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Summary
There is significant scientific agreement that human milk is the best source of nutrients for the human infant. In addition it is also agreed that the constituents of human milk and their concentrations should form the basis of infant formula compositions. The objectives of this review are two fold: to examine the data on the long chain polyunsaturated fatty acid levels (LC-PUFA) in human milk and the rationale for inclusion of these lipids in infant formulas; secondly, as a consequence of addition of highly unsaturated lipids to infant formulas, the antioxidant requirements are increased. Therefore the effect of the addition of LC-PUFA on infant vitamin E status is also examined.
Keywords
Docosahexaenoic acid, Arachidonic acid, Infant formula, Preterm infants, Term infants, Antioxidants
International Journal for Vitamin and Nutrition Research,
Band 67, 1997, Heft 4 © Verlag Hans Huber, Bern
Summary
Plasma vitamin A responses were examined in 30 low income pregnant women before and after supplementation with vitamin A. In the groups of women who had an initial (at <20 weeks) plasma vitamin A of less than 30 mg/dl retinol, typical changes representing a peak at mid gestation and a significant decline at term were observed. Supplementation with vitamin A tablets equivalent to 1800 mg of retinol daily for 12 weeks was able to raise the plasma vitamin A content at term. On the other hand, those women who had an initial plasma vitamin A concentration of more than 30 mg/dl did not show any appreciable changes even with vitamin A supplementation. Consistent beneficial effects of supplementation on maternal and cord vitamin A and maternal hemoglobin and progesterone were noted in our previous studies only when the supplementation lasted for 12 weeks and not after 10 weeks. Using these data with dietary intake obtained from other studies, an attempt was made to estimate the requirements of vitamin A during pregnancy. The approximate requirement of 780 retinol equivalents (RE) obtained, is in agreement with earlier recommendations of FAO and Indian Council of Medical Research (ICMR) Expert Committees, but is higher than the recent ICMR recommendations.
Keywords
Vitamin A, Pregnancy, Vitamin A supplementation, Plasma profile, Requirements
International Journal for Vitamin and Nutrition Research,
Band 67, 1997, Heft 4 © Verlag Hans Huber, Bern
Summary
The mechanism by which vitamin A prevents or delays chemical carcinogenesis remains unclear. In addition to these antimutagenic and antiproliferative activities, vitamin A seems able to induce programmed cell death. In this study, we assess the suggested role of vitamin A on the in vitro apoptosis induction in a rat colonic tumor cell line. Several concentrations of retinyl palmitate were added in the culture media. We observed cell proliferation by measuring the (3H)thymidine incorporation, cell differentiation by measuring the intestinal alkaline phosphatase expression, and apoptosis induction by DNA fragmentation and morphological evolution of adherent and floating cells. The results show that vitamin A decreases (3H)thymidine incorporation after 1 day of treatment, induces alkaline phosphatase expression, and increases the number of cells falling in apoptosis. This report confirms the role of vitamin A on the induction of cell differentiation, on the inhibition of cell proliferation and shows the vitamin A capacity to induce apoptosis. These results could be attractive to prevent development of colon cancer by vitamin A supplemented diets.
Keywords
Vitamin A, Apoptosis, Proliferation, Differentiation, Rat colonic tumor cell, Colon cancer
International Journal for Vitamin and Nutrition Research,
Band 67, 1997, Heft 4 © Verlag Hans Huber, Bern
Summary
To determine the influence of vitamin E on phylloquinone activity, one day-old chicks were raised on a masch diet supplemented with different amounts of vitamin E for 31 days. In chicks fed a diet high in vitamin E (4000 mg all-rac-a-tocopheryl acetate/kg) but adequate in vitamin K (0.14 mg phylloquinone/kg) a threefold increase in prothrombin time and an increase in mortality rate (five out of twelve animals died from increased bleeding tendency) was observed. The inhibiting effect of high dietary vitamin E on procoagulant factors could be prevented by increasing dietary phylloquinone supplementation. Weight development, and feed utilization were insignificantly different in chicks fed different amounts and ratios of vitamins E and K1. Plasma and liver a-tocopherol levels correlated with dietary amounts of vitamin E. Increased phylloquinone levels in the diet did not significantly influence a-tocopherol concentrations in plasma and liver, but coagulopathy caused by high vitamin E intake could be reversed.
Keywords
a-Tocopherol, Phylloquinone, Vitamin E/K1 interactions, Coagulation factors
International Journal for Vitamin and Nutrition Research,
Band 67, 1997, Heft 4 © Verlag Hans Huber, Bern
Summary
This investigation was designed to examine the effect of dietary thiamin supply during gestation on body thiamin status of lactating rats and their suckling offspring, and thiamin in milk from 1 to 13 days postpartum. Therefore, a study over two generations was conducted feeding 2, 6.7 and 20 mg/kg thiamin during gestation and 8 mg/kg thiamin during lactation. Rat dams receiving inadequate thiamin during gestation and their offspring were thiamin-deficient on the basis of reduced activity of transketolase in blood and erythrocytes, which did not reach completely the control level even two weeks postpartum. The thiamin intake during gestation influenced significantly the thiamin levels in tissues of the dams and their offspring. However, the observed dose-dependence remained only for the first days of lactation. The thiamin concentration in milk two days postpartum also reflected the nutritional thiamin status from the pregnant rats, in which the thiamin concentration raised continuously with the duration of the lactation cycle. The data indicate that an adequate thiamin supply during lactation can not completely compensate for an inadequate thiamin supply during gestation, and that necessitates a constant thiamin intake.
Keywords
Dietary thiamin supply, Gestation, Lactation, Thiamin status, Milk, Rat
International Journal for Vitamin and Nutrition Research,
Band 67, 1997, Heft 4 © Verlag Hans Huber, Bern
Summary
Ascertaining the antioxidant nutritional status of different
population groups is of great interest because of the probable
benefits of these nutrients in the prevention of chronic diseases. In
this study the vitamin C status of adults living in a region
characterized by its high availability of food with a high vitamin C
content was investigated. In addition, vitamin C intake and the
effect of non-nutritional factors on plasma vitamin C was
examined.
The majority of the subjects had an adequate vitamin C status.
Nevertheless, by a probabilistic method it was established that a
large proportion of the population was at risk of consuming
inadequate amounts of vitamin C, the risk being considerably higher
among male smokers. Females had higher vitamin C plasma
concentrations than men. This difference persisted after adjusting
the data for smoking habits. Also women's vitamin C intake was
higher. Smoking affected male's plasma vitamin C concentrations
negatively. Neither age nor the season of data collection had an
effect on plasma vitamin C. Vitamin C intake was only influenced by
season among males. No factor affected significantly vitamin C intake
or plasma vitamin concentrations among females.
Finally, multiple linear regression analysis showed that vitamin C
intake and smoking habits make it possible to predict, in part,
plasma vitamin C concentrations in males.
Keywords
Vitamin C, Ascorbic acid, Nutritional status, Vitamin C plasma concentration, Vitamin C intake
International Journal for Vitamin and Nutrition Research,
Band 67, 1997, Heft 4 © Verlag Hans Huber, Bern
Summary
The vitamin C status of patients with chronic renal failure (CRF), dialysis patients (DP) and patients after renal transplantation (RT) was the object of this investigation. Levels of vitamin C intake from dietary records were estimated at mean values of 93.5 mg/d (CRF), 65.5 mg/d (DP) and 163.9 mg/d (RT). Compared to the recommendation of the German Society of Nutrition (75 mg/d), this indicated a normal range of supply for all groups except the group of DP. The corresponding mean plasma concentrations were 62.2 mmol/l (CRF), 80.3 mmol/l (DP) and 68.8 mmol/l (RT). Supplements of 60 or 100 mg vitamin C given to patients of the DP-group after each dialysis session showed slightly, but not significantly higher concentrations of vitamin C in plasma. During dialysis treatment, plasma vitamin C concentrations dropped to approximately 50% of the basal value, but almost reached initial levels again 44 hours later, both with and without supplementation. During one treatment period, vitamin C loss in the dialysate of three patients ranged between 92.5 and 333.6 mg. The amount of vitamin C in plasma, however, dropped to approximately 50% of the basal value for these patients, too.
Keywords
Ascorbic acid, Renal failure, Renal transplantation, Dialysis, Vitamin supplementation
International Journal for Vitamin and Nutrition Research,
Band 67, 1997, Heft 4 © Verlag Hans Huber, Bern
Summary
Serum vitamins A (retinol) and E (alpha-tocopherol), beta-carotene, zinc and selenium, and related proteins for 157 children with newly diagnosed and histologically proven malignancy were compared with those of 632 cancer-free controls. Incident cancer cases and controls were 1 - 16 years of age and recruited in 1986 - 1989. Age and sex-adjusted serum concentrations of beta-carotene and alpha-toco- pherol were significantly inversely associated with cancer. No significant association with cancer was observed for serum values of selenium. Although low levels of antioxidants might in part be involved through a causality link, the reported decreased peripheral nutrient levels are considered rather as an impairment of the body's defence system, occurring during the cancer-related metabolic and nutritional disturbances and inflammation processes. The cancer cases group was followed-up and examined 6 months after diagnosis. Among the 157 subjects, 24 had died and 133 were reported to be alive. No substantial difference for any antioxidant or chemistry variable at onset was observed as a function of clinical outcome and health status.
Keywords
Antioxidants, Childhood neoplasms, Acute-phase reactants, Vitamin A, Vitamin E, Selenium, Zinc
International Journal for Vitamin and Nutrition Research,
Band 67, 1997, Heft 4 © Verlag Hans Huber, Bern
Summary
This study examined the incorporation of docosahexaenoic acid (DHA) from several dietary sources into the brain tissue and intracellular organelles in mice which had been fed a 5% palm oil (low n-3 fatty acid level) diet for 8 or 11 weeks. The percentages of DHA in the tissues of mice fed 5% representative oils for 30 days or 5% purified n-3 fatty acid diets for 6 days were analyzed using gas chromatography. The percentage of DHA in the brain was ranked in the following order: the salmon oil diet group > the sardine oil diet group "the perilla oil diet group" the lard and palm oil diet groups for the 30 day feeding trial; and the DHA diet group "the eicosapentaenoic acid and a-linolenic acid diet groups for the 6 day feeding trial. The percentage of arachidonic acid showed a more dramatic decrease than that of docosapentaenoic acid. These results reflected the plasma fatty acid concentrations, but were not as pronounced as the changes observed in the plasma. The majority of the DHA incorporated into the brain was recovered in microsomal, synaptosomal, and mitochondrial fractions separated by density gradient centrifugation. These membrane fractions took up DHA within several days. These results suggest that the intake of DHA itself increases the DHA level of brain membranes more rapidly than intake of the precursors in animals fed a low n-3 fatty acid level diet.
Keywords
Dietary lipids, Docosahexaenoic acid, Brain, Microsomes, Synaptosomes, Mitochondria, Adult mouse
International Journal for Vitamin and Nutrition Research,
Band 67, 1997, Heft 4 © Verlag Hans Huber, Bern