
Seafood Recommendations During Pregnancy: Article Abstracts
A Diet Quality Index for Pregnancy Detects Variation In Diet and Differences By Sociodemographic Factors
Bodnar LM and Siega-Riz AM
Objective: Methods currently used to assess nutritional status during pregnancy have limitations if one wishes to examine the overall quality of the diet. A Diet Quality Index for Pregnancy (DQI-P) was developed to reflect current nutritional recommendations for pregnancy and national dietary guidelines.
Design: Dietary intake was assessed during the second trimester using a food frequency questionnaire. The DQI-P includes eight components: % recommended servings of grains, vegetables and fruits, % recommendations for folate, iron and calcium, % energy from fat, and meal/snack patterning score. Scores can range from 0 to 80; each component contributed 10 points.
Setting: Two public prenatal clinics in central North Carolina. Subjects: N ¼ 2063 pregnant women who participated in the Pregnancy, Infection, and Nutrition (PIN) Study.
Results: The DQI-P quantitatively differentiated diets. The mean score for the population was 56.0 (standard deviation 12.0). Women who were .30 years old, .350% of poverty, nulliparous and high school graduates had significantly higher overall DQI-P scores. Higher percentages of recommended vegetable servings were consumed by higher-income, older and better-educated women. Greater percentages of recommended intakes of folate and iron were seen among black, low-income and nulliparous women. Higher iron intakes were also seen among women who graduated high school and were less than 30 years old. Other differences were observed for intake of fat and meal/snack pattern. Because this index was based on national recommendations, the DQI-P may be a useful tool for research and public health settings to evaluating overall diet quality of pregnant women.
Increased n-6 Polyunsaturated Fatty Acids Do Not Attenuate the Effects of Long-Chain n-3 Polyunsaturated Fatty Acids On Insulin Sensitivity or Triacylglycerol Reduction In Indian Asians
Brad LM, Lovegrove SS, Lesauvage SVM, Gower BA, Minihane AM, Williams CM, Lovegrove JA
Background: Indian Asians in Western countries have a higher rate of coronary artery disease than do the indigenous white populations, and this higher rate may be influenced by a dietary imbalance of n-6 and n-3 polyunsaturated fatty acids (PUFAs). Objective: The objective of the study was to test the hypothesis that a high background dietary intake of n-6PUFAattenuates the effects of fish-oil supplementation on insulin sensitivity and associated blood lipids of the metabolic syndrome.
Design: Twenty-nine Indian Asian men were recruited to participate in a 12-wk dietary intervention trial. Volunteers were randomly assigned to receive either a moderate or a high n-6 PUFA diet featuring modified oils and spreads over a 6-wk period. After this 6-wk period, both groups were supplemented with 4.0 g fish oil/d (2.5 g eicosapentaenoic acid +docosahexaenoic acid) for an additional 6 wk in combination with the dietary treatment. Volunteers participated in a postprandial study and an insulin sensitivity test after the 6-wk dietary intervention and again after the fish-oil supplementation period.
Results: There was no significant time -treatment interaction for blood lipids or insulin action after dietary intervention with the moderate or high n_6PUFAdiets in combination with fish oil. After the 6-wk period of fish oil supplementation, fasting and postprandial plasma triacylglycerol concentrations decreased significantly.
Conclusion: The background dietary n-6 PUFA concentration did not modulate the effect of fish-oil supplementation on blood lipids or measures of insulin sensitivity in this ethnic group.
Separation of Risks and Benefits of Seafood Intake
Budtz-Jørgensen E, Grandjean P, Weihe P
Background: Fish and seafood provide important nutrients but may also contain toxic contaminants, such as methyl mercury. 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 methyl mercury 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 methyl mercury 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 methyl mercury 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.
n-3 Fatty Acids and Cognitive and Visual Acuity Development: Methodologic and Conceptual Considerations
Cheatham CL, Colombo J, Carlson SE
Several randomized clinical studies in infants born preterm and at term have explored the effects on visual acuity development of postnatal supplementation with various sources of docosahexaenoic acid (DHA). Higher visual acuity after DHA supplementation is a consistent finding in infants born preterm. For infants born at term, the results are less consistent and are better explained by differences in sensitivity of the visual acuity test (electrophysiologic tests being more sensitive than subjective tests) or by differences in the amount of DHA included in the experimental formula. Differences in the sensitivity of the test may also be relevant in discussions of whether the effects of DHA on visual acuity are transient or persistent. A smaller number of studies have attempted to study the effects of DHA on cognitive development. The major focus of this article is to review the types of methods that have been used to evaluate the effects of DHA on cognition and to provide the rationale for measures that are a better conceptual fit. Research is needed 1) to probe the effects of variable DHA exposure on infant and child development, 2) to measure outcomes that better relate to preschool and school-age cognitive function, and 3) to reinforce, and in some cases demonstrate, links between specific infant and preschool measures of cognitive development. We strongly encourage collaborations with developmental cognitive neuroscientists to facilitate these research goals.
Directly Quantitated Dietary (n-3) Fatty Acid Intakes of Pregnant Canadian Women Are Lower Than Current Dietary Recommendations
Denomme J, Stark KD, Holub BJ
During pregnancy, (n-3) PUFA are incorporated into fetal brain and retinal lipids. Docosahexaenoic acid [DHA, 22:6(n-3)], in particular, is required physiologically for optimal development and function of the central nervous system. Maternal intake of (n-3) PUFA must be sufficient to maintain maternal tissues stores and meet fetal accruement. Recommendations for pregnant women include an Acceptable Macronutrient Distribution Range (AMDR) of 0.6-1.2% of energy for (n-3) PUFA intake in the current Dietary Reference Intakes, and _300 mg/d of DHA suggested by the International Society for the Study of Fatty Acids and Lipids working group. The present study directly quantitated the (n-3) PUFA intake, including DHA, of pregnant, Canadian women (n -2 ) in their 2nd and 3rd trimester. Fatty acid intakes were quantitated in triplicate by lipid extraction and GLC of 3-d duplicate food collections calibrated with an internal standard before homogenization. Total fat intakes were also estimated using dietary analysis software from simultaneous 3-d food records to corroborate biochemical analyses. The mean (n-3) PUFA intake was 0.57 ± 0.06% of energy, with 65% of the women below the AMDR. The mean DHA intake was 82 ± 33 mg/d, with 90% of the women consuming ±300 mg/d. Nutritional education of pregnant women to ensure adequate intakes of (n-3) PUFA for optimal health of mother and child and the inclusion of DHA in prenatal vitamins may be pertinent.
Omega-3 Fatty Acids and Perinatal Depression: A Review of the Literature and Recommendations for Future Research
Freeman MP
Introduction: Perinatal depression refers to major depression in the context of pregnancy and postpartum. In consideration of its prevalence and consequences, the treatment and prevention of perinatal depression should be important public health priorities. Omega-3 fatty acids are attractive for consideration in perinatal women, due to known health benefits for the mother and baby. Antidepressant medications may pose risks in utero and in breastfeeding.
Methods: MEDLINE and manual searches were conducted.
Results: Epidemiological and preclinical data support a role of omega-3 fatty acids in perinatal depression. Two studies failed to support a role of omega-3 fatty acids for postpartum depression prophylaxis, although one included a small sample, and the other utilized a low dosage. Two pilot studies suggest good tolerability and potential efficacy in the acute treatment of perinatal depression.
Conclusions: Further research studies are warranted to determine the role of omega-3 fatty acids in the treatment of perinatal depression.
Randomized dose-ranging pilot trial of omega-3 fatty acids for postpartum depression
Freeman MP, Hibbeln JR, Wisner KL, Brumbach BH, Watchman M, Gelenberg AJ.
Objective: Postpartum depression (PPD) affects 10-15% of mothers. Omega-3 fatty acids are an intriguing potential treatment for PPD.
Method: The efficacy of omega-3 fatty acids for PPD was assessed in an 8-week dose-ranging trial. Subjects were randomized to 0.5 g/day (n ¼ 6), 1.4 g/day (n ¼ 3), or 2.8 g/day (n ¼ 7).
Results: Across groups, pretreatment Edinburgh Postnatal Depression Scale (EPDS) and Hamilton Rating Scale for Depression (HRSD) mean scores were 18.1 and 19.1 respectively; post-treatment mean scores were 9.3 and 10.0. Percent decreases on the EPDS and HRSD were 51.5% and 48.8%, respectively; changes from baseline were significant within each group and when combining groups. Groups did not significantly differ in pre- or post-test scores, or change in scores. The treatment was well tolerated.
Conclusion: This study was limited by small sample size and lack of placebo group. However, these results support further study of omega-3 fatty acids as a treatment for PPD.
Omega-3 Fatty Acids: Evidence Basis for Treatment and Future Research In Psychiatry
Freeman MP, Hibbeln JR, Wisner KL, Davis JM, Mischoulon D, Peet M, Keck PE Jr, Marangell LB, Richardson AJ, Lake J, Stoll AL.
Objective: To determine if the available data support the use of omega-3 essential fatty acids (EFA) for clinical use in the prevention and/or treatment of psychiatric disorders.
Participants: The authors of this article were invited participants in the Omega-3 Fatty Acids Subcommittee, assembled by the Committee on Research on Psychiatric Treatments of the American Psychiatric Association (APA). EVIDENCE: Published literature and data presented at scientific meetings were reviewed. Specific disorders reviewed included major depressive disorder, bipolar disorder, schizophrenia, dementia, borderline personality disorder and impulsivity, and attention-deficit/hyperactivity disorder. Meta-analyses were conducted in major depressive and bipolar disorders and schizophrenia, as sufficient data were available to conduct such analyses in these areas of interest.
Consensus Process: The subcommittee prepared the manuscript, which was reviewed and approved by the following APA committees: the Committee on Research on Psychiatric Treatments, the Council on Research, and the Joint Reference Committee.
Conclusions: The preponderance of epidemiologic and tissue compositional studies supports a protective effect of omega-3 EFA intake, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in mood disorders. Meta-analyses of randomized controlled trials demonstrate a statistically significant benefit in unipolar and bipolar depression (p = .02). The results were highly heterogeneous, indicating that it is important to examine the characteristics of each individual study to note the differences in design and execution. There is less evidence of benefit in schizophrenia. EPA and DHA appear to have negligible risks and some potential benefit in major depressive disorder and bipolar disorder, but results remain inconclusive in most areas of interest in psychiatry. Treatment recommendations and directions for future research are described. Health benefits of omega-3 EFA may be especially important in patients with psychiatric disorders, due to high prevalence rates of smoking and obesity and the metabolic side effects of some psychotropic medications.
Omega-3 Long-Chain Polyunsaturated Fatty Acids in Older Children
Heird WC
In toto, the study of Beblo et al adds considerably to an existing body of data suggesting that omega-3 LC-PUFA may be conditionally essential for infants and children with PKU. This, presumably, is because the usual PKU diet is low in protein and, hence, low in the common dietary sources of omega-3 LC-PUFA (e.g., fish, meat, eggs). This also appears to be true for other nutrients; for example, formulas for patients with PKU are supplemented with several essential trace minerals and vitamins that have been shown to be low in low protein diets or poorly available from these diets. The improvement of older children with PKU because of omega-3 LC-PUFA supplementation, without changes in plasma phenylalanine concentration, suggests that still other groups might benefit from dietary omega-3 LC-PUFA. Certainly, the brain continues to grow well beyond infancy, and there likely is considerable turnover of brain components, including DHA, after adult size is reached; thus, there may be benefits of omega-3 LC-PUFA supplementation, not only during infancy and early childhood, but also, perhaps, during adolescence and adulthood. Currently, evidence that children with PKU might benefit from omega-3 LC-PUFA supplementation, perhaps as a component of their low phenylalanine formula, is reasonably strong. However, whether this supplement should be EPA,DHA, or perhaps both, as studied by Beblo et al, is not clear. The amount of these fatty acids that should be provided also is not clear. An 8% increase in plasma phospholipid EPA content, as reported by Beblo et al, seems somewhat excessive. Further, considering the 27% decrease in plasma phospholipid AA observed by Beblo et al, the supplement perhaps should also include omega-6 LC-PUFA.
Maternal Seafood Consumption In Pregnancy and Neurodevelopmental Outcomes In Childhood
(ALSPAC study): An Observational Cohort Study
Hibbeln JR, Davis JM, Steer C, Emmett P, Rogers I, Williams C, Golding J
Summary: Background Seafood is the predominant source of omega-3 fatty acids, which are essential for optimum neural development. However, in the USA, women are advised to limit their seafood intake during pregnancy to 340 g per week. We used the Avon Longitudinal Study of Parents and Children (ALSPAC) to assess the possible benefits and hazards to a child's development of different levels of maternal seafood intake during pregnancy.
Methods: 1 875 pregnant women completed a food frequency questionnaire assessing seafood consumption at 32 weeks' gestation. Multivariable logistic regression models including 28 potential confounders assessing social disadvantage, perinatal, and dietary items were used to compare developmental, behavioural, and cognitive outcomes of the children from age 6 months to 8 years in women consuming none, some (1-340 g per week), and >340 g per week.
Findings: After adjustment, maternal seafood intake during pregnancy of less than 340 g per week was associated with increased risk of their children being in the lowest quartile for verbal intelligence quotient (IQ) (no seafood consumption, odds ratio [OR] 1·48, 95% CI 1·16-1·90; some, 1·09, 0·92-1·29; overall trend, p=0·004), compared with mothers who consumed more than 340 g per week. Low maternal seafood intake was also associated with increased risk of suboptimum outcomes for prosocial behaviour, fine motor, communication, and social development scores. For each outcome measure, the lower the intake of seafood during pregnancy, the higher the risk of suboptimum developmental outcome. Interpretation Maternal seafood consumption of less than 340 g per week in pregnancy did not protect children from adverse outcomes; rather, we recorded beneficial effects on child development with maternal seafood intakes of more than 340 g per week, suggesting that advice to limit seafood consumption could actually be detrimental. These results show that risks from the loss of nutrients were greater than the risks of harm from exposure to trace contaminants in 340 g seafood eaten weekly.
Dietary Intake of Fatty Acids and Fish In Relation to Cognitive Performance At Middle Age
Kalmijn S, van Boxtel MPJ, Ocké M, Verschuren WMM, Kromhout D, Launer LJ
Objective: To examine the associations of fatty acid and fish intake with cognitive function.
Methods: Data are from a cross-sectional population-based study among 1,613 subjects ranging from 45 to 70 years old. From 1995 until 2000, an extensive cognitive battery was administered and compound scores were constructed for memory, psychomotor speed, cognitive flexibility (i.e., higher order information processing), and overall cognition. A self-administered food frequency questionnaire was used to assess habitual food consumption. The risk of impaired cognitive function (lowest 10% of the compound score) according to the energy adjusted intake of fatty acids was assessed with logistic regression, adjusting for age, sex, education, smoking, alcohol consumption, and energy intake.
Results: Marine omega-3 polyunsaturated fatty acids (PUFA) (eicosapentaenoic acid and docosahexaenoic acid) were inversely related to the risk of impaired overall cognitive function and speed (per SD increase: OR = 0.81, 95% CI 0.66 to 1.00 and OR = 0.72, 95% CI 0.57 to 0.90). Results for fatty fish consumption were similarly inverse. Higher dietary cholesterol intake was significantly associated with an increased risk of impaired memory and flexibility (per SD increase: OR =1.27, 95% CI 1.02 to 1.57 and OR =1.26, 95% CI 1.01 to 1.57). Per SD increase in saturated fat intake, the risk of impaired memory, speed, and flexibility was also increased, although not significantly.
Conclusions: Fatty fish and marine omega-3 PUFA consumption was associated with a reduced risk and intake of cholesterol and saturated fat with an increased risk of impaired cognitive function in this middle-aged population.
Plasma Fatty Acid Composition Is Associated With the Metabolic Syndrome and Low-Grade Inflammation In Overweight Adolescents
Klein-Platat C, Drai J, Oujaa M, Schlienger JL, Simon C
Background: Together with adiposity, plasma fatty acid (FA) composition can modulate the development of the metabolic syndrome (MS).
Objective: Our aim was to investigate the relations of FA composition in plasma phospholipids and cholesterol esters (CEs) with weight status, MS, and inflammation in adolescents.
Design: Plasma FA composition was measured by gas-liquid chromatography in 120 (60 normal-weight and 60 overweight) 12-y-old adolescents. We also measured the presence of MS, insulin resistance with the homeostasis model assessment, and interleukin 6 and C-reactive protein concentrations in the adolescents.
Results: MS was present in 25% of the overweight adolescents but in none of the normal-weight adolescents. Compared with overweight adolescents, normal-weight adolescents had lower saturated FAs (SFAs) in both phospholipids (P <0.001) and CEs (P < 0.01) and higher docosahexaenoic acid in phospholipids (P <0.001). In overweight subjects, FA composition was associated with MS features independent of body fat. The odds ratios of MS for a 0.1 increase in the ratio of polyunsaturated FAs (PUFA) to SFAs (PUFA:SFA) were 0.91 in phospholipids (P<0.03) and 0.90 in CEs (P<0.06). In phospholipids, PUFA:SFA and linoleic acid were associated positively with HDL cholesterol (P <0.01 for both). PUFA:SFA in phospholipids and CEs were associated inversely with interleukin 6 (P < 0.05 for both). Eicosapentaenoic acid in phospholipids (P <0.06) and CEs (P<0.05) and linolenic acid in CEs (P <0.05) were inversely related to C-reactive protein. These relations remained significant after adjustment for the waist-to-hip ratio. No significant relation between FA composition and the homeostasis model assessment was observed.
Conclusions: Plasma FA composition is associated with weight status in healthy adolescents. High intake of long-chain PUFAs, especially n-3 PUFAs, may protect obese subjects against MS and low-grade inflammation as early as adolescence.
Dietary Fat Intakes for Pregnant and Lactating Women
Koletzko B, ICetin I, Brenna JT for the Perinatal Lipid Intake Working Group
Dietary fat intake in pregnancy and lactation affects pregnancy outcomes and child growth, development and health. The European Commission charged the research project PERILIP, jointly with the Early Nutrition Programming Project, to develop recommendations on dietary fat intake in pregnancy and lactation. Literature reviews were performed and a consensus conference held with international experts in the field, including representatives of international scientific associations. The adopted conclusions include: dietary fat intake in pregnancy and lactation (energy%) should be as recommended for the general population; pregnant and lactating women should aim to achieve an average dietary intake of at least 200 mg DHA/d; intakes of up to 1 g/d DHA or 2·7 g/d n-3 long-chain PUFA have been used in randomized clinical trials without significant adverse effects; women of childbearing age should aim to consume one to two portions of sea fish per week, including oily fish; intake of the DHA precursor, a-linolenic acid, is far less effective with regard to DHA deposition in fetal brain than preformed DHA; intake of fish or other sources of long-chain n-3 fatty acids results in a slightly longer pregnancy duration; dietary inadequacies should be screened for during pregnancy and individual counselling be offered if needed.
Fish and Shellfish As Dietary Sources of Methylmercury and the Omega-3 Fatty Acids, Eicosahexaenoic Acid and Docosahexaenoic Acid: Risks and Benefits.
Mahaffey KR
Fish and shellfish supply the human diet with not only complex nutrients including the omega-3 fatty acids, but also highly toxic chemicals including methylmercury. The dietary essential fatty acids are linoleic and alpha-linolenic acid. Two omega-3 fatty acids with longer carbon chains, eicosahexaenoic acid (EPA) and docosahexaenoic acid (DHA), can be synthesized in humans from alpha-linolenic precursors. Though not required in the diet per se, EPA and DHA have important roles in metabolism. The almost exclusive source of preformed dietary DHA is fish and shellfish. These foods are also an important source of EPA. In marked contrast to the benefits of fish and shellfish as sources of preformed omega-3 fatty acids, fish and shellfish are almost exclusively the dietary source of methylmercury. Fortunately, these chemicals are not uniformly distributed across many species of fish and shellfish. The purpose of this article is to provide information on the comparative distribution of these chemicals and nutrients to help groups formulating dietary recommendations.
Fish Intake, Contaminants and Human Health: Evaluating the Risks and the Benefits
Mozaffarian D and Rimm EB
Context: Fish (finfish or shellfish) may have health benefits and also contain contaminants, resulting in confusion over the role of fish consumption in a healthy diet.
Evidence Acquisition : We searched MEDLINE, governmental reports, and metaanalyses, supplemented by hand reviews of references and direct investigator contacts, to identify reports published through April 2006 evaluating (1) intake of fish or fish oil and cardiovascular risk, (2) effects of methylmercury and fish oil on early neurodevelopment, (3) risks of methylmercury for cardiovascular and neurologic outcomes in adults, and (4) health risks of dioxins and polychlorinated biphenyls in fish. We concentrated on studies evaluating risk in humans, focusing on evidence, when available, from randomized trials and large prospective studies. When possible, metaanalyses were performed to characterize benefits and risks most precisely.
Evidence Synthesis: Evidence Synthesis Modest consumption of fish (eg, 1-2 servings/wk), especially species higher in the n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), reduces risk of coronary death by 36% (95% confidence interval, 20%-50%; P_.001) and total mortality by 17% (95% confidence interval, 0%- 32%; P=.046) and may favorably affect other clinical outcomes. Intake of 250 mg/d of EPA and DHA appears sufficient for primary prevention. DHA appears beneficial for, and low-level methylmercury may adversely affect, early neurodevelopment. Women of childbearing age and nursing mothers should consume 2 seafood servings/wk, limiting intake of selected species. Health effects of low-level methylmercury in adults are not clearly established; methylmercury may modestly decrease the cardiovascular benefits of fish intake. A variety of seafood should be consumed; individuals with very high consumption (_5 servings/wk) should limit intake of species highest in mercury levels. Levels of dioxins and polychlorinated biphenyls in fish are low, and potential carcinogenic and other effects are outweighed by potential benefits of fish intake and should have little impact on choices or consumption of seafood (women of childbearing age should consult regional advisories for locally caught freshwater fish).
Conclusions: For major health outcomes among adults, based on both the strength of the evidence and the potential magnitudes of effect, the benefits of fish intake exceed the potential risks. For women of childbearing age, benefits of modest fish intake, excepting a few selected species, also outweigh risks.
Seafood Choices: Balancing Benefits and Risks
Committee on Nutrient Relationships in Seafood: Selections to Balance Benefits and Risks, Malden C. Nesheim MC and Yaktine AL, Editors
The fragmented information that consumers receive about the nutritional value and health risks associated with fish and shellfish can result in confusion or misperceptions about these food sources. Consumers are therefore confronted with a dilemma: they are told that seafood is good for them and should be consumed in large amounts, while at the same time the federal government and most states have issued advisories urging caution in the consumption of certain species or seafood from specific waters.
Seafood Choices carefully explores the decision-making process for selecting seafood by assessing the evidence on availability of specific nutrients (compared to other food sources) to obtain the greatest nutritional benefits. The book prioritizes the potential for adverse health effects from both naturally occurring and introduced toxicants in seafood; assesses evidence on the availability of specific nutrients in seafood compared to other food sources; determines the impact of modifying food choices to reduce intake of toxicants on nutrient intake and nutritional status within the U.S. population; develops a decision path for U.S. consumers to weigh their seafood choices to obtain nutritional benefits balanced against exposure risks; and identifies data gaps and recommendations for future research. The information provided in this book will benefit food technologists, food manufacturers, nutritionists, and those involved in health professions making nutritional recommendations.
Maternal Fish Consumption, Hair Mercury and Infant Cognition In a U.S. Cohort
Oken E, Wright RO, Kleinman KP, Bellinger D, Amarasiriwardena CJ, Hu H, Rich-Edwards JW, Gillman MW
Fish and other seafood may contain organic mercury but also beneficial nutrients such as n-3 polyunsaturated fatty acids. We endeavored to study whether maternal fish consumption during pregnancy harms or benefits fetal brain development. We examined associations of maternal fish intake during pregnancy and maternal hair mercury at delivery with infant cognition among 135 mother-infant pairs in Project Viva, a prospective U.S. pregnancy and child cohort study. We assessed infant cognition by the percent novelty preference on visual recognition memory (VRM) testing at 6 months of age. Mothers consumed an average of 1.2 fish servings per week during the second trimester. Mean maternal hair mercury was 0.55 ppm, with 10% of samples > 1.2 ppm. Mean VRM score was 59.8 (range, 10.9-92.5). After adjusting for participant characteristics using linear regression, higher fish intake was associated with higher infant cognition. This association strengthened after adjustment for hair mercury level: For each additional weekly fish serving, offspring VRM score was 4.0 points higher [95% confidence interval (CI), 1.3 to 6.7]. However, an increase of 1 ppm in mercury was associated with a decrement in VRM score of 7.5 (95% CI, -13.7 to -1.2) points. VRM scores were highest among infants of women who consumed > 2 weekly fish servings but had mercury levels ? 1.2 ppm. Higher fish consumption in pregnancy was associated with better infant cognition, but higher mercury levels were associated with lower cognition. Women should continue to eat fish during pregnancy but choose varieties with lower mercury contamination.
Maternal Parity and Diet (n-3) Polyunsaturated Fatty Acid Concentration Influence Accretion of Brain Phospholipid Docosahexaenoic Acid In Developing Rats
Ozias MK, Carlson SE, Levant B
The long-chain PUFA, docosahexaenoic acid [22:6(n-3), DHA], a major component of neuronal membrane phospholipids, accumulates in brain during late prenatal and early neonatal development and is essential for optimal attentional and cognitive function. Because all nutrition is supplied to the developing fetus/neonate by the mother and maternal DHA status is affected by parity, this study examined the effects of maternal diet and parity on DHA accretion in the developing brain. Whole brain total phospholipid fatty acid composition was determined by TLC and GC in weanling male Long-Evans rats (n=5) from the 1st, 2nd, 3rd, or 4th litters of dams fed diets containing ?-linolenic acid (ALA), containing ALA and preformed DHA (ALA + DHA), or lacking ALA (low-ALA). First-litter low-ALA offspring exhibited a decrease in phospholipid fatty acid DHA content to 68% of 1st-litter ALA pups. DHA in 2nd-litter low-ALA pups was further decreased to 55% of 1st-litter ALA pups, but further decreases were not observed in subsequent litters. DHA levels increased 15-20% in 2nd to 4th-litter ALA + DHA pups and 11% in 4th-litter ALA pups compared with 1st-litter ALA pups. These findings demonstrate that maternal diet and parity interact to affect offspring brain DHA status and suggest that maternal multiparity may place offspring at greater risk of decreased accretion of brain DHA if the maternal diet contains insufficient (n-3) PUFA.
Sources of the Very-Long-Chain Unsaturated Omega-3 Fatty Acids: Eicosapentaenoic Acid and Docosahexaenoic Acid
Racine RA and Deckelbaum RJ
Purpose of review: We assess the toxicological, environmental and economic aspects of sources of fish oil and omega-3 fatty acids (n-3 fatty acids).
Recent findings: Fish oils are the most common source of the very-long-chain n-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid, which have protective and beneficial effects on conditions such as cardiovascular, inflammatory, or neurological diseases. Fish oils can also be potential hazards for human health, because of external pollutants bioaccumulating in fish. Wild and farmed fish are generally both similar in n-3 fatty acid content but may vary in terms of potential toxins. Reports on aquaculture and fish oil production, and other sources of n-3 fatty acids, are reviewed to assess which may be more suitable economically and ecologically for higher fish oil production and availability.
Summary: Although today's fish oil production meets demand, it is likely that this will not be able to increase without adversely affecting the world's wild stock of fish. Neither wild nor farmed fish constitute a sustainable source of n-3 fatty acids for supplementation. Solutions may be found through the evolution of the current aquaculture system or the utilization of alternative manufacturing sources for increasing intakes of n-3 fatty acids.
Maternal Nutrition and Optimal Infant Feeding Practices: Executive Summary
Raiten DJ, Kalhan SC, Hay WW Jr.
Much recent attention has been paid to the effect of the fetal environment on not only healthy birth outcomes but also long-term health outcomes, including a role as an antecedent to adult diseases.
A major gap in our understanding of these relations, however, is the effect of maternal nutrition and nutrient transport on healthy fetal growth and development. In addition, this gap precludes evidence-based recommendations about how to best feed preterm infants. The biological role of the mother and the effect of her nutritional status on infant feeding extend to postnatal infant feeding practices. Currently, evidence is incomplete about not only the composition of human milk, but also the maternal nutritional needs to support extended lactation and the appropriate nutrient composition of foods that will be used to complement breastfeeding at least through the first year of life. Consequently, a conference, organized by the National Institute of Child Health and Human Development, the National
Institutes of Health Office of Dietary Supplements, and the US Department of Agriculture Children's Nutrition Research Center was held to explore current knowledge and develop a research agenda to address maternal nutrition and infant feeding practices. These proceedings contain presentations about the effect of maternal nutrition and the placental environment on fetal growth and birth outcomes, as well as issues pertaining to feeding preterm and full-term infants.
Maternal and Perinatal Roles In Preterm Birth Long-Chain Fatty Acids: Possible Roles In Preterm Birth
Reece MS, McGregor JA, Allen KGD, Harris MA
OBJECTIVE: We conducted a case-control study to evaluate whether maternal and fetal m-3 and m-6 essential fatty acid status play possible roles in the pathogenesis of preterm birth.
STUDY DESIGN: Essential fatty acid status in blood and trophoblast tissues was measured in (1) women and their newborns with spontaneous preterm birth and (2) control women and newborns at 34 weeks' gestation (maternal blood) and at term delivery.
RESULTS: Thirty-seven preterm (mean gestational age 34 weeks) and 34 control mother-baby dyads (gestational age 40 weeks) were evaluated. The maternal percent of total arachidonic acid in red blood cells and plasma was increased in preterm cases versus controls at delivery (3.8- and 1.6-fold, respectively, p < 0.05). Maternal red blood cell eicosapentaenoic acid (1.98 ± 0.15, p < 0.0001) and m-3Ao-6 ratios (0.58 ± 0.22, p < 0.009) were lower in preterm cases than in controls at delivery (4.64 + 0.32 and 1.27 ± 0.12, respectively). Docosapentaenoic acid, a marker of ~o-3 essential fatty acid deficiency, was higher in preterm maternal red blood cells (1.26 ± 0.18, p < 0.0001) and amnion (1.27 ± 0.19, p < 0.001) compared with term controls (0.12 ± 0.07 and 0.58 ± 0.13, respectively).
CONCLUSION: Women delivered preterm demonstrated higher arachidonic acid and docosapentaneoic acid levels in maternal blood and trophoblast tissue than did women delivered at term. This suggests (1) altered essential fatty acid intake or metabolism in a portion of women delivered preterm and (2) increased maternal red blood cell arachidonic acid is associated with an increased risk of preterm birth.










