN

Prospective, cross-sectional study.

SAMPLE

5 dog milk samples and 15 samples of commercial dog milk replacers.

PROCEDURES

Dog milk and milk replacers were analyzed for concentrations of total protein, essential amino acids, sugars, total fat, essential fatty acids, calcium, and phosphorus. Energy density was calculated. Results from milk replacers were compared with the range of the concentration of each nutrient in milk samples from mature dogs as well as the National Research Council (NRC) recommendations for puppy growth.

RESULTS

Milk replacers varied widely in caloric density and concentration of nutrients such as calcium, protein, and fat. Calcium concentration was lower in 14 of 15 milk replacers than in the dog milk samples. Docosahexaenoic acid was undetectable in 12 of 15 milk replacers but present in all dog milk samples. All milk replacers had numerous essential nutrients outside of the range of the dog milk samples, and many had concentrations of amino acids, essential fatty acids, calcium, and phosphorus less than the NRC minimal requirement or recommended allowance. Compared with NRC recommendations, some dog milk samples had concentrations of total protein, linoleic acid, calcium, or phosphorus less than the recommended allowance.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested that there was substantial variation in nutrient composition of 15 dog milk replacers and that some products were closer approximations of dog milk than others. Nearly all products would benefit from more appropriate calcium, amino acids, and essential fatty acids concentrations and better feeding directions.

Maternal micronutrient imbalance alters gene expression of BDNF, NGF, TrkB and CREB in the offspring brain at an adult age

Micronutrients like folate, vitamin B12, and fatty acids which are interlinked in the one carbon cycle play a vital role in mediating epigenetic processes leading to an increased risk for neurodevelopmental disorders in the offspring. Our earlier study demonstrates that a micronutrient imbalanced diet adversely affects docosahexaenoic acid (DHA) and protein levels of neurotrophins like brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in the brain and cognition in the offspring by 3 months of age. In this study we attempt to analyze if these effects are a consequence of a change in gene expression of these molecules. Further, we also examined the effect of either a postnatal control diet or a prenatal omega-3 fatty acid supplementation on gene expression in the cortex of the offspring. Pregnant rats were divided into control and five treatment groups at two levels of folic acid (normal and excess folate) in the presence and absence of vitamin B12. Omega-3 fatty acid (eicosapentaenoic acid - EPA+DHA) supplementation was given to vitamin B12 deficient groups. Following delivery, 8 dams from each group were shifted to control diet and remaining continued on the same treatment diet. Our results demonstrate that the imbalanced diet caused a marked reduction in the mRNA levels of BDNF, NGF, TrkB, and cAMP response element-binding protein (CREB). Prenatal omega-3 fatty acid supplementation to the maternal imbalanced diet was able to normalize the mRNA levels of all the above genes. This study demonstrates that a maternal diet imbalanced in micronutrients (folic acid, vitamin B12) influences gene expression of neurotrophins and their signalling molecules and thereby adversely affects the brain of the offspring.

2'-fucosyllactose: an abundant, genetically determined soluble glycan present in human milk

Lactose is the preeminent soluble glycan in milk and a significant source of energy for most newborn mammals. Elongation of lactose with additional monosaccharides gives rise to a varied repertoire of free soluble glycans such as 2'-fucosyllactose (2'-FL), which is the most abundant oligosaccharide in human milk. In infants, 2'-FL is resistant to digestion and reaches the colon where it is partially fermented, behaving as soluble prebiotic fiber. Evidence also suggests that portions of small soluble milk glycans, including 2'-FL, are absorbed, thus raising the possibility of systemic biological effects. 2'-FL bears an epitope of the Secretor histo-blood group system; approximately 70-80% of all milk samples contain 2'-FL, since its synthesis depends on a fucosyltransferase that is not uniformly expressed. The fact that some infants are not exposed to 2'-FL has helped researchers to retrospectively probe for biological activities of this glycan. This review summarizes the attributes of 2'-FL in terms of its occurrence in mammalian phylogeny, its postulated biological activities, and its variability in human milk.

Long-term effects of LCPUFA supplementation on childhood cognitive outcomes

BACKGROUND

The effect of long-chain polyunsaturated fatty acid (LCPUFA) intake on cognitive development is controversial. Most randomized trials have assessed cognition at 18 mo, although significant development of cognitive abilities (early executive function) emerge later.

OBJECTIVE

The objective was to evaluate cognition beyond 18 mo and longitudinal cognitive change from 18 mo to 6 y in children who were fed variable amounts of docosahexaenoic acid (0.32%, 0.64%, and 0.96% of total fatty acids) and arachidonic acid (ARA; 0.64%) compared with children who were not fed LCPUFA as infants.

DESIGN

Eighty-one children (19 placebo, 62 LCPUFA) who participated in a double-blind, randomized trial of LCPUFA supplementation as infants were re-enrolled at 18 mo and tested every 6 mo until 6 y on age-appropriate standardized and specific cognitive tests.

RESULTS

LCPUFA supplementation did not influence performance on standardized tests of language and performance at 18 mo; however, significant positive effects were observed from 3 to 5 y on rule-learning and inhibition tasks, the Peabody Picture Vocabulary Test at 5 y, and the Weschler Primary Preschool Scales of Intelligence at 6 y. Effects of LCPUFAs were not found on tasks of spatial memory, simple inhibition, or advanced problem solving.

CONCLUSIONS

The data from this relatively small trial suggest that, although the effects of LCPUFAs may not always be evident on standardized developmental tasks at 18 mo, significant effects may emerge later on more specific or fine-grained tasks. The results imply that studies of nutrition and cognitive development should be powered to continue through early childhood. This parent trial was registered at clinicaltrials.gov as NCT00266825.

Nutrition and neurodevelopment in children: focus on NUTRIMENTHE project

There is growing evidence that early nutrition affects later cognitive performance. The idea that the diet of mothers, infants, and children could affect later mental performance has major implications for public health practice and policy development and for our understanding of human biology as well as for food product development, economic progress, and future wealth creation. To date, however, much of the evidence is from animal, retrospective studies and short-term nutritional intervention studies in humans. The positive effect of micronutrients on health, especially of pregnant women eating well to maximise their child's cognitive and behavioural outcomes, is commonly acknowledged. The current evidence of an association between gestational nutrition and brain development in healthy children is more credible for folate, n-3 fatty acids, and iron. Recent findings highlight the fact that single-nutrient supplementation is less adequate than supplementation with more complex formulae. However, the optimal content of micronutrient supplementation and whether there is a long-term impact on child's neurodevelopment needs to be investigated further. Moreover, it is also evident that future studies should take into account genetic heterogeneity when evaluating nutritional effects and also nutritional recommendations. The objective of the present review is to provide a background and update on the current knowledge linking nutrition to cognition and behaviour in children, and to show how the large collaborative European Project NUTRIMENTHE is working towards this aim.

The pilot study: sphingomyelin-fortified milk has a positive association with the neurobehavioural development of very low birth weight infants during infancy, randomized control trial

AIM

This study was a randomised control trial to examine the effects of sphingomyelin (SM), on the mental, motor and behavioural development of premature infants.

PATIENTS AND METHODS

Randomised, double-blind controlled trial, enroling infants born with a birth weight of less than 1500 g between January 2004 and October 2007 at Juntendo University Hospital, with follow-up to 18 months. Twenty-four preterm babies were randomly assigned; 12 were assigned to a test group and fed SM-fortified milk (SM 20% of all phospholipids in milk) and 12 were assigned to a control group (SM 13% of all phospholipids in milk). We analysed the composition of the plasma phospholipids and red-cell-membrane fatty acids, after which VEP, Fagan, BSID-II, attention and memory tests were performed.

RESULTS

The percentage of SM in the total phospholipids was significantly higher in the trial group than in the control group at 4, 6 and 8 weeks. The Behaviour Rating Scale of the BSID-II, the Fagan test scores, the latency of VEP, and sustained attention test scores at 18 months were all significantly better in the trial group than in the control group.

CONCLUSION

This study is the first to report that nutritional intervention via administration of SM-fortified milk has a positive association with the neurobehavioural development of low-birth-weight infants. However, detailed studies on the effects of SM on longer-term development are required.

A double-blind, placebo-controlled trial of ω-3 fatty acids in Tourette's disorder

OBJECTIVE

Clinical observations have suggested therapeutic effects for ω-3 fatty acids (O3FA) in Tourette's disorder (TD), but no randomized, controlled trials have been reported. In a placebo-controlled trial, we examined the efficacy of O3FA in children and adolescents with TD.

METHODS

Thirty-three children and adolescents (ages 6-18) with TD were randomly assigned, double-blind, to O3FA or placebo for 20 weeks. O3FA consisted of combined eicosapentaenoic acid and docosahexaenoic acid. Placebo was olive oil. Groups were compared by using (1) intent-to-treat design, with the last-observation-carried-forward controlling for baseline measures and attention-deficit/hyperactivity disorder via (a) logistic regression, comparing percentage of responders on the primary Yale Global Tic Severity Scale (YGTSS)-Tic and secondary (YGTSS-Global and YGTSS-Impairment) outcome measures and (b) analysis of covariance; and (2) longitudinal mixed-effects models.

RESULTS

At end point, subjects treated with O3FA did not have significantly higher response rates or lower mean scores on the YGTSS-Tic (53% vs 38%; 15.6 ± 1.6 vs 17.1 ± 1.6, P > .1). However, significantly more subjects on O3FA were considered responders on the YGTSS-Global measure (53% vs 31%, P = .05) and YGTSS-Impairment measure (59% vs 25%, P < .05), and mean YGTSS-Global scores were significantly lower in the O3FA-treated group than in the placebo group (31.7 ± 2.9 vs 40.9 ± 3.0, P = .04). Obsessive-compulsive, anxiety, and depressive symptoms were not significantly affected by O3FA. Longitudinal analysis did not yield group differences on any of the measures.

CONCLUSIONS

O3FA did not reduce tic scores, but it may be beneficial in reduction of tic-related impairment for some children and adolescents with TD. Limitations include the small sample and the possible therapeutic effects of olive oil.

Long-chain polyunsaturated fatty acid supplementation in infancy reduces heart rate and positively affects distribution of attention

A double-blind, randomized, controlled, parallel-group prospective trial was conducted to determine whether a dose-response existed for four different levels of docosahexaenoic acid (DHA) supplementation on the cognitive performance of infants. A total of 122 term infants were fed one of four different formulas varying in their DHA composition (0.00, 0.32, 0.64, and 0.96% of total fatty acids as DHA) from birth to 12 mo. The three DHA-supplemented formulas also contained 0.64% of total fatty acids as arachidonic acid (ARA, 20:4n-6). Infants were tested at 4, 6, and 9 mo of age on a visual habituation protocol that yielded both behavioral and psychophysiological indices of attention. Infants in all DHA+ARA-supplemented conditions had lower heart rates than those in the unsupplemented condition; there was no dose-response for this effect. The distribution of time that infants spent in different phases of attention (a cognitive index derived from the convergence of behavioral and cardiac responses) varied as a function of dosage. Infants supplemented at the two lower DHA doses spent proportionately more time engaged in active stimulus processing than infants fed the unsupplemented formula, whereas infants fed the highest dose were intermediate and did not differ from any other group.

STUDY ON BIOLOGICAL CHARACTERISTICS OF HETEROTROPHIC MARINE MICROALGA-SCHIZOCHYTRIUM MANGROVEI PQ6 ISOLATED FROM PHU QUOC ISLAND, KIEN GIANG PROVINCE, VIETNAM(1)

Schizochytrium sp. PQ6, a heterotrophic microalga isolated from Phu Quoc (PQ) Island in the Kien Giang province of Vietnam, contains a high amount of docosahexaenoic acid (DHA, C22:6n-3). In this study, the culture conditions are developed to maximize biomass and DHA production. Nucleotide sequence analysis of partial 18S rRNA gene from genomic DNA showed that PQ6 has a phylogenetic relationship close to Schizochytrium mangrovei Raghu-Kumar. The highest growth rate and DHA accumulation of this strain were obtained in 6.0% glucose, 1.0% yeast extract, 50% artificial seawater (ASW), and pH 7 at 28°C. In addition, carbon and nitrogen sources could be replaced by glycerol, ammonium acetate, sodium nitrate, or fertilizer N-P-K. Total lipid content reached 38.67% of dry cell weight (DCW), in which DHA and eicosapentaenoic acid (EPA, C20:5n-3) contents accounted for 43.58% and 0.75% of the total fatty acid (TFA), respectively. In 5 and 10 L fermenters, the cell density, DCW, total lipid content, and maximum DHA yield were 46.50 × 10(6)  cells · mL(-1) , 23.7 g · L(-1) , 38.56% of DCW, and 8.71 g · L(-1) (in 5 L fermenter), respectively, and 49.71 × 10(6)  cells · mL(-1) , 25.34 g · L(-1) , 46.23% of DCW, and 11.55 g · L(-1) (in 10 L fermenter), respectively. Biomass of PQ6 strain possessed high contents of Na, I, and Fe (167.185, 278.3, and 43.69 mg · kg(-1) DCW, respectively). These results serve as a foundation for the efficient production of PQ6 biomass that can be used as a food supplement for humans and aquaculture in the future.

Achieving definitive results in long-chain polyunsaturated fatty acid supplementation trials of term infants: factors for consideration

Numerous randomized controlled trials (RCTs) have been undertaken to determine whether supplementation with long-chain polyunsaturated fatty acids (LCPUFAs) in infancy would improve the developmental outcomes of term infants. The results of such trials have been thoroughly reviewed with no definitive conclusion as to the efficacy of LCPUFA supplementation. A number of reasons for the lack of conclusive findings in this area have been proposed. This review examines such factors with the aim of determining whether an optimal method of investigation for RCTs of LCPUFA supplementation in term infants can be ascertained from previous research. While more research is required to completely inform a method that is likely to achieve definitive results, the findings of this literature review indicate future trials should investigate the effects of sex, genetic polymorphisms, the specific effects of LCPUFAs, and the optimal tests for neurodevelopmental assessment. The current literature indicates a docosahexaenoic acid dose of 0.32%, supplementation from birth to 12 months, and a total sample size of at least 286 (143 per group) should be included in the methodology of future trials.

Genetic variations of FACL4 have no obvious influence on cognitive ability in young Chinese children

The influence of genetic variants of FACL4 on individual cognitive ability was examined in a random sample of 213 boys and 224 girls. Both conventional genetic methods and analysis of variance were applied in this study. We found no significant relationship between FACL4 and cognitive function.

Effects of iron supplementation in nonanemic pregnant women, infants, and young children on the mental performance and psychomotor development of children: a systematic review of randomized controlled trials

BACKGROUND

Uncertainty exists regarding the effects of iron supplementation on neurodevelopmental outcomes in the absence of anemia.

OBJECTIVE

Our objective was to evaluate the effects of iron supplementation in nonanemic pregnant women and in nonanemic healthy children aged <3 y on the mental performance and psychomotor development of children.

DESIGN

In this systematic review, MEDLINE, EMBASE, and The Cochrane Library were searched through December 2009 for randomized controlled trials (RCTs).

RESULTS

None of 5 RCTs individually showed a beneficial effect of iron supplementation during early life on the Mental Developmental Index of the Bayley Scales of Infant Development at different ages throughout the first 18 mo. Meta-analysis of 3 RCTs (n = 561) showed that, compared with placebo, supplementation with iron had no significant effect on children's Mental Developmental Index at approximately 12 mo of age (weighted mean difference: 1.66; 95% CI: -0.14, 3.47). Three of 5 RCTs showed a beneficial effect of iron supplementation on the Psychomotor Development Index at some time points, whereas 2 did not. Meta-analysis of 3 RCTs (n = 561) showed significant improvement on the Psychomotor Development Index at approximately 12 mo of age in the iron-supplemented group compared with the control group (weighted mean difference: 4.21; 95% CI: 2.31, 6.12). Two RCTs showed no effect of iron supplementation on behavior. Neither of the 2 RCTs that addressed the influence of prenatal iron supplementation showed an effect of iron on either the intelligence quotient or behavioral status of the children.

CONCLUSION

Limited available evidence suggests that iron supplementation in infants may positively influence children's psychomotor development, whereas it does not seem to alter their mental development or behavior.

Influence of fish oil or folate supplementation on the time course of plasma redox markers during pregnancy

Maternal supplementation with long-chain PUFA, to improve infant neurological development, might cause additional increase of oxidative stress. Pregnant women aged 18-41 years were randomised into one of four supplementation groups. From week 22 on, they received supplements containing either modified fish oil (n 69), 5-methyl-tetrahydro-folate (n 65), both (n 64), or placebo (n 72). Plasma Trolox-equivalent antioxidative capacity (TEAC), concentrations of alpha-tocopherol, retinol, beta-carotene, free thiol groups, uric acid and thiobarbituric acid-reactive substances (TBARS) were determined at weeks 20 and 30 and at delivery. The studied antioxidants showed no significant differences between the four supplementation groups. At week 30 plasma TBARS levels were found to be significantly higher in the fish oil group (0.80 (sem 0.04) micromol/l) than in the folate (0.67 (sem 0.03) micromol/l; P = 0.024) and control (0.69 (sem 0.04) micromol/l; P = 0.01) groups. Concentrations of retinol and free thiol groups decreased during pregnancy, whereas uric acid increased and beta-carotene as well as TEAC showed only minor changes. Fish oil supplementation during the second half of pregnancy appears not to decrease antioxidant status. The increased TBARS levels at week 30 may indicate a period of increased oxidative stress in plasma at this time.

Preventing diet induced disease: bioavailable nutrient-rich, low-energy-dense diets

What the World needs is an integrated and sustainable food policy that makes the best and most appropriate use of the technologies at our disposal to promote health and help prevent disease. Diet induced diseases account for the largest burden of chronic illnesses and health problems Worldwide. Historically a lack of knowledge about human nutritional requirements (including for the brain) helped promote diet induced disease. The scientific knowledge currently exists to help prevent many of the current deficiencies and imbalances in human diet. Primary prevention of cardiovascular disease and mental ill health starts, crucially, with maternal nutrition before the inception of pregnancy and continues throughout life of the new born and includes consuming more DHA and EPA omega-3 fats (and their cofactors) and other bioavailable brain nutrients and less high-energy-dense (>2 kcal g(-1)) foods (e.g. land-based cereal, chocolate, alcohol and refined sugar, fat and oil), so tissues synthesize less inflammatory mediators and to lower transient short-lived meal-induced oxidative stress, inflammation, proliferation and impaired nitric oxide (e.g. approximately 0.35-3.5 g DHA/ EPA day(-1) dependant on energy intake and noting the importance of cofactors). Micro- and nanotechnologies are already engineering nano foods for human (and livestock) consumption that may eventually (without excessive consumption) prevent the current diet induced disease epidemic, especially in future generations, by preventing the causal mechanisms of disease. Greater knowledge about the causal mechanisms of disease awaits to be discovered, which could further enhance the human desire to increase longevity in optimum health (creating more problems and challenges for society).

Can early intake of dietary omega-3 predict childhood externalizing behaviour?

AIM

To determine whether maternal and child intake of dietary omega-3 (n-3) fatty acids (FA), together with the presence or absence of breast-feeding, predicted psychiatric diagnosis of externalizing disorders in childhood.

METHODS

Data concerning childhood externalizing disorders were collected from 8242 children aged 7.9 years in a large British cohort. Intake of n-3 FA was measured for the study mother during pregnancy and for the child at 3 years. Duration of breast-feeding was examined to account for moderating effects. Adjustment was made for a variety of potential confounders.

RESULTS

Maternal intake of n-3 and breast-feeding predicted oppositional/conduct disorder and comorbid externalizing disorder before adjustment for confounding factors. However, there was no association between intake of n-3 by mother or child and any type of externalizing disorder once socio-demographic factors were taken into account.

CONCLUSIONS

Any association between intake of n-3 and childhood externalizing disorders appears to be strongly confounded with socio-demographic factors. This is important to note given the current popularity of n-3 as a possible treatment for behaviour problems related to inattention and impulsivity. Care must be taken that studies investigating this relationship account fully for factors associated with both behaviour and diet.

Does breastfeeding in the neonatal period influence the cognitive function of very-low-birth-weight infants at 5 years of age?

AIM

Breast milk is rich in docosahexaenoic acid (DHA), which is selectively concentrated in neuronal membranes and is thought to be necessary for optimal neurodevelopment. This study evaluated the relationship between breastfeeding, especially the resultant DHA level in the red blood cell (RBC) membranes of infants, and the cognitive function of very-low-birth-weight infants at 5 years of age.

METHODS

Eighteen patients were classified into groups that were breastfed or formula-fed or both. We measured the DHA concentration in the RBC membranes of 18 preterm infants at 4 weeks of age. To evaluate cognitive function at the age of 5 years, we asked the children to perform five tests: the Kaufman Assessment Battery for Children, Day-Night Test, Kansas Reflection Impulsivity Scale for Preschoolers (KRISP), Motor Planning Test, and Strengths and Difficulties Questionnaire.

RESULTS

The DHA level at 4 weeks after birth was significantly higher in the breastfed infants than in the formula-fed infants. The scores for the Day-Night Test, KRISP, and Motor Planning Test were significantly higher in the breastfed group. There were significant correlations between the scores for the Day-Night Test and for the KRISP and the level of DHA at 4 weeks of age.

CONCLUSION

Breastfeeding in the neonatal periods increases the DHA level in preterm infants and may have an important influence on brain development not only during early infancy but also during the preschool years, especially in terms of cognitive function.

A randomised control trial in schoolchildren showed improvement in cognitive function after consuming a bread spread, containing fish flour from a marine source

BACKGROUND

In humans, n-3 long-chain polyunsaturated fatty acids play a well-documented role in brain development and function. Docosahexaenoic acid and arachidonic acid are major structural components of the brain and a deficiency thereof may bring about changes in the behaviour domains of the brain.

OBJECTIVE

This trial investigated the effect of an experimental fish-flour bread spread rich in n-3 long-chain polyunsaturated fatty acids, on cognition of children (7-9yr).

DESIGN

Subjects (n=183) were randomly assigned to an experimental (n=91) and control group (n=92), receiving either the fish-flour spread or a placebo spread for 6 months in a single-blind study. Plasma and red blood cell phospholipid fatty acid composition and cognition were measured at baseline and post-intervention.

RESULTS

After the intervention, eicosapentaenoic and docosahexaenoic acid levels were significantly higher in the experimental group compared to the control group (p< 0.0001). Significant intervention effects were also observed for the Hopkins Verbal Learning Test Recognition (estimated effect size: 0.80; 95% confidence interval (CI): 0.15; 1.45) and Discrimination Index (estimated effect size: 1.10; 95% CI: 0.30; 1.91), as well as the Spelling test (estimated effect size: 2.81; 95% CI: 0.59; 5.02) by both per protocol and intention to treat analyses. A marginally significant (p=0.0646) effect was observed for the Reading test (estimated effect size: 2.21; 95% CI: -0.14; 4.56) only in the per protocol analysis.

CONCLUSION

This study suggests improvement of verbal learning ability and memory of children when supplemented with a fish-flour spread rich in n-3 long-chain polyunsaturated fatty acids.

Docosahexaenoic acid and cognitive function: Is the link mediated by the autonomic nervous system?

Docosahexaenoic acid is a long-chain polyunsaturated fatty acid that is found in large quantity in the brain and which has repeatedly been observed to be related in positive ways to both cognitive function and cardiovascular health. The mechanisms through which docosahexaenoic acid affects cognition are not well understood, but in this article, we propose a hypothesis that integrates the positive effects of docosahexaenoic acid in the cognitive and cardiovascular realms through the autonomic nervous system. The autonomic nervous system is known to regulate vital functions such as heart rate and respiration, and has also been linked to basic cognitive components related to arousal and attention. We review the literature from this perspective, and delineate the predictions generated by the hypothesis. In addition, we provide new data showing a link between docosahexaenoic acid and fetal heart rate that is consistent with the hypothesis.

Improved cognitive development among preterm infants attributable to early supplementation of human milk with docosahexaenoic acid and arachidonic acid

OBJECTIVE

The objective of our study was to evaluate the effect of supplementation with docosahexaenoic acid and arachidonic acid for human milk-fed preterm infants. The primary end point was cognitive development at 6 months of age.

METHODS

The study was a randomized, double-blind, placebo-controlled study among 141 infants with birth weights of <1500 g. The intervention with 32 mg of docosahexaenoic acid and 31 mg of arachidonic acid per 100 mL of human milk started 1 week after birth and lasted until discharge from the hospital (on average, 9 weeks). Cognitive development was evaluated at 6 months of age by using the Ages and Stages Questionnaire and event-related potentials, a measure of brain correlates related to recognition memory.

RESULTS

There was no difference in adverse events or growth between the 2 groups. At the 6-month follow-up evaluation, the intervention group performed better on the problem-solving subscore, compared with the control group (53.4 vs 49.5 points). There was also a nonsignificant higher total score (221 vs 215 points). The event-related potential data revealed that infants in the intervention group had significantly lower responses after the standard image, compared with the control group (8.6 vs 13.2). There was no difference in responses to novel images.

CONCLUSIONS

Supplementation with docosahexaenoic acid and arachidonic acid for very preterm infants fed human milk in the early neonatal period was associated with better recognition memory and higher problem-solving scores at 6 months.

Systematic review of fatty acid composition of human milk from mothers of preterm compared to full-term infants

BACKGROUND

Fatty acid composition of human milk serves as guidance for the composition of infant formulae. The aim of the study was to systematically review data on the fatty acid composition of human milk of mothers of preterm compared to full-term infants.

METHODS

An electronic literature search was performed in English (Medline and Medscape) and German (SpringerLink) databases and via the Google utility. Fatty acid compositional data for preterm and full-term human milk were converted to differences between means and 95% confidence intervals.

RESULTS

We identified five relevant studies publishing direct comparison of fatty acid composition of preterm versus full-term human milk. There were no significant differences between the values of the principal saturated and monounsaturated fatty acids. In three independent studies covering three different time points of lactation, however, docosahexaenoic acid (DHA) values were significantly higher in milk of mothers of preterm as compared to those of full-term infants, with an extent of difference considered nutritionally relevant.

CONCLUSION

Higher DHA values in preterm than in full-term human milk underlines the importance of using own mother's milk for feeding preterm babies and raises the question whether DHA contents in preterm formulae should be higher than in formulae for full-term infants.

Engineering oilseeds to produce nutritional fatty acids

There is a growing body of evidence suggesting that regular consumption of foods rich in omega-3 long chain polyunsaturated fatty acids has multiple positive health benefits. The fats and oils from marine fish contain high contents of these beneficial fatty acids but increased consumer demand has also increased strain on the ability of the world's fisheries to meet demand from wild capture. Many consumers are choosing fish oil supplements or are eating foods that have been complemented with fish oils instead of consuming fish directly. However, removing undesirable odors, flavors and contaminants is expensive. In contrast, oils derived from land plants such as soybean are inexpensive and contaminant free. Recent strides in plant molecular biology now allow the engineering of oilseeds for the production of novel fats and oils, including those synthesized by complex, multigene biosynthetic pathways such as the omega-3 long chain polyunsaturated fatty acids. Given the potential benefits to the environment with regards to overfishing and the health prospects of increased consumption of these healthy fatty acids, producing these fatty acids in oilseeds is a desirable and worthy goal. In this review, we will describe the recent advances in this field along with some of the technical hurdles encountered thus far.

Negative confounding in the evaluation of toxicity: the case of methylmercury in fish and seafood

In observational studies, the presence of confounding [corrected] can distort the true association between an exposure and a toxic-effect outcome, if the confounding variable is not controlled for in the study design or analysis phase. While confounding is often assumed to occur in the same direction as the toxicant exposure, the relationship between the benefits and risks associated with fish and seafood consumption is a classic example of negative confounding: the exposure to methylmercury occurs with fish and seafood, which are also associated with beneficial nutrients, and the signs of mercury toxicity [corrected] Mercury and nutrients may affect the same epidemiological outcomes, but most studies addressing one of them have ignored the potential for negative confounding by the other. This article reviews the existing evidence of effects of both nutrient and contaminant intakes as predictors of neurodevelopmental and cardiovascular outcomes. Substantial underestimation of the effects of mercury toxicity and of fish benefits occurs from the lack of confounder adjustment and imprecision of the exposure parameters. Given this inherent bias in observational studies, regulatory agencies should reconsider current dietary advice in order to provide better guidance to consumers in making prudent choices to maintain a nutritious diet with seafood that is low in mercury concentrations. Attention should also be paid to the occurrence of negative confounding in other connections.

The influence of moderate and high dietary long chain polyunsaturated fatty acids (LCPUFA) on baboon neonate tissue fatty acids

Docosahexaenoic acid (DHA) and arachidonic acid (ARA) are now common ingredients in commercial infant formulas, however, the optimal levels have not been established. Our previous data showed that the current amount of DHA in U.S. term formulas, 0.3%w/w, is insufficient to normalize cerebral cortex DHA to levels in breastfed baboon neonate controls (Diau et al.: BMC Medicine 3: 11, 2005). Here, we report on the influence of higher formula DHA levels on 12-wk-old full-term baboon CNS and visceral organs. Fourteen nursery-reared baboons were randomized to one of three diets: control (C, no DHA-ARA); moderate LCPUFA (L, 0.33%DHA-0.67%ARA); high LCPUFA (L3, 1.00%DHA-0.67%ARA). DHA increased significantly in liver, heart, and plasma (all C < L < L3), RBC (C < L, L3), and CNS regions: precentral gyrus (C < L < L3), frontal cortex, inferior and superior colliculi, globus pallidus, and caudate (all C < L, L3). These data extend previous observations indicating that 1) tissue DHA is more sensitive to diet than ARA; 2) cerebral cortex DHA increases with higher levels of DHA than in present commercial formulas; and 3) basal ganglia and limbic system DHA saturate with levels of DHA currently available in formulas. These results imply that higher levels of DHA are necessary to normalize cortex DHA to those found in breastfed animals.

Long chain omega-3 polyunsaturated fatty acids in the treatment of psychiatric illnesses in children and adolescents

OBJECTIVE

Long chain omega-3 polyunsaturated fatty acids (LCn-3PUFA) are in increasing use in the general population to treat health problems. The objective of the current article is to review the evidence for the rationale and benefit of LCn-3PUFA in the treatment of common psychiatric disorders in children and adolescents.

METHODS

A search of Psychlit, PubMed and Cochrane Databases was conducted using the terms child, adolescent, bipolar, depression, psychosis, first-episode psychosis, schizophrenia, attention deficit hyperactivity disorder (ADHD), autism, psychiatric, omega-3, n-3, docosahexaenoic acid and eicosapentaenoic acid. Further studies were identified from the bibliographies of published reviews.

RESULTS

One small randomized controlled trial with LCn-3PUFA supplementation in depression in children found a small beneficial effect over placebo. Four placebo-controlled trials showed uncertain benefit of LCn-3PUFA for ADHD. Single placebo-controlled trials showed no benefit in autism or bipolar disorder. There is an absence of studies examining benefit for first-episode psychosis or schizophrenia in children and adolescents.

CONCLUSIONS

While children and adolescents are receiving LCn-3PUFA for a range of psychiatric indications, there is only evidence of likely benefit for unipolar depression.

Engineering Oilseed Plants for a Sustainable, Land-Based Source of Long Chain Polyunsaturated Fatty Acids

Numerous clinical studies have demonstrated the cardiovascular and mental health benefits of including very long chain omega-3 polyunsaturated fatty acids, namely eicospentaenoic acid (EPA) and docosohexaenoic acid (DHA) in the human diet. Certain fish oils can be a rich source of omega-3 long chain polyunsaturated fatty acids although processed marine oils are generally undesirable as food ingredients because of the associated objectionable flavors and contaminants that are difficult and cost-prohibitive to remove. Oilseed plants rich in omega-3 fatty acids, such as flax and walnut oils, contain only the 18-carbon omega-3 polyunsaturated fatty acid alpha-linolenic acid, which is poorly converted by the human body to EPA and DHA. It is now possible to engineer common omega-6 rich oilseeds such as soybean and canola to produce EPA and DHA and this has been the focus of a number of academic and industrial research groups. Recent advances and future prospects in the production of EPA and DHA in oilseed crops are discussed here.

Separation of risks and benefits of seafood intake

BACKGROUND

Fish and seafood provide important nutrients but may also contain toxic contaminants, such as methylmercury. Advisories against pollutants may therefore conflict with dietary recommendations. In resolving this conundrum, most epidemiologic studies provide little guidance because they address either nutrient benefits or mercury toxicity, not both.

OBJECTIVES

Impact on the same health outcomes by two exposures originating from the same food source provides a classical example of confounding. To explore the extent of this bias, we applied structural equation modeling to data from a prospective study of developmental methylmercury neurotoxicity in the Faroe Islands.

RESULTS

Adjustment for the benefits conferred by maternal fish intake during pregnancy resulted in an increased effect of the prenatal methylmercury exposure, as compared with the unadjusted results. The dietary questionnaire response is likely to be an imprecise proxy for the transfer of seafood nutrients to the fetus, and this imprecision may bias the confounder-adjusted mercury effect estimate. We explored the magnitude of this bias in sensitivity analysis assuming a range of error variances. At realistic imprecision levels, mercury-associated deficits increased by up to 2-fold when compared with the unadjusted effects.

CONCLUSIONS

These results suggest that uncontrolled confounding from a beneficial parameter, and imprecision of this confounder, may cause substantial underestimation of the effects of a toxic exposure. The adverse effects of methylmercury exposure from fish and seafood are therefore likely to be underestimated by unadjusted results from observational studies, and the extent of this bias will be study dependent.

Relationship between DHA status at birth and child problem behaviour at 7 years of age

Animal studies have demonstrated behavioural effects of long-chain polyunsaturated fatty acid (LC-PUFA) deficiencies and in humans, several psychiatric disorders have been linked to abnormal essential fatty acid metabolism. The aim of this study was to examine the relationship between LC-PUFA status at birth and the later development of problem behaviour. In a sample of 393 children, higher levels of docosahexaenoic acid (DHA) at birth were associated with lower levels of internalising problem behaviour at age 7 years. The association was markedly present in the infants fed with artificial formula (n=215, Beta=-0.32, P=0.000), but absent in the infants fed with human milk (n=170, Beta=0.11, P=0.325). The associations between arachidonic acid and internalising or externalising behaviour were neither large nor significant. The results suggest that perinatal DHA status may have long-term behavioural consequences. Therefore, we suggest to include measures of problem behaviour in future trials of LC-PUFA supplementation of mothers and/or infants.

Rapid growth in infancy: balancing the interests of the child

Low birth weight is associated with a number of immediate adverse consequences, and it has been assumed that "catch-up" growth is a "good thing" because "better" nutritional status is associated with greater childhood health and survival. The same thinking applies to infants who suffer malnutrition and growth faltering during weaning. Recent studies suggest that the rapid postnatal growth of babies is associated with an enhanced risk for obesity, diabetes, hypertension, cardiovascular disease and osteopenia in later life. If this is true, it has implications for our recommendations for infant feeding. Insights from evolutionary biology, life cycle theory, animal husbandry, epidemiology and comparative zoology suggest that the energetic feeding of underweight infants should be considered in the context of the whole life cycle and balance the interests of the child with its likely fortunes in adulthood. Before we revise our current recommendations, we must consider the meaning of catch-up growth, what it involves in terms of tissues gained (fat, muscle and bone) and to what degree association represents causation. In the meantime, it will be prudent to balance the short- and long-term interests of the child by endeavoring to (1) optimize maternal nutrition and health, to avoid low birth weight, (2) breast-feed ideally, (3) consider birth weight, gestation and future "nutritional environment" when making decisions about infant feeding, (4) use appropriate growth charts, (5) avoid excessive postnatal weight gain, (6) think about the whole life span and (7) extrapolate from animal studies cautiously.

A randomized trial of long-chain polyunsaturated fatty acid supplementation in infants with phenylketonuria

Forty-two infants (20 males, 22 females) with classical phenylketonuria (PKU) entered a prospective, double-blind, randomized study to investigate the effects on biochemical and physiological outcomes of a phenylalanine-free infant formula containing a fat blend supplemented with the long-chain polyunsaturated fatty acids (LC-PUFA), docosahexaenoic acid (DHA, C22:6 n-3), and arachidonic acid (AA, C20:4 n-6). Between entry and 20 weeks (entry and 1y) of age, median DHA levels in erythrocyte membrane phospholipids decreased by 15% (22%) in the LC-PUFA supplemented group (n=21) and by 61% (64%) in the control group (p<0.001; n=18). A dietary supply of LC-PUFA in infants with PKU prevents the decline in DHA levels associated with a diet supplying minimal sources of LC-PUFA. DHA status in turn, independent of diet, may influence the maturation of the visual system in infants with PKU.

Maternal dietary 22 : 6n-3 is more effective than 18 : 3n-3 in increasing the 22 : 6n-3 content in phospholipids of glial cells from neonatal rat brain

One of the debates in infant nutrition concerns whether dietary 18 : 3n-3 (linolenic acid) can provide for the accretion of 22 : 6n-3 (docosahexaenoic acid, DHA) in neonatal tissues. The objective of the present study was to determine whether low or high 18 : 3n-3 v. preformed 22 : 6n-3 in the maternal diet enabled a similar 22 : 6n-3 content in the phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI) and phosphatidylserine (PS) of glial cells from whole brain (cerebrum and cerebellum) of 2-week-old rat pups. At parturition, the dams were fed semi-purified diets containing either increasing amounts of 18 : 3n-3 (18 : 2n-6 to 18 : 3n-3 fatty acid ratio of 7.8 : 1, 4.4 : 1 or 1 : 1), preformed DHA, or preformed 20 : 4n-6 (arachidonic acid)+DHA. During the first 2 weeks of life, the rat pups from the respective dams received only their dam's milk. The fatty acid composition of the pups' stomach contents (dam's milk) and phospholipids from glial cells were quantified. The 20 : 4n-6 and 22 : 6n-3 content in the stomach from rat pups at 2 weeks of age reflected the fatty acid composition of the dam's diet. The 20 : 4n-6 content of PE and PS in the glial cells was unaffected by maternal diet treatments. Preformed 22 : 6n-3 in the maternal diet increased the 22 : 6n-3 content of glial cell PE and PS compared with maternal diets providing an 18 : 2n-6 to 18 : 3 n-3 fatty acid ratio of 7.8 : 1, 4.4 : 1 or 1 : 1 (P<0.0001). There was no significant difference in the 20 : 4n-6 and 22 : 6n-3 content of glial cell PC and PI among maternal diet treatments. It was concluded that maternal dietary 22 : 6n-3 is more effective than low or high levels of maternal dietary 18 : 3n-3 at increasing the 22 : 6n-3 content in PE and PS of glial cells from the whole brain of rat pups at 2 weeks of age. The findings from the present study have important implications for human infants fed infant formulas that are devoid of 22 : 6n-3.

Is docosahexaenoic acid, an n-3 long-chain polyunsaturated fatty acid, required for development of normal brain function? An overview of evidence from cognitive and behavioral tests in humans and animals

This review is part of a series intended for nonspecialists that will summarize evidence relevant to the question of whether causal relations exist between micronutrient deficiencies and brain function. Here, we focus on experiments that used cognitive or behavioral tests as outcome measures in experimental designs that were known to or were likely to result in altered brain concentrations of the n-3 fatty acid docosahexaenoic acid (DHA) during the perinatal period of "brain growth spurt." Experimental designs reviewed include observational breastfeeding studies and randomized controlled trials in humans and studies in rodents and nonhuman primates. This review is based on a large number of expert reviews and commentaries and on some 50 recent studies in humans and animals that have not yet been included in published reviews. Expert opinion regarding the strengths and weaknesses of the major experimental systems and uncertainties associated with interpreting results is summarized. On the basis of our reading of this literature, we conclude that evidence from several types of studies, particularly studies in animals, suggests that, within the context of specific experimental designs, changes in brain concentrations of DHA are positively associated with changes in cognitive or behavioral performance. Additional experimental information required to conclude that a causal association exists is discussed, as are uncertainties associated with applying results from specific experimental designs to the question of whether infant formula should be supplemented with DHA.

An introduction to dietary/supplemental omega-3 fatty acids for general health and prevention: Part II

The correction of a subtle nutritional deficiency that may reduce the risk of a future chronic disease is indeed a challenge. However, some specific examples in the past, such as the addition of folic acid to prevent neural tube defects and calcium and vitamin D to prevent osteoporosis, should provide some encouragement that some conditions can be prevented with the appropriate addition of a deficient compound. One of the most intriguing current and future impacts on public health may come from a higher intake of omega-3 fatty acids, such as alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). The omega-3 fatty acids continue to accumulate research that suggests that they may prevent a variety of diverse chronic diseases and potentially some acute clinical scenarios. In the first part of this article, the potential for these compounds to prevent certain cardiovascular conditions are discussed. In the second part, the potential for an impact in arthritis, numerous areas of cancer research, depression, maternal and child health, neurologic diseases, osteoporosis, and other medical disciplines are also briefly covered. The future appears bright for these agents, but specifically which conditions, who qualifies, testing, frequency, adequate sources, future trials, and numerous other questions need to be addressed and answered before the potential impact can catch up to the recent hype.

Long-chain polyunsaturated fatty acids in childhood developmental and psychiatric disorders

Both omega-3 and omega-6 long-chain PUFA (LC-PUFA) are crucial to brain development and function, but omega-3 LC-PUFA in particular are often lacking in modern diets in developed countries. Increasing evidence, reviewed here, indicates that LC-PUFA deficiencies or imbalances are associated with childhood developmental and psychiatric disorders including ADHD, dyslexia, dyspraxia, and autistic spectrum disorders. These conditions show a high clinical overlap and run in the same families, as well as showing associations with various adult psychiatric disorders in which FA abnormalities are already implicated, such as depression, other mood disorders, and schizophrenia. Preliminary evidence from controlled trials also suggests that dietary supplementation with LC-PUFA might help in the management of these kinds of childhood behavioral and learning difficulties. Treatment with omega-3 FA appears most promising, but the few small studies published to date have involved different populations, study designs, treatments, and outcome measures. Large-scale studies are now needed to confirm the benefits reported. Further research is also required to assess the durability of such treatment effects, to determine optimal treatment compositions and dosages, and to develop reliable ways of identifying those individuals most likely to benefit from this kind of treatment. Childhood developmental and psychiatric disorders clearly reflect multifactorial influences, but the study of LC-PUFA and their metabolism could offer important new approaches to their early identification and management. Heterogeneity and comorbidity are such, however, that a focus on specific traits or symptoms may prove more fruitful than an exclusive reliance on current diagnostic categories.