Dietary Lipid Intake Influences the Alpha-tocopherol Levels in Human Milk.

OBJECTIVE: Dietary lipid intake is associated with serum alpha-tocopherol levels; however, its impact on human milk is unknown. The objective of this study was to evaluate the relationship between maternal intake of vitamin E, lipids, and fatty acids and the concentration of alpha-tocopherol in human milk. METHODS: We conducted a longitudinal observational study, including 143 lactating women on 7, 30, and 90 days postpartum. Dietary intake was collected using 24-hour recall. On day 90, a human milk sample was collected and analyzed for alpha-tocopherol concentration. The prevalence of inadequate vitamin E intake was determined by the Estimated Average Requirement (16 mg/day), and the alpha-tocopherol concentration was analyzed by high-performance liquid chromatography. RESULTS: Dietary intake of vitamin E was associated with the intake of lipids (r = 0.237, P = 0.004) and fatty acids (P < 0.05), and 100% of the participants had inadequate vitamin intake. Mean alpha-tocopherol concentration in the human milk samples was 7.11 (standard deviation 3.95) µmol/L and was correlated with lipid (r = 0.201, P = 0.042) and polyunsaturated fatty acid intake (r = 0.235, P = 0.017). Higher vitamin E levels were found in participants with the highest quartile of polyunsaturated fatty acid intake. CONCLUSIONS: Alpha-tocopherol concentration was associated with the dietary intake of lipids and fatty acids, demonstrating that its bioavailability is associated with fats in the mammary gland. These results suggest development of appropriate strategies to increase the levels of vitamin E in breast milk that may help to prevent and treat vitamin E deficiency.

Vitamin E concentration in human milk and associated factors: a literature review, / Concentração de vitamina E no leite humano e fatores associados: uma revisão de literatura,

Objective: To systematize information about vitamin E concentration in human milk and the variables associated with this composition in order to find possible causes of deficiency, supporting strategies to prevent it in postpartum women and infants. Source: Studies published between 2004 and 2014 that assayed alpha-tocopherol in human milk of healthy women by high performance liquid chromatography were evaluated. The keywords used were "vitamin E", "alpha-tocopherol", "milk, human", "lactation", and equivalents in Portuguese, in the BIREME, CAPES, PubMed, SciELO, ISI Web of Knowledge, HighWire Press, Ingenta, and Brazilian Digital Library of Theses and Dissertations databases. Summary of the findings: Of the 41 publications found on the subject, 25 whose full text was available and met the inclusion criteria were selected. The alpha-tocopherol concentrations found in milk were similar in most populations studied. The variable phase of lactation was shown to influence vitamin E content in milk, which is reduced until the mature milk appears. Maternal variables parity, anthropometric nutritional status, socioeconomic status, and habitual dietary intake did not appear to affect the alpha-tocopherol levels in milk. However, the influence of the variables maternal age, gestational age, biochemical nutritional status in alpha-tocopherol, and maternal supplementation with vitamin E had conflicting results in the literature. Conclusion: Alpha-tocopherol concentration in milk decreases during lactation, until the mature milk appears. To confirm the influence of some maternal and child variables on milk vitamin E content, further studies with adequate design are needed. .

Objetivo: Sistematizar informações sobre a concentração de vitamina E no leite humano e variáveis associadas a essa composição, a fim de encontrar possíveis causas de deficiência, subsidiando estratégias para prevenção desta em puérperas e lactentes. Fonte dos dados: Foram avaliados estudos publicados entre 2004 e 2014 que determinaram o alfa-tocoferol no leite humano de mulheres saudáveis por Cromatografia Líquida de Alta Eficiência. Os descritores utilizados foram "leite humano", "alfa-tocoferol", "vitamina E", "lactação" e seus equivalentes em inglês, nas bases de dados BIREME, Periódicos CAPES, Pub-Med, SciELO, ISI Web of Knowledge, HighWire Press, Ingenta e Biblioteca Digital Brasileira de Teses e Dissertações. Síntese dos dados: Das 41 publicações encontradas sobre a temática, 25 foram selecionadas, por possuirem texto completo disponível e se encaixarem nos critérios de inclusão. As concentrações encontradas de alfa-tocoferol no leite foram semelhantes na maioria das populações estudadas. A variável fase de lactação mostrou influenciar o conteúdo dessa vitamina no leite, que vai sendo reduzido até o leite maduro. As variáveis maternas paridade, estado nutricional antropométrico, condição socioeconômica e ingestão dietética habitual parecem não afetar os níveis de alfa-tocoferol no leite. Entretanto, a influência das variáveis idade materna, idade gestacional, estado nutricional bioquímico em alfa-tocoferol e suplementação materna com vitamina E possui resultados conflitantes na literatura. Conclusão: A concentração de alfa-tocoferol no leite diminui durante a lactação, até chegar ao leite maduro. Para confirmar a influência de algumas ...

Vitamin E concentration in human milk and associated factors: a literature review.

OBJECTIVE: To systematize information about vitamin E concentration in human milk and the variables associated with this composition in order to find possible causes of deficiency, supporting strategies to prevent it in postpartum women and infants. SOURCE: Studies published between 2004 and 2014 that assayed alpha-tocopherol in human milk of healthy women by high performance liquid chromatography were evaluated. The keywords used were "vitamin E", "alpha-tocopherol", "milk, human", "lactation", and equivalents in Portuguese, in the BIREME, CAPES, PubMed, SciELO, ISI Web of Knowledge, HighWire Press, Ingenta, and Brazilian Digital Library of Theses and Dissertations databases. SUMMARY OF THE FINDINGS: Of the 41 publications found on the subject, 25 whose full text was available and met the inclusion criteria were selected. The alpha-tocopherol concentrations found in milk were similar in most populations studied. The variable phase of lactation was shown to influence vitamin E content in milk, which is reduced until the mature milk appears. Maternal variables parity, anthropometric nutritional status, socioeconomic status, and habitual dietary intake did not appear to affect the alpha-tocopherol levels in milk. However, the influence of the variables maternal age, gestational age, biochemical nutritional status in alpha-tocopherol, and maternal supplementation with vitamin E had conflicting results in the literature. CONCLUSION: Alpha-tocopherol concentration in milk decreases during lactation, until the mature milk appears. To confirm the influence of some maternal and child variables on milk vitamin E content, further studies with adequate design are needed.

Avaliação dos níveis de retinol no colostro humano coletado no intervalo de 24 horas / Evaluation of retinol levels in human colostrum in two samples collected at an interval of 24 hours

OBJETIVO: Avaliar a concentração de retinol no colostro coletado em intervalo de 24 h. MÉTODOS: Coletou-se o colostro de 24 puérperas em dois períodos, tempo zero (T0) e tempo 24 h (T24), e um pool da união de T0 e T24. A gordura foi determinada pelo crematócrito, e o retinol por cromatografia líquida de alta eficiência. RESULTADOS: Quando expresso por volume de leite (μg/dL), o nível de retinol sofreu variações entre T0, T24 e pool: 94,9±58,9; 129±78,6 e 111,9±60,4 μg/dL, respectivamente. Entretanto, quando expresso pela quantidade de gordura (μg/g), não foi observada diferença significativa. CONCLUSÕES: O retinol quantificado no colostro através de coleta única não deve ser utilizado como indicador do estado nutricional em vitamina A, devido à grande variabilidade no decorrer das coletas. Sugere-se que os resultados sejam expressos por grama de gordura, para minimizar as variações em decorrência do volume de leite.

OBJECTIVE: To evaluate retinol concentration in colostrum samples collected with a 24 hour interval. METHODS: Colostrum was collected from 24 recently-delivered mothers at two points in time, 0 hours (T0) and 24 hours later (T24), and a pooled sample of colostrum from T0 and T24 was also analyzed. Fat content was determined by creamatocrit, and retinol assayed by high performance liquid chromatography. RESULTS: When expressed in terms of volume of milk (µg/dL), retinol levels varied across T0, T24 and the pooled sample: 94.9±58.9, 129±78.6 and 111.9±60.4 µg/dL, respectively. However, when expressed with relation to fat content (µg/g), no significant difference was observed. CONCLUSIONS: Retinol assayed in colostrum from a single sample should not be used as an indicator of vitamin A nutritional status, due to the great variation between samples collected at different times. It is suggested that results be expressed per gram of fat, in order to minimize variations resulting from the volume of milk.

Evaluation of retinol levels in human colostrum in two samples collected at an interval of 24 hours.

OBJECTIVE: To evaluate retinol concentration in colostrum samples collected with a 24 hour interval. METHOD: Colostrum was collected from 24 recently-delivered mothers at two points in time, 0 hours (T0) and 24 hours later (T24), and a pooled sample of colostrum from T0 and T24 was also analyzed. Fat content was determined by creamatocrit, and retinol assayed by high performance liquid chromatography. RESULTS: When expressed in terms of volume of milk (microg/dL), retinol levels varied across T0, T24 and the pooled sample: 94.9+/-58.9; 129+/-78.6 and 111.9+/-60.4 microg/dL, respectively. However, when expressed with relation to fat content (microg/g), no significant difference was observed. CONCLUSIONS: Retinol assayed in colostrum from a single sample should not be used as an indicator of vitamin A nutritional status, due to the great variation between samples collected at different times. It is suggested that results be expressed per gram of fat, in order to minimize variations resulting from the volume of milk.

[The effect of processing on the Vitamin A content of human milk]. / Efeito do processamento do leite humano sobre os níveis de retinol.

OBJECTIVES: To analyze the effect of processing on the Vitamin A levels of milk that is donated to the Human Milk Bank at the University Maternity Hospital, and to evaluate whether this milk supplies the infants' Vitamin A requirement. METHODS: Sixty milk samples from the Human Milk Bank were divided into two equal portions. One milk portion was extracted prior to processing, while another fraction was subjected to pasteurization and later extracted. The samples were analyzed using high performance liquid chromatography. Analysis with Student's t test indicated that the difference between mean retinol levels was statistically significant at the p < 0.05 level. RESULTS: The retinol content found in the milk prior to processing was 55.4+/-34.0 microg/100 ml, whereas for the processed milk this level was 36.6+/-26.1 microg/100 ml (p < 0.001). CONCLUSION: It was found that retinol loss occurs during milk processing and that the milk from the Human Milk Bank does not meet infants' Vitamin A requirement.

Efeito do processamento do leite humano sobre os níveis de retinol / The effect of processing on the Vitamin A content of human milk

OBJETIVOS: Analisar o efeito do processamento sobre os níveis de retinol no leite humano ordenhado, bem como avaliar se o mesmo supre o requerimento nutricional de vitamina A do lactente. MÉTODOS: Foram coletadas 60 amostras de leite humano ordenhado no Banco de Leite Humano da Maternidade Escola Januário Cicco e divididas em duas alíquotas de 5 ml cada, sendo uma não processada termicamente, enquanto a outra foi submetida à pasteurização. As amostras foram analisadas por cromatografia líquida de alta eficiência. Para a análise estatística, foi utilizado o teste t de Student, sendo a diferença entre as médias considerada significativa quando p < 0,05. RESULTADOS: A concentração de retinol encontrado no leite antes da pasteurização foi de 55,4±34,0 µg/100 ml, enquanto que a presente no leite processado foi de 36,6±26,1 µg/100 ml (p < 0,001). Considerando um consumo de 500 ml de leite por dia, observou-se que o leite anterior à pasteurização ofereceu 69,3 por cento das necessidades diárias recomendadas, e o leite processado, 45,8 por cento. CONCLUSÃO: Os níveis de retinol são mais baixos no leite processado termicamente e, nessa concentração, não atingem o requerimento de vitamina A do lactente.

[Retinol levels in human colostrum: influence of child, maternal and socioeconomic variables]. / Influência de variáveis socioeconômicas e de saúde materno-infantil sobre os níveis de retinol no colostro humano.

OBJECTIVES: To determine colostrum retinol levels in breastfeeding women from the city of Natal, state of Rio Grande do Norte, Brazil, and to investigate the relationship between retinol levels in colostrum and child, maternal and socioeconomic variables. METHODS: Forty-two healthy women aged 18 to 39 years were evaluated 48 hours after delivery. Socioeconomic, anthropometric, and dietary data were collected by means of a questionnaire. Body mass index was used to determine nutritional status. The Virtual Nutri software was used to analyze data on daily intake of vitamin A. Retinol levels were determined in 2 ml of colostrum using high-performance liquid chromatography. RESULTS: Most women were of low socioeconomic and educational backgrounds. Vitamin A intake was adequate in 55% of the women (mean intake = 1,398.8 micro g RE/day). The mean amount of retinol in colostrum was 93.1 51.1 micro gRE/100 ml. No significant differences were found in terms of milk retinol levels for the variables income (p = 0.503), educational level (p = 0.708) and birth weight (p = 0. 499). However, a statistically significant difference was observed for nutritional status during pregnancy (0.016). CONCLUSION: The lack of influence of socioeconomic factors on colostrum retinol levels suggests the existence of an adaptive mechanism of the mammary gland to maintain adequate retinol levels that meet the infantacute;s daily needs.

Influência de variáveis socioeconômicas e de saúde materno-infantil sobre os níveis de retinol no colostro humano / Retinol levels in human colostrum: influence of child, maternal and socioeconomic variables

OBJETIVO: Determinar os níveis de retinol no colostro de lactantes moradoras da cidade de Natal (RN) e sua relaçäo com as variáveis socioeconômicas e de saúde materno-infantil. MÉTODOS: Foram avaliadas 42 nutrizes saudáveis, entre 18 e 39 anos, até 48 horas pós-parto. Foram aplicados questionários para a coleta de dados socioeconômicos, antropométricos e dietéticos. O estado nutricional antropométrico foi determinado pelo índice de massa corpórea e os dados de consumo alimentar em vitamina A foram obtidos pelo inquérito dietético de história alimentar, sendo a análise realizada pelo programa Virtual Nutri. Foram coletados 2 ml de colostro, e a determinaçäo do retinol foi realizada por cromatografia líquida de alta eficiência. RESULTADOS: A maioria das nutrizes apresentou baixa condiçäo socioeconômica e baixo grau de escolaridade. Entre as nutrizes, 55 por cento apresentavam um consumo de vitamina A adequado, com uma média de ingestäo de 1.398,8 ægRE/dia. O valor médio de retinol no colostro foi 93,1+51,1 ægRE/100 ml. Quando relacionado aos níveis de retinol no leite, as variáveis renda (p = 0,503), escolaridade (p = 0,708) e peso ao nascer do bebê (p = 0,499) näo apresentaram diferenças significativas. Entretanto, houve diferença estatisticamente significativa entre o nível de retinol no leite e o estado nutricional na gestaçäo (p = 0,016). CONCLUSÄO: A näo-influência de variações socioeconômicas nos níveis de retinol do colostro sugere a existência de um mecanismo de adaptaçäo da glândula mamária na manutençäo dos níveis adequados de retinol para atender às necessidades diárias do lactente