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Antioxidant micronutrient profile (vitamin E, C, A, copper, zinc, iron) of colostrum: association with maternal characteristics.

The study was conducted to investigate the micronutrient profile of human colostrum, and to assess the association of maternal characteristics to the micronutrients. Colostral concentrations of antioxidant vitamins E, C, and A were 21.34 +/- 8.47, 148.92 +/- 43.64, 0.79 +/- 0.42 micromol/l, respectively. The antioxidant minerals copper, zinc, and iron contents were 19.17 +/- 11.73, 63.69 +/- 12.82, 11.44 +/- 1.46 micromol/l, respectively. Maternal characteristics did not have any influence on the colostral micronutrients.

Adolescent↗

Micronutrient levels in HIV-1-infected children.

OBJECTIVE: Micronutrients (zinc, copper, selenium, vitamin A, E, and carotenoids) are essential for the integrity of host defences. This study was designed to determine the prevalence of abnormalities of the micronutrient levels in HIV-1-seropositive children. DESIGN: Prospective study. SETTING: The study was performed on HIV-1-infected children at the Paediatric Haematology and Oncology Unit of Toulouse Hospital, France. PATIENTS: Twenty-one children, suffering from HIV-1 infection and 21 control subjects of similar age (2-9 years) were included in the study. In the HIV-1-infected children, two subgroups were considered according to stage (non-AIDS or AIDS), based on the Centers for Disease Control and Prevention 1987 criteria. RESULTS: The first statistically significant deficiencies occurred at non-AIDS stage and were confirmed at AIDS stage: P < 0.05 for lycopene, retinol, tocopherol and P < 0.001 for transthyretin and serum albumin. Levels of copper (40%) and long-chain polyunsaturated fatty acids (21%) were higher in the non-AIDS group than the controls. CONCLUSION: Biological impairing of the micronutrient levels was observed in the non-AIDS stage without clinical sign. This information is useful in delineating eventual and well considered nutritional intervention strategies that may improve the clinical status of HIV-1-infected children and perhaps alter the course of their disease.

Carotenoids↗

Micronutrients and breast cancer.

A large part of the epidemiological debate on diet and breast cancer has been dominated by the issue of whether fat, particularly animal fat, increases risk. Lately, the possible protective effect of various dietary constituents has received more attention. Vitamins C and E, and beta-carotene have antioxidant activity and may thus provide a cellular defence against reactive oxygen species that damage DNA. Dietary fibre may influence oestrogen metabolism. A large case-control study (2,569 breast cancer and 2,588 hospital controls) conducted in six Italian areas between 1991 and 1994 suggested that a diet rich in several micronutrients was associated with significantly lowered risk. After allowance for non-dietary risk correlates, energy intake and the mutual confounding effect of the various micronutrients, beta-carotene, vitamin E and calcium were associated with odds ratios in the highest intake quintile compared to the lowest one of 0.84, 0.75 and 0.81, respectively. Among different types of fibre, only cellulose intake showed a moderate inverse association. Evidence from other studies suggests that a favourable role of some micronutrients is possible, albeit probably less important than for cancers of the stomach and colon-rectum. Indeed, the relationship between fruit and vegetable intake is also less marked/consistent for breast cancer than for other sites. Among agents that have only recently been investigated, isoflavones, which are weak oestrogens, are of particular interest.

Ascorbic Acid↗

Review article: is there a link between micronutrient malnutrition and Helicobacter pylori infection?

Helicobacter pylori causes a chronic gastric infection, which is usually life-long. Many epidemiological studies have shown that this is probably one of the most common bacterial infections throughout the world involving 30% of the population living in developed countries and up to 80-90% of the population in developing regions. Concomitantly, developing regions also have high prevalence of micronutrient malnutrition. In the last few years, some studies have suggested that H. pylori infection may affect the homeostasis of different micronutrients including iron, vitamin B12, folic acid, alpha-tocopherol, vitamin C and beta-carotene. In this article, we discuss the current scientific information of the effect that H. pylori infection may produce on micronutrient malnutrition.

Helicobacter Infections↗

Can a short period of micronutrient supplementation in older institutionalized people improve response to influenza vaccine? A randomized, controlled trial.

OBJECTIVES: To test the hypothesis that a micronutrient supplement can improve seroconversion after influenza immunization in older institutionalized people. DESIGN: : Randomized, double-blind, placebo-controlled study. SETTING: Nursing and residential homes in Liverpool, United Kingdom. PARTICIPANTS: One hundred sixty-four residents aged 60 and older from 31 homes were initially randomized; of these, 119 (72.6%) completed the study. INTERVENTION: Participants were randomized to receive a micronutrient supplement providing the reference nutrient intake for all vitamins and trace elements or identical placebo. Tablets were taken over an 8-week period during September and October 2000; influenza vaccine was administered 4 weeks after their commencement. MEASUREMENTS: The hemagglutination-inhibiting antibody response as defined by a fourfold or greater titer rise over 4 weeks and assessed separately for each of the three antigens contained in the 2000/2001 influenza vaccine (A/New Caledonia/20/99 (H1N1), A/Moscow/10/99 (H3N2), B/Beijing/184/93 (B)). RESULTS: Despite a significant increase in serum concentrations of vitamins A, C, D3, E, folate, and selenium in the supplemented group, there was no significant difference between groups (supplemented vs placebo, respectively) in the proportion of participants seroconverting to H1N1 (41% vs 49%, P=.374), H3N2 (49% vs 58%, P=.343), or B (41% vs 40%, P=.944). CONCLUSION: A micronutrient supplement providing the reference nutrient intake administered over 8 weeks had no beneficial effect on antibody response to influenza vaccine in older people living in long-term care.

Aged↗

Serum and colon mucosa micronutrient antioxidants: differences between adenomatous polyp patients and controls.

OBJECTIVES: Micronutrient antioxidants, by virtue of their free radical scavenging properties, are potential chemopreventive agents against colon cancer. Yet, little is known about the actual concentration of these antioxidants in colonic mucosa. It is also not known whether a relationship exists between serum and mucosal tissue antioxidant levels. Previous studies evaluating the occurrence of polyps after supplementation with vitamin E and beta-carotene have yielded mixed results. The aim of this study was to determine the concentrations of seven micronutrient antioxidants (alpha- and gamma-tocopherol, lutein, beta-cryptoxanthin, lycopene, and alpha- and beta-carotene) in colonic mucosa and to determine whether serum levels of each antioxidant could predict levels of that antioxidant in the right and left colon of patients with normal mucosa or in those with adenomatous polyps. METHODS: Mucosal tissue concentrations and serum levels of antioxidants were determined in 10 patients with adenomatous polyps and 15 control subjects (GI patients with normal colonic mucosa). Mucosal tissue samples were obtained from both the right and left colon in all patients. RESULTS: Patients with polyps similar serum antioxidant status similar to that of control. However, polyp patients had significantly lower concentrations of all seven antioxidants in both the right (p < 0.0070) and left colon (p < 0.0026) than did controls. Finally, serum antioxidant levels predict right and left colon antioxidant levels in controls but not in patients with polyps. CONCLUSIONS: Patients with adenomatous polyps have low levels of micronutrient antioxidants in their colon mucosa. Because the serum levels of these antioxidants were similar in controls and polyp patients, our findings suggest an increased level of free radical activity in patients with polyps compared to normal subjects.

Adenomatous Polyps↗

Physical exercise or micronutrient supplementation for the wellbeing of the frail elderly? A randomised controlled trial.

OBJECTIVE: To examine the effects of 17 weeks of physical exercise and micronutrient supplementation on the psychological wellbeing of 139 independently living, frail, elderly subjects (inactive, body mass index < or =25 or experiencing weight loss). METHODS: Participants (mean (SD) age 78.5 (5.7)) were randomly assigned to: (a) comprehensive, moderate intensity, group exercise; (b) daily micronutrient enriched foods (25-100% recommended daily amount); (c) both; (d) neither. A social programme and identical regular foods were offered as attention control and placebo. RESULTS: At baseline, moderate to low but significant correlations were found between general wellbeing scores and physical fitness (r = 0.28), functional performance (r = 0.37), and blood concentrations of pyridoxine (r = 0.20), folate (r = 0.25), and vitamin D (r = 0.23) (all p values < or =0.02), but not with physical activity levels and other blood vitamin concentrations. General wellbeing score and self rated health were not responsive to 17 weeks of exercise or nutritional intervention. CONCLUSION: Psychological wellbeing in frail elderly people was not responsive to 17 weeks of intervention with exercise and/or micronutrient enriched foods. The moderate but significant correlations between wellbeing and physical fitness and several blood vitamin concentrations at baseline suggest that changes in wellbeing may occur after long term interventions.

Activities of Daily Living↗

Micronutrients in health and disease.

Micronutrients play a central part in metabolism and in the maintenance of tissue function. An adequate intake therefore is necessary, but provision of excess supplements to people who do not need them may be harmful. Single micronutrient deficiency states are comparatively easily recognised and treated. Subclinical deficiency, often of multiple micronutrients, is more difficult to recognise, and laboratory assessment is often complicated by the acute phase response. Clinical benefit is most likely in those people who are severely depleted and at risk of complications, and is unlikely if this is not the case. There is little evidence for supplements leading to a reduction in the incidence of infections in the elderly population, in coronary artery disease, or in malignant disease. The best evidence for benefit is in critical illness, and in children in developing countries consuming a deficient diet. More clinical trials are required with good clinical outcomes to optimise intake in prevention and treatment of disease.

Deficiency Diseases↗

Deficiencies of micronutrients, altered bowel function, and quality of life during late follow-up after pancreaticoduodenectomy for malignancy.

BACKGROUND/AIM: A previous study in our unit showed an inadequate dietary intake of fat-soluble vitamins and energy after pancreaticoduodenectomy (PD). This study was designed to determine whether deficiencies in dietary intake of micronutrients lead to nutritional deficiencies and to examine the impact of dietary advice on nutrition, bowel function, and quality of life. METHODS: Ten patients who had undergone PD for malignant disease more than 6 months previously were studied at baseline and follow-up 8 weeks apart. Dietary intakes of energy, fat, and micronutrients were assessed by analysis of weighed food diaries, and serum vitamins and trace elements were measured at each visit. Quality of life questionnaires (EORTC QLQ30 and PAN 26) were answered, and a clinical assessment of the bowel function was made. Targeted dietary intervention was given, where indicated, and its impact on the study parameters was assessed at the second clinic visit. RESULTS: The patients were generally well nourished. Dietary deficiencies of fat-soluble vitamins were detected (vitamin A, n = 2; vitamin D, n = 10; vitamin E, n = 2), but these correlated with serum deficiency only for vitamin A. The selenium intake was borderline or insufficient in 6 patients' diet, with serum deficiencies in 4. Despite normal intakes of iron and zinc, half the patients showed serum deficiency. The bowel function was an important factor in quality of life, and symptoms improved in 3 patients with enzyme supplements and antidiarrhoeal medication. CONCLUSIONS: PD patients appear to be prone to a predictable set of micronutrient deficiencies that may be compounded by insufficient dietary intake. The bowel function is important to these patients, and it should be optimized with aggressive enzyme replacement. Dietary intervention appears to make little short-term impact in the areas studied.

Aged↗

Antioxidant micronutrients in major trauma and burns: evidence and practice.

There has been a growing interest in micronutrients as a result of their essential role in endogenous antioxidant defense mechanisms and immunity. Critically ill burn and trauma patients are characterized by an increased free radical production, which is proportional to the severity of the injury. In addition, they are at high risk of negative trace element balances, which contribute to the imbalance in endogenous antioxidant capacity and the extension of primary lesions. Although selenium, zinc, and vitamin C and E status are altered in all injured patients, patients with major burns are unique for having copper deficiency. In major burns, high-dose ascorbic acid for 24 hours achieves reduction of resuscitation fluid requirements by endothelial antioxidant mechanisms both in animal models and in 1 human trial. Supplementation trials in trauma and burns including selenium and zinc have shown that early provision of micronutrients improves recovery. Vitamin supplementation trials without selenium have not achieved definitive effects. The human studies show that reinforcing antioxidant defenses early in the course of major injury is rational and that substituting the large initial micronutrient losses of selenium and zinc is safe in trauma, as is the addition of copper in burns. The IV route seems the only way to deliver the doses required to obtain a clinical effect.

Antioxidants↗

Micronutrient assessment in long-term home parenteral nutrition patients.

Assessment of micronutrient status of patients requiring long-term parenteral nutrition (PN) continues to be a challenge for clinicians. The scientific literature primarily consists of small studies and case reports. There are no evidence-based guidelines available. Clinicians rely on clinical assessment according to the patient's disease process, medication regimen, physical examination, and history of nutrient intake to determine existence or risk of micronutrient deficiency and toxicity. This paper will examine current scientific evidence and existing recommendations for the micronutrient assessment and management of patients requiring long-term PN.

Humans↗

Multiple micronutrient deficiencies: future research needs.

There has been a rising current of calls for a moratorium on international nutritional research in favor of an investment in intervention programs, per se. The topic of multiple-micronutrient supplementation reviewed at the International Workshop on Multi-Micronutrient Deficiency Control in the Life Cycle (May 30-June 1, 2001) has confirmed once again, however, the intimate interaction between program development and a supporting agenda of applied research. The areas of research required to produce successful intervention programs include biologic availability, safety and efficacy, communications and behavior, effectiveness, cost-effectiveness (efficiency), and food and pharmaceutical technology. Attention to safety and surveillance for unintended adverse effects has acquired new relevance as we analyze the multi-center International Research on Infant Supplementation (IRIS) I studies. All professionals involved in research projects in this area must assure both the quality and reliability of investigations and adhere to the highest principles of ethical conduct of research in human studies. The fundamental principles of research design and hypothesis development, quality assurance, reliability of measurements, and sound and unbiased interpretation of findings apply to all experimental science, and must be guaranteed for this mission. Agencies, academic institutions, and industry alike must work to create a system in which researchers can uphold these standards, and realize at the same time that the area of multi-micronutrient supplementation in developing countries can be a fertile area for training future researchers.

Cost-Benefit Analysis↗

Efficacy trials of a micronutrient dietary supplement in schoolchildren and pregnant women in Tanzania.

Traditionally, the main strategies used to control micronutrient deficiencies have been food diversification, consumption of medicinal supplements, and food fortification. In Tanzania, we conducted efficacy trials using a dietary supplement as a fourth approach. These were randomized, double-blind, placebo-controlled efficacy trials conducted separately first in children and later in pregnant women. The dietary supplement was a powder used to prepare an orange-flavored beverage. In the school trial, children consumed 25 g per school day attended. In the pregnancy trial, women consumed the contents of two 25-g sachets per day with meals. This dietary supplement, unlike most medicinal supplements, provided 11 micronutrients, including iron and vitamin A, in physiologic amounts. In both trials we compared changes in subjects consuming either the fortified or the nonfortified supplement. Measures of iron and vitamin A status were similar in the groups at the baseline examination, but significantly different at follow-up, always in favor of the fortified groups. Children receiving the fortified supplement had significantly improved anthropometric measures when compared with controls. At four weeks postpartum, the breast milk of a supplemented group of women had significantly higher mean retinol content than did the milk of mothers consuming the nonfortified supplement. The advantages of using a fortified dietary supplement, compared with other approaches, include its ability to control several micronutrient deficiencies simultaneously; the use of physiologic amounts of nutrients, rather than megadoses that require medical supervision; and the likelihood of better compliance than with the use of pills because subjects liked the beverage used in these trials.

Beverages↗

Drinking to their health: social analysis of a micronutrient-fortified beverage field trial.

Anthropologic research was conducted among pregnant and lactating women in rural Tanzania in conjunction with clinical trials of a micronutrient-fortified beverage. Use of the beverage was examined through interviews and ethnographic observation in clinics and at home. Women liked the taste of the beverage, considered it beneficial to their health, preferred it to pills or injections, and most were willing and able to use it according to instructions. Most consumed the beverage according to schedule in the hope of improving pregnancy outcomes. However, public health facilities in Tanzania are not currently equipped to ensure regular delivery of micronutrient supplements, and many of the women with the worst nutrition profiles are also those who would be least able to purchase supplements on the open market. Successful distribution of micronutrient supplements in forms that appeal to consumers, such as a fortified beverage, will require programmatic attention to locally appropriate social marketing and to the challenges of reaching those with extremely low incomes.

Adult↗

Behavior-change trials to assess the feasibility of improving complementary feeding practices and micronutrient intake of infants in rural Bangladesh.

This study used simple rapid-assessment techniques to test the feasibility of increasing the consumption of complementary foods by infants by asking mothers to increase meal quantity or frequency or by altering the viscosity/energy density of the food. The feasibility of using micronutrient supplements either added directly to food or administered as liquid drops was also examined. The study was conducted in rural Bangladesh and involved four separate short-term behavioral change trials. Depending on the trial, fieldworkers recruited 30 to 45 infants 6 to 12 months of age. Following recommendations to increase the amount of food provided to infants, the mean intakes from single meals increased from 40 +/- 23 g on day 1 to 64 +/- 30 g on day 7 (p < 0.05). In a second trial, the mean meal frequency increased from 2.2 +/- 1.3 on day 1 to 4.1 +/- 1.3 on day 7 (p < 0.05). Provision of high-energy-density diets, prepared by decreasing viscosity with alpha-amylase or by hand-mashing rice and dhal into a paste before feeding, increased single-meal energy consumption from 54 +/- 35 kcal to 79 +/- 52 kcal or 75 +/- 37 kcal (p < 0.05), respectively. Both types of micronutrient supplements were well accepted and used according to recommendations. In conclusion, it was possible to change short-term child-feeding behaviors to promote increased food intake, mealfrequency, energy density, and micronutrient consumption. Because each of these interventions lasted for only about 1 week, however, the long-term sustainability of these changes is not known. Moreover, the effect of increased feeding of complementary foods on intakes of breastmilk and total daily consumption of energy and nutrients requires further study.

Bangladesh↗

Colorectal cancer protective effects and the dietary micronutrients folate, methionine, vitamins B6, B12, C, E, selenium, and lycopene.

The data reported here were obtained from the case-control arm of a large, comprehensive, population-based investigation of colorectal cancer incidence, etiology, and survival, the Melbourne Colorectal Cancer Study, conducted in Melbourne, Australia. This part of the case-control study was designed to identify dietary factors associated with colorectal cancer risk in 715 incident cases compared with 727 age/sex frequency-matched randomly chosen community controls, in which a quantitative assessment of all foods eaten was made. New data are presented on the potential of two groups of micronutrients as protective agents, namely, those involved in DNA methylation, synthesis, and repair (folate, methionine, and vitamins B6 and B12) and those with antioxidant properties (selenium, vitamins E and C, and lycopene). The adjusted odds ratios showed that for folate there was significant protection for rectal cancer in second and third quintiles of consumption but not for colon cancer, and this was similar for methionine consumption. Vitamin B6 consumption was significantly protective for both colon and rectal cancer at the higher quintiles, and this was similar for vitamin B12. Dietary selenium was significantly protective at middle quintiles of consumption at both cancer sites. Dietary vitamins E and C were statistically significantly protective for both colon and rectal cancer at all levels of consumption, and for both vitamins there was a dose-response effect of increasing protection, particularly so for colon cancer. Lycopene was not associated with colorectal cancer risk. A combined model included vitamins E, C, and B12 and selenium as micronutrients protective for colorectal cancer and folate, which, however, showed an increased risk at the highest level of consumption. These data support the proposition that a diet containing the dietary micronutrients involved in DNA methylation (folate, methionine, and vitamins B6 and B12) and some of those with antioxidant properties (selenium and vitamins E and C) may have a role to play in lowering colorectal cancer risk and also that such protection can be achieved by dietary means alone.

Antioxidants↗

Prevalence of micronutrient malnutrition worldwide.

Recent estimates indicate that globally over two billion people are at risk for vitamin A, iodine, and/or iron deficiency, in spite of recent efforts in the prevention and control of these deficiencies. The prevalence is especially high in Southeast Asia and sub-Saharan Africa, and pregnant women and young children are at greatest risk. Other micronutrient deficiencies of public health concern include zinc, folate, and the B vitamins. However, there is limited data on the actual prevalence of these deficiencies. Finally, in many settings, more than one micronutrient deficiency exists, suggesting the need for simple approaches that evaluate and address multiple micronutrient malnutrition.

Avitaminosis↗

Adverse outcomes of poor micronutrient status in childhood and adolescence.

The adverse effects of micronutrient deficiencies and excesses in children up to reproductive age are presented. A summary of risks and adverse functional and health outcomes associated with deficient and excessive intakes and nutrition status of iron, iodine, zinc, vitamins A and D, folate, vitamin B12, and riboflavin is presented. Nutrient-nutrient interactions of micronutrients, age, gender, and other host and environmental conditions, such as pregnancy, genetic conditions, overall nutrition, force of infection, and social conditions are considered as covariates in trying to define causation and outcomes due to specific micronutrients. The outcomes analyzed focus on growth and development, mental and neuromotor performance, immunocompetence, physical working capacity, morbidity, and in the case of pregnancy, overall reproductive performance. The results presented include responses to specific and multiple "experimental" interventions. A brief analysis of possible public health programs is presented, with emphasis on prevention.

Adolescent↗