Perspectives from micronutrient malnutrition elimination/eradication programmes.
Micronutrient malnutrition cannot be eradicated, but the elimination and control of iron, vitamin A and iodine deficiencies and their health-related consequences as public health problems are currently the targets of global programmes. Remarkable progress is occurring in the control of goitre and xerophthalmia, but iron-deficiency anaemia (IDA) has been less responsive to prevention and control efforts. Subclinical consequences of micronutrient deficiencies, i.e. "hidden hunger", include compromised immune functions that increase the risk of morbidity and mortality, impaired cognitive development and growth, and reduced reproductive and work capacity and performance. The implications are obvious for human health and national and global economic and social development. Mixes of affordable interventions are available which, when appropriately adapted to resource availability and context, are proven to be effective. These include both food-based interventions, particularly fortification programmes, such as salt iodization, and use of concentrated micronutrient supplements. A mix of accompanying programmes for infection control, community participation, including education, communication and information exchange, and private sector involvement are lessons learned for overcoming deterrents and sustaining progress towards elimination. (+info)
Important micronutrient deficiencies in at-risk populations can be addressed simultaneously with programmatically cost-effective results. Because of the interaction between many micronutrients, this would also be biologically effective. With adequate investment and political support, the chances of eliminating iodine deficiency as a problem in women of reproductive age and young children and of eliminating vitamin A deficiency as a problem in young children in the future are high. To eliminate iron deficiency and folic-acid-dependent neural tube defects (FADNTDs) in low-income populations, a new set of approaches will have to be developed. These same approaches, if successful, could be used to tackle other important micronutrient deficiencies. (+info)
Separate and joint effects of micronutrient deficiencies on linear growth.
Recent studies have investigated the effect of micronutrient deficiencies on growth stunting, with special attention toward the effect of zinc, iron, vitamin A and iodine deficiencies. In Mexico, the prevalence of growth stunting in children <5 y old is approximately 24%; it is higher in rural areas and lower in urban areas. In an initial study, the effect of zinc and/or iron supplementation on linear growth was investigated in a longitudinal, placebo-controlled design. After 12 mo of supplementation, there was no difference between the groups supplemented with zinc, iron or zinc plus iron and the placebo group. At baseline, 82% of the children in this study were deficient in at least two out of the five micronutrients that were determined, and 73% were anemic. In another study, a mixture of those micronutrients that were documented to be lacking in Mexican children was formulated in a supplement and given to Mexican children over a period of 12 mo in a longitudinal, placebo-controlled, supplementation design. Children in the low and medium socioeconomic status grew about 1 cm more than similar children in the placebo group. This difference was not found in children of high socioeconomic status. It is suggested that, in most cases, growth stunting is associated with marginal deficiencies of several micronutrients and that in populations with multiple micronutrient deficiencies, the effect on linear growth of supplementation with single nutrients will not be significant. Supplementation with multiple micronutrients is expected to be more effective, but even in that case the actual increment in height was less than the expected potential increment. (+info)
Effect of iron-, iodine-, and beta-carotene-fortified biscuits on the micronutrient status of primary school children: a randomized controlled trial.
BACKGROUND: Deficiencies of iron, iodine, and vitamin A are prevalent worldwide and can affect the mental development and learning ability of schoolchildren. OBJECTIVE: The aim of this study was to determine the effect of micronutrient-fortified biscuits on the micronutrient status of primary school children. DESIGN: Micronutrient status was assessed in 115 children aged 6-11 y before and after consumption of biscuits (fortified with iron, iodine, and beta-carotene) for 43 wk over a 12-mo period and was compared with that in a control group (n = 113) who consumed nonfortified biscuits. Cognitive function, growth, and morbidity were assessed as secondary outcomes. RESULTS: There was a significant between-group treatment effect on serum retinol, serum ferritin, serum iron, transferrin saturation, and urinary iodine (P <0.0001) and in hemoglobin and hematocrit (P <0.05). The prevalence of low serum retinol concentrations (<0.70 micromol/L) decreased from 39.1% to 12.2%, of low serum ferritin concentrations (<20 microg/L) from 27.8% to 13.9%, of anemia (hemoglobin <120 g/L) from 29.6% to 15.6%, and of low urinary iodine concentrations (<100 microg/L) from 97.5% to 5.4%. There was a significant between-group treatment effect (P <0.05) in cognitive function with the digit span forward task (short-term memory). Fewer school days were missed in the intervention than in the control group because of respiratory- (P = 0.097) and diarrhea-related (P = 0.013) illnesses. The intervention had no effect on anthropometric status [corrected]. CONCLUSIONS: Fortified biscuits resulted in a significant improvement in the micronutrient status of primary school children from a poor rural community and also appeared to have a favorable effect on morbidity and cognitive function [corrected]. (+info)
Bioavailability of biotin given orally to humans in pharmacologic doses.
BACKGROUND: Patients with carboxylase deficiency are treated with pharmacologic doses of biotin. OBJECTIVE: We sought to determine the bioavailability of biotin at pharmacologic doses. DESIGN: Biotin was administered orally (2.1, 8.2, or 81.9 micromol) or intravenously (18.4 micromol) to 6 healthy adults in a crossover design with > or =2 wk between each biotin administration. Before and after each administration, timed 24-h urine samples were collected. Urinary biotin and biotin metabolites were analyzed by an HPLC avidin-binding assay. RESULTS: Urinary recoveries of biotin plus metabolites were similar (approximately 50%) after the 2 largest oral doses and the 1 intravenous dose, suggesting 100% bioavailability of the 2 largest oral doses. For unexplained reasons, the apparent recovery of the smallest oral dose was about twice that of the other doses. For all 4 doses, biotin accounted for >50% of the total of biotin and biotin metabolites in urine. Bisnorbiotin (13-23%), biotin-d,l-sulfoxide (5-13%), bisnorbiotin methyl ketone (3-9%), and biotin sulfone (1-3%) accounted for the remainder. The percentage excretion of biotin was greater when biotin was administered intravenously and for the largest oral dose than for the 2 smallest oral doses. CONCLUSION: Our data provide evidence that oral biotin is completely absorbed even when pharmacologic doses are administered. Biotin metabolites account for a substantial portion of total urinary excretion and must be considered in bioavailability studies. We speculate that renal losses of biotin (as a percentage of the dose administered) are moderately elevated when pharmacologic doses of biotin are administered. (+info)
Nutrient intake of food bank users is related to frequency of food bank use, household size, smoking, education and country of birth.
The number of individuals and families accessing food assistance programs has continued to grow throughout the 1990s. Despite the increased health risk among low-income people, few studies have addressed nutrient intake throughout the month or at the end of the month when food and financial resources are thought to be compromised, and no study has described dietary status of a random sample of food bank users. Nutrient intakes of adult female and male food bank users in metropolitan Montreal, Quebec, Canada, were monitored week-by-week over a month by dietitian-administered 24-h recall interviews. A total of 428 participants from a stratified random sample of 57 urban area food banks completed all four interviews. Mean energy intake, as an indicator of diet quantity, was similar to other adult populations (10.2 +/- 4.8 and 7.9 +/- 3.6 MJ for men and women, respectively, age 18-49 y) and not related to sociodemographic variables except the expected biological variation of age and sex. Macronutrient intake was stable throughout the month. Overall median intakes of calcium, vitamin A, and zinc were below recommended levels for all age and sex groups. Intakes of several micronutrients were related to frequency of food bank use, household size, smoking, education, and country of birth. High nutrient intake variability characterized these adult food bank users. (+info)
Energy intake and micronutrient intake in elderly Europeans: seeking the minimum requirement in the SENECA study.
OBJECTIVE: To examine energy intake of elderly people participating in the Survey in Europe on Nutrition and the Elderly, a Concerted Action (SENECA) study in relation to the adequacy of micronutrient intake. DESIGN: Data from eight countries on 486 men and 519 women who were 74-79 years old. Dietary intakes of energy, iron, thiamine, riboflavin and pyridoxine were calculated. RESULTS: There was inadequate intake of one or more nutrients in 23.9% of men and 46.8% of women. The prevalence of inadequate intakes decreased gradually with higher energy intakes. Of all people with energy intakes exceeding 1500 kcal, 19% of men and 26% of women still had an inadequate intake of at least one micronutrient. CONCLUSION: We found no single criterion ensuring level of energy intake with an adequate micronutrient supply. The prevalence of an inadequate intake of micronutrients was high at all energy intake levels, especially in women. (+info)
Functional biochemical and nutrient indices in frail elderly people are partly affected by dietary supplements but not by exercise.
A decline in dietary intake due to inactivity and, consequently, development of a suboptimal nutritional status is a major problem in frail elderly people. However, benefits of micronutrient supplementation, all-round physical exercise or a combination of both on functional biochemical and hematologic indicators of nutritional and health status in frail elderly subjects have not been tested thoroughly. A 17-wk randomized controlled trial was performed in 145 free-living frail elderly people (43 men, 102 women, mean age, 78 +/- 5.7 y). Based on a 2 x 2 factorial design, subjects were assigned to one of the following: 1) nutrient-dense foods, 2) exercise, 3) both (1) and (2) or 4) a control group. Foods were enriched with micronutrients, frequently characterized as deficient [25-100% of the recommended daily allowance (RDA)] in elderly people. Exercises focused on skill training, including strength, endurance, coordination and flexibility. Dietary intake, blood vitamin levels and nutritional and health indicators, including (pre)albumin, ferritin, transferrin, C-reactive protein, hemoglobin and lymphocytes were measured. At baseline, 28% of the total population had an energy intake below 6.3 MJ, up to a maximum of 93% having vitamin intakes below two thirds of the Dutch RDA. Individual deficiencies in blood at baseline ranged from 3% for erythrocyte glutathione reductase-alpha to 39% for 25-hydroxy vitamin D and 42% for vitamin B-12. These were corrected after 17 wk in the two groups receiving the nutrient-dense foods, whereas no significant changes were observed in the control or exercise group. Biochemical and hematologic indicators at baseline were within the reference ranges (mean albumin, 46 g/L; prealbumin, 0.25 g/L; hemoglobin, 8.6 mmol/L) and were not affected by any of the interventions. The long-term protective effects of nutrient supplementation and exercise, by maintaining optimal nutrient levels and thereby reducing the initial chance of developing critical biochemical values, require further investigation. Other indicative functional variables for suboptimal nutritional status, in addition to those currently selected, should also be explored. (+info)