The feeding of escessive amounts of vitamin D to animals causes pathological changes in the skeleton and calcification of soft tissues (l-4). Hypervitaminosis A causes bone fragility. Spontaneous fractures occur in growing rats, whereas in the adult rat only rarefaction develops (5-8). Although excesses of each vitamin cause specific pathological changes, the concomitant feeding of toxic amount...

Vitamin A deficiency results in multiple derangements that impair the response to infection. This review focuses on experimental models of specific virus infections and on cytokines and cells with cytolytic activity important to antiviral defenses. Altered specific antibody responses and greater epithelial damage in vitamin A-deficient hosts are consistent findings. The cytolytic activity of na...

β-Carotene-rich orange sweet potato (OSP) has been shown to improve vitamin A status of infants and young children in controlled efficacy trials and in a small-scale effectiveness study with intensive exposure to project inputs. However, the potential of this important food crop to reduce the risk of vitamin A deficiency in deficient populations will depend on the ability to distribute OSP vine...

Vitamin B12 (cobalamin) is an essential coenzyme for nucleic acid synthesis. Animal protein is the major dietary source of vitamin B12. Deficiency of vitamin B12 leads to megaloblastic anemia, degeneration of the brain, spinal cord, peripheral nerves, and abnormalities of epithelial tissues. Two factors are necessary for the cure of megaloblastic anemia: one in food (extrinsic factor) and one i...

Night vision was tested electroretinographically and psychophysically in a vitamin A deficient patient before and after therapy. Vitamin A deficiency resulted from malabsorption due to a jeujunoileal bypass operation. Before therapy the patient had severely reduced cone and rod function. After the reversal operation, accompanied by 5 injections of a total of 500,000 units of vitamin A, complete...

OBJECTIVES To identify the prevalence of zinc deficiency in a population with high prevalence of vitamin A deficiency; to verify whether zinc deficiency is associated with vitamin A deficiency in the population studied; to verify risk factors for zinc deficiency (sex, age, diarrhea and fever). METHOD Cross-sectional study of 182 healthy children aged > or = 24 months and < 72 months. Peripher...

BACKGROUND Bacterial vaginosis (BV) in pregnancy is linked to preterm birth, but its risk factors are not well understood. Micronutrient deficiencies may be associated with an increased risk of this condition. OBJECTIVE We assessed the effect of weekly vitamin A or β-carotene supplementation during pregnancy until 3 mo postpartum on BV risk in rural northeastern Bangladesh. DESIGN In this c...

OBJECTIVE To quantify vitamin A levels in mature milk of 196 nursing women who were treated at the Maternity School of Rio de Janeiro and to evaluate its correlation with sociodemographic variables and degree of nutrition knowledge. METHODS To quantify retinol concentrations, 10 mL of mature milk were collected by manual expression of one breast, 2 hours after the last feed, in the morning pe...

In mid-1993 Ecuador's Health Research Institute conducted a survey to evaluate the general nutrition and vitamin A status of children in five provinces (three in the mountains and two on the coast) containing pockets of extreme poverty. The survey enrolled 1555 children 12-59 months old who constituted a multi-phased stratified cluster sample obtained by random selection methods. Among its othe...

BACKGROUND Vitamin A deficiency is a major public health nutrition problem, affecting an estimated 190 million preschool-aged children and 19 million pregnant and lactating women globally, and 83 million adolescents in Southeast Asia alone. Its consequences (disorders) include xerophthalmia (the leading cause of early childhood blindness), increased severity of infection, anemia, and death. Bec...