VITAMIN E IN HUMAN MILK AND ITS RELATION TO THE NUTRITIONAL REQUIREMENT OF THE TERM NEWBORN. / VITAMINA E NO LEITE HUMANO E SUA RELAÇÃO COM O REQUERIMENTO NUTRICIONAL DO RECÉM-NASCIDO A TERMO.

OBJECTIVES: To determine the alpha-tocopherol concentration in breast milk at different periods of lactation and to estimate the possible supply of vitamin E to the infant. METHODS: A longitudinal observational study was carried out with 100 mothers at University Hospital Ana Bezerra (HUAB), at Universidade Federal do Rio Grande do Norte, in Santa Cruz (RN), Northeast Brazil. Samples of colostrum (n=100), transitional milk (n=77), and mature milk (n=63) were collected. Alpha-tocopherol was analyzed by high-performance liquid chromatography. Vitamin supply to the newborn was estimated by comparing the nutritional requirement of vitamin E (4 mg/day) with the potential daily intake of milk. RESULTS: The mean alpha-tocopherol concentration found in colostrum, transitional, and mature milk was 40.5±15.0 µmol/L, 13.9±5.2 µmol/L, and 8.0±3.8 µmol/L, respectively (p<0.001). The possible effect of these milks offered to the infant 6.2 mg/day of vitamin E in colostrum, 4.7 mg/day in transitional milk, and 2.7 mg/day in mature milk (p<0.0001), shows that only the mature milk did not guarantee the recommended quantity of this vitamin. CONCLUSIONS: Alpha-tocopherol levels in human milk decrease through the progression of lactation, and the possible intake of colostrum and transitional milk met the nutritional requirement of the infant. Mature milk may provide smaller amounts of vitamin E. Thus, it is important to study the factors that are associated with such low levels.

OBJETIVOS: Determinar a concentração de alfa-tocoferol no leite materno em diferentes períodos de lactação e estimar o provável fornecimento de vitamina E ao lactente. MÉTODOS: Estudo longitudinal observacional realizado com 100 puérperas atendidas para o parto no Hospital Universitário Ana Bezerra (HUAB) da Universidade Federal do Rio Grande do Norte (UFRN), em Santa Cruz (RN). Foram coletados leite colostro (n=100), leite de transição (n=77) e leite maduro (n=63) no seguimento da lactação. O alfa-tocoferol foi analisado por cromatografia líquida de alta eficiência. O fornecimento de vitamina E para o neonato foi estimado comparando-se o requerimento nutricional de vitamina E (4 mg/dia) com a ingestão diária de leite. RESULTADOS: A concentração média de alfa-tocoferol encontrada nos leites colostro, de transição e maduro foi 40,5±15,0 µmol/L, 13,9±5,2 µmol/L e 8,0±3,8 µmol/L, respectivamente (p<0,001). A possível ingestão desses leites pelo lactente forneceu 6,2 mg/dia de vitamina E no colostro, 4,7 mg/dia no de transição e 2,7 mg/dia no maduro (p<0,0001), evidenciando que apenas o último não garantiu a quantidade recomendada dessa vitamina. CONCLUSÕES: Os níveis de alfa-tocoferol no leite diminuíram com a progressão da lactação, e a provável ingestão dos leites colostro e de transição conseguiu atender ao requerimento nutricional do lactente. O leite maduro pode fornecer menores quantidades da vitamina E, o que torna importante o estudo dos fatores que se associam a esses baixos níveis.

Vitamina e no leite humano e sua relação com o requerimento nutricional do recém-nascido a termo / Vitamin e in human milk and its relation to the nutritional requirement of the term newborn

RESUMO Objetivos: Determinar a concentração de alfa-tocoferol no leite materno em diferentes períodos de lactação e estimar o provável fornecimento de vitamina E ao lactente. Métodos: Estudo longitudinal observacional realizado com 100 puérperas atendidas para o parto no Hospital Universitário Ana Bezerra (HUAB) da Universidade Federal do Rio Grande do Norte (UFRN), em Santa Cruz (RN). Foram coletados leite colostro (n=100), leite de transição (n=77) e leite maduro (n=63) no seguimento da lactação. O alfa-tocoferol foi analisado por cromatografia líquida de alta eficiência. O fornecimento de vitamina E para o neonato foi estimado comparando-se o requerimento nutricional de vitamina E (4 mg/dia) com a ingestão diária de leite. Resultados: A concentração média de alfa-tocoferol encontrada nos leites colostro, de transição e maduro foi 40,5±15,0 µmol/L, 13,9±5,2 µmol/L e 8,0±3,8 µmol/L, respectivamente (p<0,001). A possível ingestão desses leites pelo lactente forneceu 6,2 mg/dia de vitamina E no colostro, 4,7 mg/dia no de transição e 2,7 mg/dia no maduro (p<0,0001), evidenciando que apenas o último não garantiu a quantidade recomendada dessa vitamina. Conclusões: Os níveis de alfa-tocoferol no leite diminuíram com a progressão da lactação, e a provável ingestão dos leites colostro e de transição conseguiu atender ao requerimento nutricional do lactente. O leite maduro pode fornecer menores quantidades da vitamina E, o que torna importante o estudo dos fatores que se associam a esses baixos níveis.

ABSTRACT Objectives: To determine the alpha-tocopherol concentration in breast milk at different periods of lactation and to estimate the possible supply of vitamin E to the infant. Methods: A longitudinal observational study was carried out with 100 mothers at University Hospital Ana Bezerra (HUAB), at Universidade Federal do Rio Grande do Norte, in Santa Cruz (RN), Northeast Brazil. Samples of colostrum (n=100), transitional milk (n=77), and mature milk (n=63) were collected. Alpha-tocopherol was analyzed by high-performance liquid chromatography. Vitamin supply to the newborn was estimated by comparing the nutritional requirement of vitamin E (4 mg/day) with the potential daily intake of milk. Results: The mean alpha-tocopherol concentration found in colostrum, transitional, and mature milk was 40.5±15.0 µmol/L, 13.9±5.2 µmol/L, and 8.0±3.8 µmol/L, respectively (p<0.001). The possible effect of these milks offered to the infant 6.2 mg/day of vitamin E in colostrum, 4.7 mg/day in transitional milk, and 2.7 mg/day in mature milk (p<0.0001), shows that only the mature milk did not guarantee the recommended quantity of this vitamin. Conclusions: Alpha-tocopherol levels in human milk decrease through the progression of lactation, and the possible intake of colostrum and transitional milk met the nutritional requirement of the infant. Mature milk may provide smaller amounts of vitamin E. Thus, it is important to study the factors that are associated with such low levels.

Breast milk retinol concentration in mothers of preterm newborns.

BACKGROUND: Preterm newborns have low vitamin A reserves at birth, which increases their risk of morbidity and mortality. In the absence of supplementation, breast milk is the only source of this nutrient for exclusively breastfed infants. AIMS: To assess retinol concentration in preterm milk and the relationship between this retinol concentration and lactation phase, degree of prematurity, and maternal serum retinol level. STUDY DESIGN: Longitudinal study. SUBJECTS: Fifty-eight preterm mothers. OUTCOME MEASURES: Colostrum (1-3d), transitional (7-15d), and mature human milk (30-55d) samples were collected. Maternal blood was collected once at postpartum. Retinol level was measured using high-performance liquid chromatography. RESULTS: Milk retinol concentration was statistically different between lactation phases (p<0.001): 2.84±1.05µmol/L in colostrum (58), 3.47±1.28µmol/L in transitional (58), and 2.03±0.61µmol/L in mature milk (30). No difference was found in milk retinol levels between groups with different degrees of prematurity (p>0.05). Maternal serum retinol (1.82±0.50µmol/L) did not correlate with milk levels (p>0.05). CONCLUSIONS: Retinol level in preterm milk seems to be independent of the degree of prematurity and maternal serum status. A significant increase in micronutrient levels in transitional milk was observed, which is likely to contribute to reserves in the premature liver.

Effect of maternal supplementation with vitamin E on the concentration of α-tocopherol in colostrum / Efeito da suplementação materna com vitamina E sobre a concentração de α-tocopherolol no colostro

Abstract: Objective: To evaluate the effect of maternal supplementation with vitamin E on the concentration of α-tocopherol in colostrum and its supply to the newborn. Method: This randomized clinical trial enrolled 99 healthy adult pregnant women; of these, 39 were assigned to the control group and 60 to the supplemented group. After an overnight fast, 5 mL of blood and 2 mL of colostrum were collected. After the first sampling (0 h milk), the supplemented group received 400 IU of supplementary vitamin E. Another 2 mL milk aliquot was collected in both groups 24 h after supplementation (24 h milk). The samples were analyzed by high-performance liquid chromatography. The α-tocopherol content provided by colostrum was calculated by considering a daily intake of 396 mL of milk and comparing the resulting value to the recommended daily intake for infants aged 0-6 months (4 mg/day). Results: The initial mean concentration of α-tocopherol in colostrum was 1509.3 ± 793.7 µg/dL in the control group and 1452.9 ± 808.6 µg/dL in the supplemented group. After 24 h, the mean α-tocopherol concentration was 1650.6 ± 968.7 µg/dL in the control group (p > 0.05) and 2346.9 ± 1203.2 µg/dL in the supplemented group (p < 0.001), increasing the vitamin E supply to the newborn to 9.3 mg/day. Initially, 18 women in the supplemented group provided colostrum α-tocopherol contents below 4 mg/day; after supplementation only six continued to provide less than the recommended amount. Conclusion: Maternal vitamin E supplementation increases the supply of the vitamin to the infant by providing more than twice the Recommended Daily Intake.

Resumo: Objetivo: Avaliar o efeito da suplementação materna com vitamina E sobre a concentração de α-tocoferol no colostro e o fornecimento dessa para o recém-nascido. Método: O estudo clínico randomizado foi feito com 99 parturientes adultas e saudáveis, 39 alocadas no grupo controle e 60 no grupo suplementado. Após jejum noturno, foram coletados 5 mL de sangue e 2 mL de colostro das parturientes. Após a primeira coleta (leite 0 h), o grupo suplementado recebeu suplementação com 400 UI de vitamina E. Foi feita nova coleta de 2 mL de colostro, em ambos os grupos, 24 h após a suplementação (leite 24 h). As amostras foram analisadas por cromatografia líquida de alta eficiência. A quantidade de α-tocoferol fornecida pelo colostro foi considerada para uma ingestão diária de 396 mL de leite e comparada com a ingestão diária recomendada para crianças de 0 a 6 meses (4 mg/dia). Resultados: A concentração média inicial de α-tocoferol no colostro foi de 1.509,3 ± 793,7 µg/dL no grupo controle e 1.452,9 ± 808,6 µg/dL no grupo suplementado. Após 24 horas a concentração média de α-tocoferol no grupo controle foi de 1.650,6 ± 968,7 µg/dL (p > 0,05) e de 2.346,9 ± 1203,2 µg/dL (p < 0,001) no grupo suplementado. Aumentou-se assim a oferta de vitamina E para o recém-nascido para 9,3 mg/dia. Inicialmente 18 mulheres do grupo suplementado forneciam valores inferiores a 4 mg/dia de α-tocoferol em seu colostro, após suplementação apenas seis continuaram a fornecer quantidade inferior ao recomendado. Conclusão: A suplementação materna com vitamina E promove o aumento do fornecimento da vitamina para o recém-nascido e fornece mais do que o dobro da ingestão diária recomendada.

Effect of maternal supplementation with vitamin E on the concentration of α-tocopherol in colostrum.

OBJECTIVE: To evaluate the effect of maternal supplementation with vitamin E on the concentration of α-tocopherol in colostrum and its supply to the newborn. METHOD: This randomized clinical trial enrolled 99 healthy adult pregnant women; of these, 39 were assigned to the control group and 60 to the supplemented group. After an overnight fast, 5mL of blood and 2mL of colostrum were collected. After the first sampling (0h milk), the supplemented group received 400IU of supplementary vitamin E. Another 2mL milk aliquot was collected in both groups 24h after supplementation (24h milk). The samples were analyzed by high-performance liquid chromatography. The α-tocopherol content provided by colostrum was calculated by considering a daily intake of 396mL of milk and comparing the resulting value to the recommended daily intake for infants aged 0-6 months (4mg/day). RESULTS: The initial mean concentration of α-tocopherol in colostrum was 1509.3±793.7µg/dL in the control group and 1452.9±808.6µg/dL in the supplemented group. After 24h, the mean α-tocopherol concentration was 1650.6±968.7µg/dL in the control group (p>0.05) and 2346.9±1203.2µg/dL in the supplemented group (p<0.001), increasing the vitamin E supply to the newborn to 9.3mg/day. Initially, 18 women in the supplemented group provided colostrum α-tocopherol contents below 4mg/day; after supplementation only six continued to provide less than the recommended amount. CONCLUSION: Maternal vitamin E supplementation increases the supply of the vitamin to the infant by providing more than twice the Recommended Daily Intake.

Influência do tempo de armazenamento sobre a concentração de alfa-tocoferol e gama-tocoferol em óleos vegetais / Influence of the storage time on the concentration of alpha-tocopherol and gamma-tocopherol in vegetable oils

O alfa- e o gama-tocoferol estão entre os homólogos da vitamina E, que possui importante papel como antioxidante. As fontes dietéticas mais ricas em vitamina E são os óleos vegetais. Este trabalho avaliou os níveis de alfa- e gama-tocoferol nos óleos de canola, girassol, milho e soja, e averiguou sua variação com o tempo de armazenamento. Os óleos vegetais foram adquiridos nos supermercados da cidade de Natal/RN, e mantidos sob temperatura ambiente e ao abrigo da luz. As análises foram realizadas em diferentes momentos durante o armazenamento (tempo 0 e após 30, 60 e 90 dias). Cromatografia líquida de alta eficiência (CLAE) foi usada para determinar as concentrações dos analitos. A análise estatística foi realizada utilizando-se o teste de variância (ANOVA) e as diferenças foram consideradas estatisticamente significativas quando p < 0,05. Ao final do tempo de armazenamento (90 dias) foi verificada diminuição significativa nos níveis de alfa- e gama-tocoferolde 38,7 % e 36,0 %, no óleo de canola; 42,2 % e 22,2 %, no óleo de soja; 28,3 % e 29,2 %, no óleo de girassol;39,0 % e 17,9 %, no óleo de milho, respectivamente. As concentrações de alfa- e gama-tocoferol nos óleos vegetais reduziram significativamente após armazenamento, sob as condições empregadas no estudo.

The alpha- and gamma-tocopherol are among the homologues of vitamin E which plays a key role as anantioxidant. The richest dietary sources of vitamin E are vegetable oils. This study aimed at evaluating thealpha- and gamma-tocopherol contents in oils from canola, sunflower, corn and soybeans, and to verify their variations after storage time. The vegetable oils were purchased at supermarkets in Natal / RN, and they were keptat room temperature and protected from light. The tests was made at different times during storage (time 0 and after 30, 60 and 90 days). The high performance liquid chromatography (HPLC) was used to determinetheir concentrations. The statistical analysis was performed using analysis of variance (ANOVA) test and thedifferences were considered statistically significant when p < 0.05. By the end of the storage time (90 days), thealpha- and gamma-tocopherol contents showed a significant decrease of 38.7 % and 36.0 % for canola oil; 42.2 %and 22.2 % in soybean oil; 28.3 % and 29.2 % in sunflower oil; 39.0 % and 17.9 % in corn oil, respectively.The concentrations of alpha- and gamma-tocopherol in vegetable oils significantly decreased after the storageperiod under the conditions used in this study.

Alpha-tocopherol concentration in serum and colostrum of mothers with gestational diabetes mellitus.

OBJECTIVE: To evaluate and compare the levels of α-tocopherol in colostrum and in the serum of healthy and diabetic mothers. METHODS: This cross-sectional study enrolled 51 volunteer mothers, 20 with the diagnosis of gestational diabetes mellitus and 31 without associated diseases. Serum and colostrum samples were collected in fasting in the immediate postpartum period and α-tocopherol was analyzed by high performance liquid chromatography (HPLC). In order to define the nutritional status of vitamin E, the cutoff point for the serum (697.7µg/dL) was adopted. Student's t-test for independent variables compared the average concentrations of α-tocopherol in the serum and in the colostrum between control and gestational diabetes mellitus groups. Pearson's correlation was used to assess the relationship between the concentration of α-tocopherol in serum and colostrum for both groups. Differences were considered significant when p<0.05. RESULTS: The α-tocopherol concentration in colostrum was 1,483.1±533.8µg/dL for Control Group and 1,368.8±681.8µg/dL for diabetic women, without differences between groups (p=0.50). However, α-tocopherol concentration in the serum was 1,059.5±372.7µg/dL in the Control Group and 1,391.4±531.5µg/dL in the diabetic one (p<0.01). No correlation was found between the concentration of α-tocopherol in the serum and in the colostrum for control and diabetic groups. CONCLUSIONS: The groups had adequate nutritional status of vitamin E. Gestational diabetes was not associated with changes in α-tocopherol concentration in colostrum.

Alpha-tocopherol concentration in serum and colostrum of mothers with gestational diabetes mellitus / Concentración de ?-tocoferol en el suero y calostro de madres con diabetes mellitus gestacional / Concentração de ?-tocoferol no soro e colostro de mães com diabetes melito gestacional

To evaluate and compare the levels of α-tocopherol in colostrum and in the serum of healthy and diabetic mothers. METHODS: This cross-sectional study enrolled 51 volunteer mothers, 20 with the diagnosis of gestational diabetes mellitus and 31 without associated diseases. Serum and colostrum samples were collected in fasting in the immediate postpartum period and α-tocopherol was analyzed by high performance liquid chromatography (HPLC). In order to define the nutritional status of vitamin E, the cutoff point for the serum (697.7µg/dL) was adopted. Student's t-test for independent variables compared the average concentrations of α-tocopherol in the serum and in the colostrum between control and gestational diabetes mellitus groups. Pearson's correlation was used to assess the relationship between the concentration of α-tocopherol in serum and colostrum for both groups. Differences were considered significant when p<0.05. RESULTS: The α-tocopherol concentration in colostrum was 1,483.1±533.8µg/dL for Control Group and 1,368.8±681.8µg/dL for diabetic women, without differences between groups (p=0.50). However, α-tocopherol concentration in the serum was 1,059.5±372.7µg/dL in the Control Group and 1,391.4±531.5µg/dL in the diabetic one (p<0.01). No correlation was found between the concentration of α-tocopherol in the serum and in the colostrum for control and diabetic groups. CONCLUSIONS: The groups had adequate nutritional status of vitamin E. Gestational diabetes was not associated with changes in α-tocopherol concentration in colostrum...

Evaluar y comparar la concentración de α-tocoferol en la leche calostro y en el suero de madres diabéticas y sanas. MÉTODOS: Estudio transversal, realizado con 51 parturientes voluntarias, siendo 20 diagnosticadas con diabetes mellitus gestacional y 31 sin cualquier enfermedad asociada. Se recogieron las muestras de suero y de calostro en ayuno en el postparto inmediato y se analizó el α-tocoferol por cromatografía líquida de alta eficiencia (CLAE). Para definir el estado nutricional de vitamina E, se adoptó el punto de corte sérico (697,7µg/dL). El análisis estadístico se realizó con la prueba t de Student para variables independientes a fin de comparar las concentraciones medianas de α-tocoferol en el suero entre los grupos control y con diabetes mellitus gestacional. Ese análisis también fue realizado para comparar los promedios de α-tocoferol en el calostro en los grupos estudiados. Se utilizó la correlación de Pearson para evaluar la relación entre la concentración de α-tocoferol en el suero y en el calostro para ambos grupos. Las diferencias fueron consideradas significativas cuando p<0,05. RESULTADOS: Las concentraciones de α-tocoferol en el calostro fueron 1.483,1±533,8µg/dL para las mujeres del Grupo Control y 1.368,8±681,8µg/dL para las diabéticas, no habiendo diferencias (p=0,50). Sin embargo, en el suero de las puérperas control, la concentración de α-tocoferol fue 1.059,5±72,7µg/dL y, en las diabéticas, 1.391,4±531,5µg/dL, con p<0,01). No hubo correlación entre la concentración de α-tocoferol en el suero y en el calostro para el Grupo Control. Resultado semejante fue encontrado para el grupo con diabetes mellitus gestacional. CONCLUSIONES: Los grupos presentaron estado nutricional adecuado respecto...

Avaliar e comparar a concentração de α-tocoferol no leite colostro e no soro de mães diabéticas e saudáveis. MÉTODOS: Estudo transversal, realizado com 51 parturientes voluntárias, sendo 20 diagnosticadas com diabetes melito gestacional e 31 sem nenhuma doença associada. Coletaram-se as amostras de soro e de colostro em jejum no pós-parto imediato e o α-tocoferol foi analisado por cromatografia líquida de alta eficiência (CLAE). Para definir o estado nutricional de vitamina E, adotou-se ponto de corte sérico (697,7µg/dL). O teste t de Student para variáveis independentes comparou as concentrações médias de α-tocoferol no soro e no colostro entre os grupos controle e com diabetes melito gestacional. A correlação de Pearson testou a relação entre a concentração de α-tocoferol no soro e no colostro para ambos os grupos. As diferenças foram consideradas significantes quando p<0,05. RESULTADOS: As concentrações de α-tocoferol no colostro foram 1.483,1±533,8µg/dL para as mulheres do Grupo Controle e 1.368,8±681,8µg/dL para as diabéticas, não havendo diferenças (p=0,50). Entretanto, no soro das puérperas controle, a concentração de α-tocoferol foi 1.059,5±372,7µg/dL e, nas diabéticas, 1.391,4±531,5µg/dL, com p<0,01. Não houve correlação entre a concentração de α-tocoferol no soro e no colostro para o Grupo Controle. Resultado semelhante foi encontrado para o grupo com diabetes melito gestacional. CONCLUSÕES: Os grupos apresentaram estado nutricional adequado quanto à vitamina E. Não houve associação entre diabetes melito gestacional e mudanças na concentração de α-tocoferol no colostro...