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PubMed2000

Assessment of macronutrient and micronutrient intake in women with anorexia nervosa.

OBJECTIVE: The purpose of this study is to evaluate the accuracy of diet history compared to observed food intake in the nutritional assessment of women with anorexia nervosa (AN) and healthy age-matched controls. METHOD: One-month diet history was compared to 1-day observed food intake in 30 women with AN and 28 control subjects. RESULTS: Reported intake by diet history was similar to observed intake for macronutrient composition and fat intake for patients with AN. Reported energy intake was higher than observed intake (1,602 +/- 200 kcal vs. 1,289 +/- 150 kcal, p <.05), but was in agreement with predicted energy expenditure by the Harris-Benedict equation (1,594 +/- 18 kcal, p =.97) in patients with AN. Micronutrient intake by diet history was highly correlated with observed intake in patients with AN. More than one half of the patients with AN failed to meet the recommended dietary allowance (RDA) for vitamin D, calcium, folate, vitamin B12, zinc, magnesium, and copper when assessed by diet history. In contrast to patients with AN, diet history did not correlate with observed intake of energy, macronutrients, or most micronutrients among the controls. DISCUSSION: Diet history is an accurate tool to assess fat intake and macronutrient composition in patients with AN and demonstrates significant micronutrient deficiencies in this population. The agreement between total energy intake and predicted energy expenditure supports the overall utility of the diet history in the nutritional assessment of patients with AN.

Adolescent↗
PubMed1989

Selected indices of micronutrient status in adult patients with sickle cell anemia (SCA).

In 24 adults with hemoglobin SS followed at the Duke University Comprehensive Sickle Cell Center, we have studied the following nutritional parameters: reduced ascorbic acid; dehydroascorbic acid; alpha and beta carotenes; cryptoxanthin; and alpha and gamma tocopherols in whole blood, washed red blood cells, plasma, or serum. In the same population we also examined reduced glutathione (GSH) and oxidized glutathione (GSSG). Fifteen of these 24 patients also were interviewed for usual dietary intakes using a 28-day dietary history. Data obtained from patients with hemoglobin SS, sickle cell anemia (SCA) were compared to those found for seven healthy normal black adults of similar age. Plasma alpha tocopherol levels were significantly lower in SCA individuals than those of the controls (P less than 0.004). Alpha and gamma tocopherol levels in sickle RBCs were significantly higher than those from RBC suspensions of control subjects (P less than 0.007, and P less than 0.001, respectively). All serum values for carotenoids examined, specifically, beta carotene, alpha carotene, and cryptoxanthin were also markedly depressed when compared to those of healthy controls (P less than 0.001, P less than 0.002, and P less than 0.001, respectively). No other statistically significant differences were found between the two groups for any of the remaining variables, including dietary estimates. Dietary analyses suggest that dietary intakes of SCA individuals exceeded the recommended daily allowances (RDA) of all macro- and micronutrients measured, and intakes of most nutrients exceeded those of black controls interviewed. These results suggest that in individuals with SCA, several micronutrients vital to maintaining reducing capacity are present in diminished quantities in plasma/serum. These anomalies exist in SCA patients even though their intake of these micronutrients are similar to those of healthy black men and women.

Adult↗
PubMedDate not supplied

Micronutrients and tropical infections.

There is now considerable evidence for bidirectional interactions between micronutrients and tropical infections but it is clear that research to date has only touched the surface of the problem and much remains to be learned at both the basic science and public health levels. Much research has been directed towards iron and there is increasing interest in zinc and vitamin A, but other micronutrients have been largely ignored. The few available studies on antioxidants suggest that these nutrients may also have important effects on tropical infections and further research is warranted. In addition, there is a need for information on appropriate methods of assessing status of particular micronutrients during infection, which is often endemic in populations likely to be deficient, in order to improve interpretation of research results and provide a more secure basis for any clinical or public health supplementation programmes.

Humans↗
PubMed1993

Oral cancer inhibition by micronutrients. The experimental basis for clinical trials.

Extensive research has been carried out in experimental animals to demonstrate the anticancer activity of retinoids, carotenoids and tocopherol on oral cancer and oral precancerous leukoplakia. The anticancer properties of these micronutrients have been studied in experiments dealing with inhibition of carcinogenesis, prevention of oral cancer development and regression of established oral carcinoma. Synergism has been demonstrated in the anticancer activity of beta carotene and alpha tocopherol. Synergism has also been demonstrated between beta carotene and anticancer alkylating agents such as melphalan and cyclophosphamide. Micronutrients such as beta carotene have been found to inhibit both major phases of carcinogenesis--initiation and promotion. Animal studies of oral cancer inhibition, prevention and regression have been substantiated by tissue culture studies, using animal and human derived oral cancer cell lines and normal epithelial cells. Mechanisms of the anticancer activity of the micronutrients on experimental oral cancer have been explored. They include stimulation of elements of the immune system to kill cancer cells, and enhanced expression of heat-shock proteins and repressor genes such as P 53.

Animals↗
PubMed1996

Update on the biological characteristics of the antioxidant micronutrients: vitamin C, vitamin E, and the carotenoids.

Under normal circumstances, free radicals that are produced through biological processes and in response to exogenous stimuli are controlled by various enzymes and antioxidants in the body. Laboratory evidence suggests that oxidative stress, which occurs when free radical formation exceeds the ability to protect against them, may form the biological basis of several acute medical problems, such as tissue injury after trauma, and chronic conditions, such as atherosclerosis and cancer. A potential role for the antioxidant micronutrients (vitamin C, vitamin E, and the carotenoids) in modifying the risk for conditions that may result from oxidative stress has stimulated intense research efforts, increased interest in micronutrient supplements, and heightened consumer interest in these compounds. Much remains to be learned, however, about the bioavailability, tissue uptake, metabolism, and biological activities of these micronutrients. These biological characteristics will ultimately determine their clinical usefulness in modulating oxidative stress. Also, whether the antioxidant mechanism explains their relationship with risk for acute and chronic disease in epidemiologic studies remains to be determined. Increased knowledge in this area of nutrition science will have an impact on both clinical dietetics practice and public health nutrition guidelines.

Animals↗
PubMed1999

Role of micronutrients in activated sludge-based biotreatment of industrial effluents.

Industrial processes often produce wastewaters that resist biological treatment owing to the unfamiliarity of some components to biological systems. Availability of nutrients determines the community structure of the activated sludge and hence the efficiency of the degradation process. Micronutrients influence the bacteria involved in waste degradation and also the species diversity within the sludge. The requirements for and toxicity of different micronutrients vary according to the nature of the waste and the ecology of the sludge. Adding micronutrients to biological treatment processes is one possible approach to upgrading an existing facility in order to deal with increasing volumes and strengths of industrial wastewaters and the tightening discharge legislation.

Journal Article↗
PubMed2007

Andean potato cultivars (Solanum tuberosum L.) as a source of antioxidant and mineral micronutrients.

Potato tubers were evaluated as a source of antioxidants and minerals for the human diet. A genetically diverse sample of Solanum tuberosum L. cultivars native to the Andes of South America was obtained from a collection of nearly 1000 genotypes using microsatellite markers. This size-manageable collection of 74 landraces, representing at best the genetic diversity among potato germplasm, was analyzed for iron, zinc, calcium, total phenolic, total carotenoid, and total vitamin C contents. The hydrophilic antioxidant capacity of each genotype was also measured using the oxygen radical absorbance capacity (ORAC) assay. The iron content ranged from 29.87 to 157.96 microg g-1 of dry weight (DW), the zinc content from 12.6 to 28.83 microg g-1 of DW, and the calcium content from 271.09 to 1092.93 microg g-1 of DW. Total phenolic content varied between 1.12 and 12.37 mg of gallic acid equiv g-1 of DW, total carotenoid content between 2.83 and 36.21 microg g-1 of DW, and total vitamin C content between 217.70 and 689.47 microg g-1 of DW. The range of hydrophilic ORAC values was 28.25-250.67 micromol of Trolox equiv g-1 of DW. The hydrophilic antioxidant capacity and the total phenolic content were highly and positively correlated (r = 0.91). A strong relationship between iron and calcium contents was also found (r = 0.67). Principal component analysis on the studied nutritional contents of the core collection revealed that most potato genotypes were balanced in terms of antioxidant and mineral contents, but some of them could be distinguished by their high level in distinct micronutrients. Correlations between the micronutrient contents observed in the sample and the genetic distances assessed by microsatellites were weakly significant. However, this study demonstrated the wide variability of health-promoting micronutrient levels within the native potato germplasm as well as the significant contribution that distinct potato tubers may impart to the intake in dietary antioxidants, zinc, and iron.

Antioxidants↗
PubMed1993

Micronutrients in gastrointestinal cancer.

The monitoring of micronutrients and the relationship between dietary intake and micronutrient status prior to and after surgery in patients with histologically proven gastrointestinal adenocarcinoma, both weight-stable and weight-losing (> 7.5% of their pre-illness weight) has been studied and the results compared to controls. Plasma vitamin C and red blood cell thiamine levels were significantly lower in weight-losing cancer patients when compared to their weight-stable counterparts (P < 0.05 and P < 0.02 respectively). Weight-losing patients had a lower vitamin C (P < 0.05) and thiamine (P < 0.002) intake, and a higher elevation in plasma C-reactive protein and a lower prealbumin level (P < 0.02), when compared to both weight-stable cancer patients and controls. Plasma vitamin C, prealbumin and C-reactive protein levels remained unchanged after curative resections of the tumours compared to a preoperative value, and there was a highly significant correlation between plasma vitamin C and dietary intake of vitamin C. This study suggests that the lower vitamin C and thiamine status in weight-losing gastrointestinal cancer patients prior to surgery is due to a lower micronutrient intake and an acute phase response to their illness. Dietary intake of vitamin C appears to be the major factor in determining plasma vitamin C concentration following curative surgical resection.

Adenocarcinoma↗
PubMed1998

Plasma concentrations of micronutrients during a nine-month clinical trial of beta-carotene in women with precursor cervical cancer lesions.

The effects of oral supplementation of a 30-mg dose of beta-carotene on the plasma levels of carotenoids, tocopherols, and retinol were studied sequentially in 69 patients participating in a nine-month randomized placebo controlled trial conducted to examine efficacy of beta-carotene to induce regression of cervical intraepithelial neoplasia. At each visit (baseline and 1.5, 3, 6, 9, 10.5, and 15 mo), blood samples were collected and the levels of six micronutrients were determined by high-performance liquid chromatography. No limitations or changes were introduced in each participant's dietary habits. Cervico-vaginal lavage samples were also obtained at the same visit and assayed for the presence of human papillomavirus DNA by Southern blot hybridization and polymerase chain reaction. In the supplemented group, mean plasma beta-carotene levels were significantly higher (p = 0.0001) than baseline and remained markedly elevated for 15 months. In the longitudinal analysis of the placebo group, there were no variations among individual mean plasma levels of beta-carotene, alpha-carotene, lycopene, retinol, gamma-tocopherol, or alpha-tocopherol, suggesting absence of seasonal or dietary changes. In the placebo group, cigarette smoking and steroid contraceptive use were significantly associated with low levels of plasma beta-carotene (p = 0.05 and p = 0.012, respectively). However, in contrast, in the beta-carotene-supplemented group, steroid contraceptive use had no influence on the plasma beta-carotene levels. An additional noteworthy finding was that beta-carotene supplementation did not reverse the depletion effect in smokers. There was no association between the plasma levels of these six micronutrients in women with cervical intraepithelial neoplasia and persistent human papillomavirus infection status in the placebo or the supplemented groups. Functional sequential nutrient interactions with each other or with other essential micronutrients and possible long-term toxicity need to be addressed in clinical trials.

Adult↗
PubMed1992

Effect of interleukin-2 on some micronutrients during adoptive immunotherapy for various cancers.

In 20 patients, we investigated the effect of interleukin-2 (IL-2) treatment during adoptive immunotherapy for various cancers on circulating levels of: thiamin; biotin; folate; pantothenate; riboflavin; nicotinate; vitamins A, B6, B12 and E; carotenes; free and total cholines; inositol; and free and total carnitines. Of the above micronutrients, only vitamins A, B6, B12, inositol, carotenes and folate varied markedly from normal levels (pre IL-2 exposure) to abnormal levels (post IL-2). Following IL-2 exposure, every patient's B12 level was significantly elevated; 50% of the levels were abnormally increased above 1000 pg/ml. Extreme significant elevations of inositol were also seen in 90% of the patients. In contrast, IL-2 exposure depressed normal vitamins A, B6, carotene, and folate levels to subnormal; 90% of the patients became B6 hypovitaminemic; 60% for vitamin A, 80% for carotene, and 45% for folate. Other micronutrients tested showed no clear deviations from normal levels post IL-2 exposure. Some reasons for micronutrient variations are discussed.

Adult↗
PubMed1993

Antioxidant micronutrients and breast cancer.

We reviewed epidemiologic evidence on the relationship between four antioxidant micronutrients (vitamin A, vitamin C, vitamin E, and selenium) and breast cancer risk. Available data support a modest protective effect of vitamin A, although more studies are needed to examine further this association and to assess the relative contributions of preformed vitamin A (retinol) and carotenoids. In addition, the possibility that some other component of vitamin A-rich foods may account for this observed association should be explored. Data on the relationship between vitamins C and E and breast cancer risk are limited and inconsistent, and further information is necessary. A substantial body of evidence indicates a lack of any appreciable effect of selenium intake on breast cancer risk, at least within the range of human diets. Future observational studies should ideally be prospective in design, as prospective studies are less prone to selection and recall bias than are case-control studies, and should address methodologic issues such as confounding by other micronutrients and appropriate storage conditions of blood specimens. Although hypotheses relating micronutrient intake to risk of breast cancer should be tested in randomized trials, ethical and logistical constraints make these studies difficult to perform.

Antioxidants↗
PubMed1987

Micronutrient status in diabetes mellitus.

Diabetes mellitus is a chronic metabolic disorder, which can alter the nutritional status of the individual. Some micronutrients, in particular zinc and chromium, have been implicated in the pathogenesis of carbohydrate intolerance. This review evaluates the available published data on the status of 10 mineral elements and seven vitamins in diabetic patients and experimental animal models of diabetes. The role of these micronutrients in insulin secretion and carbohydrate metabolism is discussed in an attempt to determine whether the reported alterations in serum or tissue content of minerals or vitamins contribute to the carbohydrate intolerance of diabetic patients. It is concluded that both Type I and Type II diabetes mellitus can result in changes in certain micronutrients. However, adequately controlled studies to establish the role of trace elements in the pathogenesis of diabetes mellitus are not available.

Bone Diseases, Metabolic↗
PubMed1992

Factors related to the plasma fatty acid profile in healthy subjects, with special reference to antioxidant micronutrient status: a multivariate analysis.

The plasma lipid fatty acid (FA) profile was measured in 83 healthy subjects (35 men, 48 women; ages 18-82 y). The association of 19 variables (including serum antioxidant micronutrients) with saturated (SFA), monounsaturated (MUFA), essential (EFA), and polyunsaturated fatty acid (PUFA) status was assessed by stepwise multiple-linear regression. Serum selenium was directly associated with percent EFA and n-6 PUFA (r = 0.38, P = 0.0004 for both) and inversely related to percent SFA in phospholipids (r = -0.38, P = 0.0004). Serum selenium was the only predictor of the unsaturation index of this fraction (r = 0.45, P = 0.0000). Although associations of plasma FA pattern with age, serum cholesterol, bilirubin, vitamin E, and zinc were also disclosed, only for selenium did the antioxidant effect seem to explain this relationship. These results suggest that antioxidant micronutrients should be measured when PUFA metabolism is studied. The relationship between plasma FA and antioxidant micronutrients in disease states needs further research.

Adolescent↗
PubMed1998

Effects of repletion with zinc and other micronutrients on neuropsychologic performance and growth of Chinese children.

The knowledge that zinc is essential for growth and neuropsychologic performance and a report of zinc-responsive stunting in Chinese children prompted this project. This article summarizes findings from a 10-wk, double-blind, controlled trial of zinc repletion in 740 urban, 6-9-y-old first graders from low-income families in Chongqing, Qingdao, and Shanghai, People's Republic of China. Treatments were 20 mg Zn alone (Z), 20 mg Zn with micronutrients (ZM), and micronutrients alone (M). The M mixture was based on National Research Council guidelines. Nutrients that might interfere with zinc retention were excluded or given in lower amounts. Main outcomes were changes in neuropsychologic performance and knee height. Hemoglobin, serum ferritin, plasma and hair zinc, and whole blood and hair lead were also measured. Anemia was not common, and serum ferritin concentrations were usually within the range of normal. Mean baseline plasma zinc concentrations were marginal in children from Chongqing and Qingdao and normal in children from Shanghai. After treatment with ZM or M plasma zinc increased. Hair zinc tended to decrease after all treatments. Mean baseline whole blood lead concentrations were slightly below the limit considered excessive for children by the US Centers for Disease Control and Prevention. Neuropsychologic performance and growth were most improved after treatment with ZM. These findings were consistent with the presence of zinc and other micronutrient deficiencies.

Brain↗
PubMed2003

Anaemia and micronutrient deficiencies.

Anaemia in pregnancy is a common and worldwide problem that deserves more attention. For many developing countries, prevalence rates of up to 75% are reported. Anaemia is frequently severe in these situations and can be expected to contribute significantly to maternal mortality and morbidity. After a discussion of definitions, screening for anaemia and prevalence, the relationship between anaemia and maternal mortality and morbidity will be reviewed. Micronutrient deficiency and especially iron deficiency is believed to be the main underlying cause for anaemia. More recently the role of vitamin A deficiency as a contributing factor to anaemia has also been examined. The difficulties of assessment of micronutrient sufficiency or deficiency in pregnancy are described, as is the interaction between infection and micronutrient deficiency states.

Anemia, Iron-Deficiency↗
PubMed2001

Intake of micronutrient-rich foods in rural Indian mothers is associated with the size of their babies at birth: Pune Maternal Nutrition Study.

One third of the Indian babies are of low birth weight (<2.5 kg), and this is attributed to maternal undernutrition. We therefore examined the relationship between maternal nutrition and birth size in a prospective study of 797 rural Indian women, focusing on macronutrient intakes, dietary quality and micronutrient status. Maternal intakes (24-h recall and food frequency questionnaire) and erythrocyte folate, serum ferritin and vitamin C concentrations were measured at 18 +/- 2 and 28 +/- 2 wk gestation. Mothers were short (151.9 +/- 5.1 cm) and underweight (41.7 +/- 5.1 kg) and had low energy and protein intakes at 18 wk (7.4 +/- 2.1 MJ and 45.4 +/- 14.1 g) and 28 wk (7.0 +/- 2.0 MJ and 43.5 +/- 13.5 g) of gestation. Mean birth weight and length of term babies were also low (2665 +/- 358 g and 47.8 +/- 2.0 cm, respectively). Energy and protein intakes were not associated with birth size, but higher fat intake at wk 18 was associated with neonatal length (P < 0.001), birth weight (P < 0.05) and triceps skinfold thickness (P < 0.05) when adjusted for sex, parity and gestation. However, birth size was strongly associated with the consumption of milk at wk 18 (P < 0.05) and of green leafy vegetables (P < 0.001) and fruits (P < 0.01) at wk 28 of gestation even after adjustment for potentially confounding variables. Erythrocyte folate at 28 wk gestation was positively associated with birth weight (P < 0.001). The lack of association between size at birth and maternal energy and protein intake but strong associations with folate status and with intakes of foods rich in micronutrients suggest that micronutrients may be important limiting factors for fetal growth in this undernourished community.

Adolescent↗
PubMed1992

Micronutrient distribution in 16-year-old maritime pine.

Concentrations and contents of the micronutrients Fe, Mn, Zn, Cu, and B were measured in various tree compartments of a 16-year-old stand of maritime pine (Pinus pinaster Soland in Ait.). The micronutrients were actively redistributed within the tree. The longer-lived aerial tissues, trunks and branches, constituted the major micronutrient reservoirs, with the exception of manganese which accumulated in the needles.

Journal Article↗
PubMed1983

Concentrations and total daily output of micronutrients in breast milk of mothers delivering preterm: a longitudinal study.

The number of preterm infants fed their own mother's milk appears to be increasing as a result of information suggesting certain benefits over milk from human milk banks or proprietary formulas. It is also apparent that the nutritional requirements of term and preterm infants differ. Thus, the finding of various deficiencies in small preterm infants indicates that studies which examine the nutrient content of milk from mothers who deliver prematurely are important to aid in suggesting appropriate supplementation. In order to provide appropriate recommendations, nutrient content must be assayed during the period of exclusive milk feedings. Accordingly, the concentrations and total daily output of breast milk zinc and copper, and vitamins A, C, and E, were examined in a group of 13 mothers delivering at or before 32 weeks gestation. Collections of a total 24-h output were obtained every 7 days for the first 7 weeks after delivery. Concentrations of all micronutrients were similar to those reported previously during the first 5 weeks of lactation. Most striking, however, was the progressive decline in total output as well as concentration of zinc. After the first 2 weeks of lactation, levels of copper and vitamins A, C, and E were not affected by the duration of lactation. There was substantial variation between mothers in daily output of all the micronutrients. The low output of these micronutrients suggests that some attempt should be made at monitoring the mineral and vitamin status of small preterm infants fed exclusively human milk for the first 3 months of life.(ABSTRACT TRUNCATED AT 250 WORDS)

Ascorbic Acid↗