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1.
The long-chain polyunsaturated fatty acid (LC-PUFA) intake in preterm infants is crucial for normal central nervous system development and has the potential for long-lasting effects that extend beyond the period of dietary insufficiency. While much attention has focused on improving their nutritional intake, many premature infants do not receive an adequate DHA supply. We demonstrate that enterally fed premature infants exhibit daily DHA deficit of 20 mg/kg.d, representing 44% of the DHA that should have been accumulated. Furthermore, the DHA content of human milk and current preterm formulas cannot compensate for an early DHA deficit which may occur during the first month of life. We recommend breast-feeding, which supplies preformed LC-PUFA, as the preferred method of feeding for preterm infants. However, to fulfill the specific DHA requirement of these infants, we recommend increasing the DHA content of human milk either by providing the mothers with a DHA supplement or by adding DHA directly to the milk. Increasing the DHA content above 1% total fatty acids appears to be safe and may enhance neurological development particularly that of infants with a birth weight below 1250 g. We estimate that human milk and preterm formula should contain 1.5% of fatty acid as DHA to prevent the appearance of a DHA deficit and to compensate for the early DHA deficit. 相似文献
2.
BackgroundLCn-3PUFA comprised of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) offer cardioprotection involving a decrease in coagulant activity; however, the evidence is equivocal. We have previously demonstrated that the acute (24 h) effects and chronic (4 weeks) effects of LCn-3PUFA supplementation on platelet aggregation in human subjects are sex specific. This study investigated the mechanisms of the sex-dependent effects of LCn-3PUFA with 4 weeks supplementation of EPA-rich vs. DHA-rich oils on procoagulant and platelet activity in healthy subjects. DesignA double-blinded, placebo-controlled randomised trial was conducted in 94 healthy adults: male ( n=41) and female ( n=53). Platelet coagulation parameters including factors I, II, V, VII, VIII, IX, X, vWF:Ag and endogenous thrombin potential were measured at baseline and 4 weeks postsupplementation with EPA-rich or DHA-rich oil capsules. ResultsWe have previously reported that platelet aggregation is specifically reduced by supplementation with EPA in males and DHA in females. This sex-specific effect was also observed for decreases in plasma levels of Factor II (−7.9±3.8%, P=.026), Factor V (−6.5±4.5%, P=.022) and vWF:Ag (−7.3±2.1%, P=.034) and was most pronounced in males supplemented with EPA. In contrast, DHA-mediated reduction in platelet aggregation in females was not accompanied by any significant changes in the coagulation parameters tested. ConclusionSignificant interactions between sex and specific LCn-3PUFA exist to reduce procoagulant activity differentially in males vs. females and could have profound effects on managing risk of thrombotic disease. 相似文献
3.
Blood levels of polyunsaturated fatty acids (PUFA) are considered biomarkers of status. Alpha-linolenic acid, ALA, the plant omega-3, is the dietary precursor for the long-chain omega-3 PUFA eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA). Studies in normal healthy adults consuming western diets, which are rich in linoleic acid (LA), show that supplemental ALA raises EPA and DPA status in the blood and in breast milk. However, ALA or EPA dietary supplements have little effect on blood or breast milk DHA levels, whereas consumption of preformed DHA is effective in raising blood DHA levels. Addition of ALA to the diets of formula-fed infants does raise DHA, but no level of ALA tested raises DHA to levels achievable with preformed DHA at intakes similar to typical human milk DHA supply. The DHA status of infants and adults consuming preformed DHA in their diets is, on average, greater than that of people who do not consume DHA. With no other changes in diet, improvement of blood DHA status can be achieved with dietary supplements of preformed DHA, but not with supplementation of ALA, EPA, or other precursors. 相似文献
4.
The accretion of docosahexaenoic acid (DHA) in membranes of the central nervous system is required for the optimum development of retina and brain functions. DHA status is determined by the dietary intake of n-3 polyunsaturated fatty acids (PUFA), both the metabolic precursor α-linolenic acid (α-LNA) and DHA. Clinical studies have shown that feeding term or premature infants with formula low in total n-3 PUFA may alter the maturation of visual acuity. Moreover, feeding infants over the first 6 mon of life with formula containing adequate α-LNA, but no DHA, did not sustain the same cerebral accretion of DHA as that of breast-fed infants. Whether lower DHA accretion in brain of formula-fed term infants impairs neurophysiological performances is not clearly established. Contradictory data have been published, possibly owing to confounding factors such as maternal intakes and/or genetic variations in PUFA metabolism. Nevertheless, a large corpus of data is in favor of the recommendation of regular dietary intakes of DHA (during at least the first 6 mon of life) and suggest that DHA should be added in formulas at the level generally found in human milk (0.2-0.3 wt% of total fatty acids). The maternal intake of n-3 PUFA during pregnancy and lactation is also crucial, since the n-3 PUFA are provided during perinatal development through placental transfer and maternal milk, which determines the DHA status of the newborn and consequently impacts on post-natal development of brain and visual functions. Whether more clinical studies are needed to control and improve the impact of DHA maternal intakes on the progeny’s neurodevelopment, several commissions recommended by precaution that DHA average intake for pregnant and lactating women should be of 200-300 mg/day. 相似文献
5.
BackgroundDietary supplementation with omega-3 fatty acids has been associated with reduced incidence in thrombotic events. In addition, administration of n-3 polyunsaturated fatty acids (PUFAs) has been shown to rectify elevated platelet microparticle (MP) number and procoagulant activity in post myocardial infarction patients. However, it is unknown whether supplementation can alter these parameters in healthy individuals and if such effects are immediate or require long-term supplementation. We have previously demonstrated a gender-specific effect of LCn-3PUFA supplementation on platelet aggregation in healthy human subjects. Here we extend these findings to include the acute effects of supplementation with EPA- or DHA-rich oils on circulating MP levels and activity in healthy subjects. DesignA placebo-controlled trial was conducted in healthy males and females ( n=30). MP activity, MP levels and platelet aggregation were measured at 0 and 24 h postsupplementation with either a placebo or EPA- or DHA-rich oil. ResultsBoth EPA and DHA effectively reduced platelet aggregation at 24 h postsupplementation relative to placebo (?13.3%, P=.006 and ?11.9%, P=.016, respectively), but only EPA reduced MP activity (?19.4%, P=.003). When grouped by gender, males showed a similar reduction in both platelet aggregation and MP activity (?20.5%, P=.008; ?22%, P=.008) following EPA, while females showed significantly reduced platelet aggregation (?13.7%, P=.04) but not MP activity after DHA only. ConclusionEPA and DHA exert gender-dependent effects on platelet aggregation and platelet MP activity, but not on MP levels. With respect to thrombotic disease risk, males may benefit more from EPA supplementation. 相似文献
6.
Formula supplemented with docosahexaenoic acid (DHA) improves retinal function of preterm infants but the optimal dose is unknown. In a randomized controlled trial we examined the effect of increasing the DHA concentration of human milk and formula on circulating fatty acids of preterm infants. Infants born <33 weeks gestation were fed high-DHA milk (1% total fat as DHA) or standard-DHA milk (0.2-0.3% DHA) until reaching their estimated due date (EDD). Milk arachidonic acid (AA) concentration was approximately 0.5% for both groups. At EDD, erythrocyte membrane phospholipid DHA was elevated in the high-DHA group compared with standard-DHA (mean+/-SD, high-DHA 6.8+/-1.2, standard-DHA 5.2+/-0.7, p<0.0005) but AA was lower (high-DHA 14.9+/-1.3, standard-DHA 16.0+/-1.2, p<0.0005). Feeding preterm infants human milk and formula with 1% DHA raises but does not saturate erythrocyte phospholipids with DHA. Milk exceeding 1% DHA may be required to increase DHA status to levels seen in term infants. 相似文献
7.
The question of whether a dietary supply of docosahexaenoic acid (DHA) and arachidonic acid (ARA) imparts advantages to visual or cognitive development in term infants has been debated for many years. DHA and ARA are present in human milk, and nursing infants consume these fatty acids needed for rapid synthesis of cell membranes, particularly neural cells. The reported mean DHA and ARA levels of human milk worldwide are 0.32% and 0.47% of total fatty acids, respectively. Prior to 2002 in the US, formula-fed infants did not receive these fatty acids and relied solely on endogenous conversion of the dietary essential omega-3 (n-3) and omega-6 (n-6) fatty acids, α-linolenic and linoleic acids, to DHA and ARA, respectively. Formula-fed infants were found to have significantly less accretion of DHA in brain cortex after death than breastfed infants. Numerous studies have found positive correlations between blood DHA levels and improvements in cognitive or visual function outcomes of breastfed and formula-fed infants. Results of randomized controlled clinical trials of term formula-fed infants evaluating functional benefits of dietary DHA and ARA have been mixed, likely due to study design heterogeneity. A comparison of visual and cognitive outcomes in these trials suggests that dietary DHA level is particularly relevant. Trials with formulas providing close to the worldwide human milk mean of 0.32% DHA were more likely to yield functional benefits attributable to DHA. We agree with several expert groups in recommending that infants receive at least 0.3% DHA, with at least 0.3% ARA, in infant feedings; in addition, some clinical evidence suggests that an ARA:DHA ratio greater than 1:1 is associated with improved cognitive outcomes. 相似文献
8.
BackgroundDocosahexaenoic acid (DHA) is an essential fatty acid required for proper growth and development. DHA levels in breast milk vary worldwide. Higher levels are observed among coastal populations and are associated with marine food consumption. Latvia is located in Northern Europe, on the eastern shore of the Baltic Sea. Nevertheless, fish consumption among women of reproductive age is low. The aim of this study was to determine DHA levels in breast milk among lactating women in Latvia.MethodsInvitation to participate in the study was posted on a social media member group for breastfeeding mothers. In total, 71 women were enrolled from November 2016 until December 2017. DHA levels (% of total fatty acids) in breast milk were measured by gas chromatography. Information about food consumed during the three consecutive days prior to the milk sampling was obtained and a food frequency questionnaire (FFQ) was completed. Information about maternal and infant characteristics, current breastfeeding pattern and milk expression method was also collected.ResultsThe mean age of participants was 31?±?4 years and the mean BMI was 22.1?±?3.2. 27 participants were primiparas. The average age and birth weight for infants (34 males, 33 females) was 6?±?4 months and 3.46?±?0.55 kg, respectively. The median DHA level in breast milk (n?=?60) was 0.30?±?0.18% of total fatty acids and it was not influenced by any of the maternal or infant’s characteristics nor current breastfeeding pattern or milk expression manner (p?>?0.05). Fish intake was a positive predictor for DHA levels in breast milk (r?=?0.318, p?=?0.013). Average maternal DHA intake was 136?±?26, 137?±?33 and 178?±?49 (SEM – standard error of the mean) mg, for the third, second and last day prior to sampling day, respectively.ConclusionsDHA levels in breast milk among lactating women in Latvia correspond to the suggested target DHA value in breast milk (0.30%). Fish consumption is a significant positive predictor for DHA levels in breast milk, however, daily DHA intake among the participants was lower than recommended (200 mg). 相似文献
9.
The Dietary Reference Intakes (DRIs) were established to be an indicator of adequacy of dietary nutrients as well as providing levels for adequacy in reducing risk of chronic diseases such as neurodegenerative diseases, cardiovascular diseases, cancers, diabetes mellitus, etc. One particular nutrient that is increasingly discussed as a potential candidate for the generation of a DRI is the omega-3 (n-3) fatty acid docosahexaenoic acid (DHA) due to its potential benefits in reducing risk for cardiovascular disease, role in resolution of inflammation, its importance in cognitive function in infants and inhibiting the progression of neurodegenerative diseases in the elderly. Each reference value refers to and is predicated on estimates of daily nutrient intake and the goal of this paper is to review these intakes. The confidence of these values is critical in establishing dose–response relationships. This paper reports intake values for DHA and examines how these data were generated and the relative confidence in these values. The adult US population is estimated to consume 80–100 mg/d of DHA based on a nationally representative sample of >8400 individuals as part of the National Health and Nutrition Examination Survey (NHANES). This value and those presented for women and men at various ages appear reasonable and should be used as the basis for establishing an Adequate Intake (AI) for DHA. 相似文献
10.
Docosahexaenoic acid (DHA) is an important component of membrane phospholipids in the retina and brain and accumulates rapidly in these tissues during early infancy. DHA is present in human milk, but the amount varies considerably and is largely dependent on maternal diet. This article reviews data addressing the impact of different DHA intakes by lactating women on infant and maternal outcomes to determine if available data are sufficient to estimate optimal breast milk DHA content and estimate dietary reference intakes (DRIs) for DHA by breast-feeding mothers. Results of published observational studies and interventional trials assessing the impact of maternal DHA intake (or breast milk DHA content) on infant visual function, neurodevelopment, and immunologic status were reviewed. Studies related to the potential impact of DHA intake on depression or cognitive function of lactating women also were reviewed. Although only a limited number of studies are available in the current medical literature, and study results have not been consistent, better infant neurodevelopment and/or visual function have been reported with higher vs. lower levels of breast milk DHA. The effect of DHA intake on the incidence or severity of depression in lactating women is not clear. Increasing breast milk DHA content above that typically found in the US, by increasing maternal DHA intake, may confer neurodevelopmental benefits to the recipient breast-fed infant. However, current data are insufficient to permit determination of specific DRIs during this period. 相似文献
11.
Honey is a natural product made by honey bees from the nectar of flowers or secretions produced by other living plant parts. The metal content of the honeys is related to the levels of metals in the environment. Due to the importance of honey in the human diet and the increase of environmental pollution, it is necessary to determine the content of metals in honey to evaluate the toxicological risk derived from its consumption. The objective of this study was to determine the content of 20 metals (Al, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Sr, V, and Zn) in different samples of artisanal honey from the Canary Islands (Spain) in order to evaluate the dietary intake derived from the consumption of these honeys. A total of 161 samples of different types of Canary honey were analyzed by ICP-OES (inductively coupled plasma–optical emission spectrometry). K (825 mg/kg) was the macroelement found in highest concentration, while B (4.25 mg/kg) was the trace element with the highest mean concentration. Al (3.33 mg/kg) was the most abundant toxic metal, followed by Pb (0.040 mg/kg) and Cd (0.002 mg/kg). A mean consumption of 25 g/day of honey mainly contributes to the recommended daily intake of Cu (1.34% adults) and K (0.67% adults). As regards the toxic metals, the contribution percentage to the TDI (tolerable daily intake) of Pb at 2.92% for adults is noteworthy. However, the consumption of honey does not imply a high intake of metals and, therefore, does pose a risk to the health of adult men and women. 相似文献
12.
This study determined impacts of a commercial blend of microencapsulated essential oils (EO), fed at increasing dose levels to high yielding primiparous dairy cows, on milk yield and composition. Eight pregnant Holstein heifers, selected to have their parturition within a period of 30 d, were kept in tie stalls equipped for individual feeding, and with free access to water, from the 7th month of gestation. At an average of 40 d postpartum, cows were assigned to one of four dietary EO levels in a replicated 4 × 4 Latin square design. The experimental diets (i.e., corn silage, fescue hay and a compound feed, 6.5, 4.4 and 8.7 kg DM/d respectively) differed only in the addition level of a microencapsulated EO supplement (RumaXol Feed) mixed at different levels into the compound feed (fed at 1 kg/cow day) in order to provide 0, 0.32, 0.64 and 0.96 g/d of the EO mixture. The experiment had four experimental periods of 21 d, with the last 5 d used for collection of faeces and urine, for milk yield and composition recording and measurement of cow biometric data. The dietary EO supplementation had no effect on dry matter (DM) intake, water consumptions or faecal DM, while urine density was ( P=0.01) lower at the intermediate EO dosages. Digestibility and biometric measures of cows were not modified by EO feeding. The protein content of milk tended ( P=0.06) to be higher at the intermediate EO dosages, as did ( P=0.05) the milk energy concentration. However milk and milk component yields were not affected by EO feeding level. 相似文献
13.
Previous studies suggested that women synthesise docosahexaenoic acid (DHA) more efficiently from their precursors than men. This study investigated the relationship between diet, platelet phospholipids fatty acids and gender. Dietary intake and platelet phosphatidyl-choline (PC) and phosphatidylethanolamine (PE) fatty acids were determined in Caucasian 40 men and 34 women. Absolute and %energy intakes of arachidonic acid (AA), eicosapentaenoic acid (EPA), and DHA, and the ratios of total n-6/n-3 PUFA and linoleic/alpha-linolenic acids did not differ between the sexes. However, women had higher DHA in PC (1.19 vs 1.05 wt%, p<0.05) and PE (3.62 vs 3.21 wt%, p<0.05) than men. Also EPA (1.10 vs 0.93 wt%, p<0.05) was higher in women's PE. Conversely, men had elevated AA and total n-6 fatty acids in PC. The higher platelet DHA levels and lower platelet AA/EPA and AA/DHA ratios in women of child-bearing age compared with men, may lead to less platelet aggregation and vaso-occlusion. 相似文献
14.
Major recurrent affective disorders, including major depressive disorder (MDD) and bipolar disorder, represent a growing public health crisis in the United States. Evidence from cross-national and cross-sectional epidemiological surveys, comparative peripheral and central composition studies, and placebo-controlled intervention trials suggest that n-3 fatty acid deficiency may contribute to the pathoaetiology of affective disorders. These data are reviewed with the objective of estimating a daily docosahexaenoic acid (DHA, 22:6n-3) intake value that is projected to be efficacious in mitigating vulnerability. It is proposed that daily DHA intake sufficient to increase erythrocyte DHA composition to a level found in healthy subjects from Japan (7%), where the lifetime prevalence rates of MDD and bipolar disorder are several fold lower than the US, represents an appropriate target. To achieve this target, preliminary DHA intervention trials indicate that a daily dose of 400–700 mg/d in children and 700–1000 mg/d in adults would be required. Based on the results of placebo-controlled intervention trials, a higher daily DHA dose in the order of 1000–1500 mg/d in a 2:1 eicosapentaenoic acid (EPA, 20:5n-3):DHA ratio may be optimal for the treatment of established affective disorders. These recommendations are intended to guide future dose-ranging placebo-controlled DHA intervention trials in patients with established affective disorders, as well as in asymptomatic subjects at elevated risk for developing affective disorders. Such early intervention studies are currently feasible and will ultimately be required to definitively evaluate whether DHA is a required nutrient for the prevention of affective disorders. 相似文献
15.
ObjectiveIodine is an essential micro nutrient, and a deficiency or excessive intake of this mineral is related to changes in thyroid function. In Brazil, both deficiency and excessive intake of iodine are common; however, excessive intakes have recently been observed. Thus, the objective of the present study was to assess the iodine concentration in maternal milk, taking into account the salt iodine concentration of the participating households and in the infants’ urine. MethodUrine samples from 33 infants (less than 6 months of age), maternal milk samples and samples of the kitchen salt used by the mothers were collected. The iodine levels in the urine and maternal milk were assessed by ICP-MS; the iodine levels in the salt were assessed by titration. ResultThe median iodinuria value in the infants was 293 μg/L; the mean iodine concentration was 206 μg/L in the maternal milk and 39.9 mg I/kg in the salt. There was a positive correlation between the iodine concentration in the maternal milk and the infant iodinuria value. ConclusionThe median infant iodinuria was elevated due to the high iodine concentration present in the maternal milk. High iodine values were caused by high salt iodine levels, which should be reduced. 相似文献
16.
The plasma amino-acid levels in infants of low birth weight fed on expressed human milk and on a proprietary breast-milk substitute, S26, with a protein intake of not more than 4·5 g/kg/day were compared with those in infants fed on an evaporated milk formula whose protein intake ranged from 6·15 to 12·3 g/kg/day, as well as with normal infants on normal feeds and protein intake. In general, there was little difference between the levels in infants of low birth weight and in normal infants on the same protein intake. The five infants of low birth weight on high protein intake had generally higher levels of plasma amino-acids compared with the group on the lower protein intake, and in particular the levels of tyrosine, phenylalanine, methionine, and cystathionine could be extremely high. Apart from methionine these high levels may be the result both of a reduction in activity of the enzymes involved in the metabolism of these amino-acids, due to the immaturity of the infant, and of the increased stress of a high protein intake. In view of a possible long-term effect of abnormally high plasma amino-acid levels it is suggested that the protein intake of infants of low birth weight should not exceed 6 g/kg/day. 相似文献
17.
Thraustochytrids, the heterotrophic, marine, straminipilan protists, are now established candidates for commercial production
of the omega-3 polyunsaturated fatty acid (ω-3 PUFA), docosahexaenoic acid (DHA), that is important in human health and aquaculture.
Extensive screening of cultures from a variety of habitats has yielded strains that produce at least 50% of their biomass
as lipids, and DHA comprising at least 25% of the total fatty acids, with a yield of at least 5 g L −1. Most of the lipids occur as triacylglycerols and a lesser amount as phospholipids. Numerous studies have been carried out
on salinity, pH, temperature, and media optimization for DHA production. Commercial production is based on a fed batch method,
using high C/N ratio that favors lipid accumulation. Schizochytrium DHA is now commercially available as nutritional supplements for adults and as feeds to enhance DHA levels in larvae of aquaculture
animals. Thraustochytrids are emerging as a potential source of other PUFAs such as arachidonic acid and oils with a suite
of PUFA profiles that can have specific uses. They are potential sources of asataxanthin and carotenoid pigments, as well
as other lipids. Genes of the conventional fatty acid synthesis and the polyketide-like PUFA synthesis pathways of thraustochytrids
are attracting attention for production of recombinant PUFA-containing plant oils. Future studies on the basic biology of
these organisms, including biodiversity, environmental adaptations, and genome research are likely to point out directions
for biotechnology explorations. Potential areas include enzymes, polysaccharides, and secondary metabolites. 相似文献
19.
The German, Austrian and Swiss nutrition societies are the joint editors of the ‘reference values for nutrient intake’. They have revised the reference values for the intake of selenium and published them in February 2015. The saturation of selenoprotein P (SePP) in plasma is used as a criterion for the derivation of reference values for selenium intake in adults. For persons from selenium-deficient regions (China) SePP saturation was achieved with a daily intake of 49 μg of selenium. When using the reference body weights the D-A-CH reference values are based upon, the resulting estimated value for selenium intake is 70 μg/day for men and 60 μg/day for women. The estimated value for selenium intake for children and adolescents is extrapolated using the estimated value for adults in relation to body weight. For infants aged 0 to under 4 months the estimated value of 10 μg/day was derived from the basis of selenium intake via breast milk. For infants aged 4 to under 12 months this estimated value was used and taking into account the differences regarding body weight an estimated value of 15 μg/day was derived. For lactating women compared to non-lactating women a higher reference value of 75 μg/day is indicated due to the release of selenium with breast milk. The additional selenium requirement for pregnant women is negligible, so that no increased reference value is indicated. 相似文献
20.
Although laboratory studies suggest that long-chain n-3 polyunsaturated fatty acids (LCn3PUFAs) may reduce risk of asthma, epidemiological data remain controversial and inconclusive. We quantitatively reviewed the epidemiological studies published through December 2012 in PubMed and EMBASE by using a fixed-effects or random-effects model. Eleven studies, comprised of 99,093 individuals (3,226 cases), were included in the final dataset. Of them, 7 studies examined associations between intake of fish or LCn3PUFA and risk of asthma: 4 studies in children (996 cases from 12,481 children) and 3 in adults (1,311 cases from 82,553 individuals). Two studies (69 cases from 276 infants) investigated LCn3PUFA levels in mothers’ milk, and two studies assessed maternal fish consumption (786 cases from 2,832 individuals) during lactation and/or plasma LCn3PUFA levels during pregnancy (64 cases from 951 infants) in relation to offspring’s asthma. The pooled relative risk of child asthma were 0.76 (95% CI, 0.61–0.94) for fish consumption and 0.71 (95% CI, 0.52–0.96) for LCn3PUFA intake. No statistically significant association was found in studies among adults. Epidemiological data to date indicate that fish or LCn3PUFA intake may be beneficial to prevent asthma in children. Further studies are needed to establish causal inference and to elucidate the potential mechanisms. 相似文献
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