Effects of ethanol intake on retinol concentration in the milk of lactating rats

The effect of the consumption of ethanol (5%) on retinol concentration in milk was studied in the rat on day 12 after delivery, together with the evolution of dam body weight and pup growth rate. Female Wistar rats receiving alcohol (5%) in drinking water during lactation (N = 7) were compared to normal controls fed ad libitum (N = 6). The mean maternal alcohol intake was 3.96 ± 0.23 g/kg body weight per day. To determine retinol levels in milk we used the Bessey and Lowry method, modified by Araújo and Flores ((1978) Clinical Chemistry, 24: 386-392). The pups were separated from dams for a 2-4-h period, after which the dams were injected intraperitoneally with anesthetic and oxytocin. The concentration of retinol in milk was 162.88 ± 10.60 µg/dl in the control group and 60.02 ± 8.22 µg/dl in the ethanol group (P<0.05). The ethanol group consumed less food than the controls and lost a significant amount of weight during lactation. On days 8, 10 and 12, the body weight of the pups from rats given ethanol (13.46 ± 0.43, 16.12 ± 0.48 and 18.60 ± 0.91 g, respectively) were significantly lower (P<0.05) than the weight of pups from controls (15.2 ± 0.44, 18.36 ± 0.54, 20.77 ± 0.81 g). These data show that ethanol intake during the suckling period, even at low concentrations, decreases the amount of retinol in milk and, therefore, the amount available to the pups

Retinol sérico de adolescentes de uma escola da cidade de São Paulo Retinol blood levels in high school students of São Paulo, Brazil

OBJETIVO: Investigar os níveis séricos de retinol de 218 adolescentes de ambos os sexos com idade entre 10 e 19 anos, matriculados em colégio da rede privada de ensino da cidade de São Paulo, foi o objetivo deste trabalho. MÉTODOS: Para a avaliação da condição nutricional dos adolescentes, utilizaram-se as medidas antropométricas de peso e altura e também a história dietética. A dosagem de retinol foi realizada pela técnica de espectrofotometria, considerando como níveis séricos inadequados valores <1,05µmol/L (30µg/dL). RESULTADOS: A média de ingestão, de acordo com a faixa etária, foi maior que a recomendação, porém com altos valores de desvios padrão, em ambos os sexos. A prevalência de adolescentes com níveis séricos de vitamina A abaixo do adequado foi de 30% em ambos os sexos e a análise da correlação de Índice de Massa Corporal com os níveis séricos de retinol não mostrou significância, como também a análise da correlação entre a densidade de ingestão de vitamina A e níveis séricos de retinol. CONCLUSÃO: Os achados deste estudo sugerem a necessidade da realização de mais investigações sobre vitamina A no período da adolescência, para verificar se o nível sérico baixo desse nutriente é um fator de risco para a saúde do adolescente ou é reflexo da captação acelerada que ocorre para atender necessidades metabólicas.<br>OBJECTIVE: The purpose of the study was to examine plasma retinol levels in 218 adolescents of both sexes, ages 10 to 19 years old. All the subjects attended a private high school in the city of São Paulo. METHODS: In order to evaluate the students' nutritional condition, the researchers performed anthropometrical measurements - weight and height - in addition to investigating the subjects' diet history. The retinol level was measured through the spectrophotometer technique, considering as inadequate values of concentration under <1.05µmol/L (30µg/dL). RESULTS: The results indicate that the average intake, according to the age range, was higher than recommended, even though presenting high deviation patterns for both genders. The percentage of teenagers with plasma concentrations of vitamin A under the adequate level was 30% for both genders, and neither the analysis of the correlation between Body Mass Index and plasma concentrations of retinol, nor the analysis of the correlation between the density of vitamin A intake and plasma concentration of retinol, were significant. CONCLUSION: The research findings point out to the need for further investigation of vitamin A concentrations during adolescence, in order to check more accurately whether the low plasma concentration of this nutrient should be considered a risk factor, or the result of the accelerated absorption which takes place in adolescence to fulfill the metabolic requirements characteristic of this period of human growth

Níveis séricos de retinol em escolares de 7 a 17 anos no município do Rio de Janeiro Serum retinol levels in school children, 7 to 17 years old in Rio de Janeiro, Brazil

OBJETIVO: Avaliar o estado nutricional quanto à vitamina A em escolares de 7 a 17 anos. Foram analisados 574 escolares, com idade entre 7 e 17 anos, regularmente matriculados na rede municipal de ensino no Rio de Janeiro. MÉTODOS: Os níveis séricos de retinol foram determinados pelo método Bessey-Lowry modificado e o ponto de corte utilizado para caracterizar inadequação sérica de retinol foi <1,05µmol/L. RESULTADO: Encontrou-se um total de 10,30% de escolares com baixos níveis de retinol sérico. Ao considerar a faixa etária, observou-se uma tendência a maiores percentuais de níveis inadequados de retinol sérico entre escolares mais jovens (11,98% na faixa etária de 7 a 10 anos e 7,92% na faixa etária de 10 a 17 anos). CONCLUSÃO: Ainda que os níveis séricos de retinol tendam a elevar-se com a idade, eles ainda são baixos com freqüência suficiente para justificar maior atenção ao segmento populacional mais jovem e tornar pertinente a sua inclusão em programas de combate às deficiências de micronutrientes.<br>OBJECTIVE: The vitamin A nutritional status assesment in scholars whose age is from 7 to 17 years old is the aim of this study. Data from 574 scholars have been analyzed, they were from 7 to 17 years old, and matriculated in the public educational system of Rio de Janeiro. METHODS: The serum retinol levels were assessed by the modified Bessey-Lowry method and the reference point to qualify the inadequate serum retinol level was <1,05µmol/L. RESULTS: The current study has identified that 10.30% of the scholars have presented low serum retinol levels. Considering the age group, the study shows that the younger scholars can present highier percentages of inadequate serul retinol levels (11.98% for those who is 7 to 10 years old, and 7.92% for those who is from 10 to 17 years old). CONCLUSIONS: Although the serum retinol levels tends to raise according to the age, they are still low and its frequency is relevant to focus the atention to the youngest scholars, including them in micronutrients deficiency combat programs