Effect Of Zinc Intake Research Articles

Effect of zinc intake on association between fluoride exposure and abnormal sex steroid hormones among US pubertal males: NHANES, 2013-2016.

Excessive fluoride exposure can disturb the balance of sex hormones. Zinc is essential for sex hormone synthesis and spermatogenesis. But it is not clear how zinc affects the relationship of fluoride exposure with abnormal sex steroid hormones. Here, a total of 1008 pubertal males from the National Health and Nutrition Examination Survey (NHANES) in two cycles (2013-2014, 2015-2016) were enrolled. The concentrations of water fluoride and plasma fluoride and the levels of serum testosterone, estradiol, and sex hormone binding globulin (SHBG) were measured. Two 24-h dietary recall interviews were conducted to assess the dietary zinc intake. The relationships of fluoride exposure and zinc intake with sex hormones were examined using linear regression and logistic regression models, while the generalized additive model was used to evaluate their non-linear relationship. Our findings revealed that for every two-fold increase in plasma fluoride concentration, testosterone levels decreased by 7.27% (95% CI - 11.49%, - 2.86%) and estradiol levels decreased by 8.73% (95% CI - 13.61%, - 3.57%). There was also significant non-linear association observed between zinc intake and SHBG levels. Being in the first tertile of plasma fluoride had a 60% lower risk of high SHBG (OR = 0.40, 95% CI 0.18, 0.89) compared with being in the second tertile. When compared to the first tertile, being in the second tertile of zinc intake was associated with a 63% (OR = 0.37, 95% CI 0.14, 0.98) lower risk of high SHBG. Furthermore, we observed an interactive effect between the plasma fluoride and zinc intake on estradiol and SHBG, as well as the risk of high SHBG (P-interaction < 0.10). These findings suggest that fluoride exposure and zinc intake can affect sex steroid hormone levels and the risk of high SHBG. Notably, zinc intake may alleviate the increased risk of high SHBG and the abnormal changes of estradiol and SHBG caused by higher fluoride exposure.

Zinc Status is not Adversely Affected by Folic Acid Supplementation and Zinc Intake does not Impair Folate Utilization in Human Subjects

Changes in zinc status in response to folic acid supplementation and the effect of zinc intake on folate utilization were evaluated in 12 men (20–34 y old) consuming a diet containing 3.5 or 14.5 mg zinc/d for two 25-d intervals. Deuterium-labeled folic acid (800 μg/d) or a placebo was administered orally during each phase. No differences in plasma zinc, erythrocyte zinc, urinary zinc, erythrocyte metallothionein or serum alkaline phosphatase, due to supplemental folic acid, were detected at either level of zinc intake. Differences in the response to folic acid supplementation, due to the level of zinc intake, were not detected for serum, erythrocyte or urinary (labeled and unlabeled) folate. Within the constraints of this short-term folic acid supplementation study, adverse effects on zinc status were not observed and our data suggest that folic acid utilization was not influenced by level of zinc intake.

Association of zinc intake &amp; serum zinc levels with acne severity

96 Normal 0 false false false EN-US ZH-CN AR-SA Background: Recent studies have suggested the relationship between diet and acne, and zinc plays a role through its anti-inflammatory mechanism. This study aimed to determine the association between zinc intake and serum zinc levels with acne severity. Methods: A comparative cross-sectional study was conducted to assess the difference in zinc intake and serum zinc levels with acne severity based on Indonesian Acne Expert Meeting (IAEM) criteria. Sixty patients with acne in Dr. Cipto Mangunkusumo General Hospital were selected. The effect of zinc intake on acne severity was analyzed via unpaired T test, whereas the effect of serum zinc levels on acne severity was examined with Mann&ndash;Whitney test. Data were further evaluated using SPSS 20.0. Results: Zinc intake in all the subjects was below the Indonesian recommended daily allowance, and the mean of zinc intake and serum zinc levels in the mild acne group was higher than that of the moderate&ndash;severe acne group. The zinc intake significantly differed between the mild and moderate&ndash;severe acne groups (p &lt; 0.01). Likewise, serum zinc levels significantly varied between mild and moderate&ndash;severe acne group (p = 0.048). Conclusion: Although this study showed a significant difference between zinc intake and serum zinc levels with the severity of acne vulgaris, further follow-up studies should be performed to assess zinc for acne vulgaris therapy. Keywords: zinc intake, serum zinc level, acne severity

Effect of zinc intake on hepatic autophagy during acute alcohol intoxication.

Autophagy is a conserved mechanism that plays a housekeeping role by eliminating protein aggregates and damaged organelles. Recent studies have demonstrated that acute ethanol intoxication induces hepatic autophagy in mice. The effect of dietary zinc intake on hepatic autophagic flux during ethanol intoxication has not been evaluated using animal models. Herein, we investigated whether zinc deficiency and excess can affect autophagic flux in the liver in mice and in human hepatoma cells acutely exposed to ethanol. A mouse model of binge ethanol feeding was utilized to analyze the effect of low, adequate, and high zinc intake on hepatic autophagic flux during ethanol intoxication. Autophagic flux was inferred by analyzing LC3II/LC3I ratio, protein levels of p62/SQSTM1, Beclin1 and Atg7, and phosphorylation of 4EBP1. In addition, the degradation of the fusion protein LC3-GFP and the formation of autophagosomes and autolysosomes were evaluated in cells. Ethanol treatment stimulated autophagy in mice and cells. High zinc intake resulted in enhanced autophagy in mice exposed to ethanol. Conversely, zinc deficiency was consistently associated with impaired ethanol-induced autophagy in mice and cells. Zinc-deficient mice exhibited a high degree of ethanol-driven steatosis. Furthermore, zinc depletion increased apoptosis in cells exposed to ethanol. The results of this study suggest that adequate zinc intake is necessary for proper stimulation of autophagy by ethanol. Poor zinc status is commonly found among alcoholics and could likely contribute to faulty autophagy.

Zinc intake, status and indices of cognitive function in adults and children: a systematic review and meta-analysis.

In developing countries, deficiencies of micronutrients are thought to have a major impact on child development; however, a consensus on the specific relationship between dietary zinc intake and cognitive function remains elusive. The aim of this systematic review was to examine the relationship between zinc intake, status and indices of cognitive function in children and adults. A systematic literature search was conducted using EMBASE, MEDLINE and Cochrane Library databases from inception to March 2014. Included studies were those that supplied zinc as supplements or measured dietary zinc intake. A meta-analysis of the extracted data was performed where sufficient data were available. Of all of the potentially relevant papers, 18 studies met the inclusion criteria, 12 of which were randomised controlled trials (RCTs; 11 in children and 1 in adults) and 6 were observational studies (2 in children and 4 in adults). Nine of the 18 studies reported a positive association between zinc intake or status with one or more measure of cognitive function. Meta-analysis of data from the adult's studies was not possible because of limited number of studies. A meta-analysis of data from the six RCTs conducted in children revealed that there was no significant overall effect of zinc intake on any indices of cognitive function: intelligence, standard mean difference of <0.001 (95% confidence interval (CI) -0.12, 0.13) P=0.95; executive function, standard mean difference of 0.08 (95% CI, -0.06, 022) P=0.26; and motor skills standard mean difference of 0.11 (95% CI -0.17, 0.39) P=0.43. Heterogeneity in the study designs was a major limitation, hence only a small number (n=6) of studies could be included in the meta-analyses. Meta-analysis failed to show a significant effect of zinc supplementation on cognitive functioning in children though, taken as a whole, there were some small indicators of improvement on aspects of executive function and motor development following supplementation but high-quality RCTs are necessary to investigate this further.

Effect of Zinc Intake on Growth in Infants: A Meta-analysis

A systematic review and meta-analysis of available randomized controlled trials (RCTs) was conducted to evaluate the effect of zinc (Zn) intake on growth in infants. Out of 5500 studies identified through electronic searches and reference lists, 19 RCTs were selected after applying the exclusion/inclusion criteria. The influence of Zn intake on growth was considered in the overall meta-analysis. Other variables were also taken into account as possible effect modifiers: doses of Zn intake, intervention duration, nutritional status, and risk of bias. From each select growth study, final measures of weight, length, mid upper arm circumference (MUAC), head circumference, weight for age z-score (WAZ), length for age z-score (LAZ), and weight for length z-score (WLZ) were assessed. Pooled β and 95% confidence interval (CI) were calculated. Additionally, we carried out a sensitivity analysis. Zn intake was not associated with weight, length, MUAC, head circumference, and LAZ in the pooled analyses. However, Zn intake had a positive and statistically effect on WAZ (β = 0.06; 95%CI 0.02 to 0.10) and WLZ (β = 0.05; 95%CI 0.01 to 0.08). The dose–response relationship between Zn intake and these parameters indicated that a doubling of Zn intake increased WAZ and WLZ by approximately 4%. Substantial heterogeneity was present only in length analyses (I2 = 45%; p = 0.03). Zn intake was positively associated with length values at short time (four to 20 weeks) (β = 0.01; CI 95% 0 to 0.02) and at medium doses of Zn (4.1 to 8 mg/day) (β = 0.003; CI 95% 0 to 0.01). Nevertheless, the effect magnitude was small. Our results indicate that Zn intake increases growth parameters of infants. Nonetheless, interpretation of these results should be carefully considered.

Effect of zinc intake on mental and motor development in infants: a meta-analysis.

A systematic review and meta-analysis of available randomized controlled trials (RCTs) was conducted to evaluate the effect of zinc (Zn) intake on mental and motor development in infants. Out of 5500 studies identified through electronic searches and reference lists, 5 RCTs were selected after applying the exclusion/inclusion criteria. The influence of Zn intake on mental and motor development was considered in the overall meta-analysis. Other variables were also taken into account as possible effect modifiers: doses of Zn intake, intervention duration, nutritional situation, and risk of bias. Indices of mental and motor development assessed were the Mental Development Index (MDI) and Psychomotor Development Index (PDI). Additionally we carried out a sensitivity analysis. The pooled β was -0.01 (95 %CI -0.02, 0) for MDI and 0 (95 %CI -0.03, 0.02) for PDI, with a substantial heterogeneity in both analyses. When we performed a meta-regression, the effect of Zn supplementation on MDI changed depending on the dose of supplementation. Regarding PDI, there was a differential effect of Zn intake depending on intervention duration, dose of supplementation, nutritional situation, and risk of bias. Zn supplementation showed a negative, weak and significant effect on PDI score in those studies with a length of 4 to 20 weeks (β= -0.05; CI 95 % -0.06 to -0.04). In conclusion, no association was found between Zn intake and mental and motor development in infants. Further standardized research is urgently needed to clarify the role of Zn supplementation upon infant mental and motor development, particularly in Europe.

Effect of zinc intake on serum/plasma zinc status in infants: a meta-analysis.

A systematic review and meta-analysis of available randomised controlled trials (RCTs) was conducted to evaluate the effect of zinc (Zn) intake on serum/plasma Zn status in infants. Out of 5500 studies identified through electronic searches and reference lists, 13 RCTs were selected after applying the exclusion/inclusion criteria. The influence of Zn intake on serum/plasma Zn concentration was considered in the overall meta-analysis. Other variables were also taken into account as possible effect modifiers: doses of Zn intake, intervention duration, nutritional status and risk of bias. The pooled β of status was 0.09 [confidence interval (CI) 0.05 to 0.12]. However, a substantial heterogeneity was present in the analyses (I(2) = 98%; P = 0.00001). When we performed a meta-regression, the effect of Zn intake on serum/plasma Zn status changed depending on the duration of the intervention, the dose of supplementation and the nutritional situation (P ANCOVA = 0.054; <0.001 and <0.007, respectively). After stratifying the sample according to the effect modifiers, the results by duration of intervention showed a positive effect when Zn intake was provided during medium and long periods of time (4-20 weeks and >20 weeks). A positive effect was also seen when doses ranged from 8.1 to 12 mg day(-1). In all cases, the pooled β showed high evidence of heterogeneity. Zn supplementation increases serum/plasma Zn status in infants, although high evidence of heterogeneity was found. Further standardised research is urgently needed to reach evidence-based conclusions to clarify the role of Zn supplementation upon infant serum/plasma Zn status, particularly in Europe.

The relationship between zinc intake and indices of cognitive function: A systematic review and meta-analyses

.The databases searched included MEDLINE, EMBASE (both on Ovid) and the Cochrane Library CENTRAL from inception to March2013. Following the EURRECA protocol of screening and sorting, 2173 studies were assessed for eligibility criteria. Data was extractedfrom 19 studies across all population groups that met the inclusion and exclusion criteria (12 randomised controlled trials (RCTs), and7 observational studies). Meta-analysis of data extracted from 7 RCTs conducted in children was undertaken using Review Manager (5.2).A random effects model was used to investigate the impact of zinc intake on indices of cognitive function including intelligence (7 datasets from 862 children), executive function (7 data sets from a 942 children), and motor development (4 data sets from 622 children).The analysis yielded a pooled standard mean difference for the impact of zinc supplementation on intelligence of 0.06 (95% CI - 0.10,0.22) p = 0.47; executive function, 0.13 (95% CI, - 0.02, 029) p = 0.10 and motor development, - 0.05 (95% CI - 0.36, 0.26) p = 0.75.These results revealed that there was no signiÞcant overall effect of zinc supplementation on these cognitive function outcomes assessedin children.Due to the heterogeneity of the cognitive function test methodology, only a small number of studies could be included in the meta-analysis. To date, the evidence regarding the effect of zinc intake on cognitive function remains inconclusive. However, taking all thestudies per population as a whole there is some evidence for a positive association between zinc and cognitive function and there is a needfor further high quality RCTs to investigate this relationship.

Maternal zinc intake of Wistar rats has a protective effect in the alloxan-induced diabetic offspring

Zinc has a role in the synthesis, storage, and secretion of insulin, and has been suggested to be beneficial when used in the diabetic state. Effect of zinc intake in pregnant rats has been studied here on diabetized offspring. Pregnant rats were divided in two groups; the control group received normal food and water, and the experimental group received zinc sulfate during pregnancy and 3 weeks after offspring birth. Male offspring from the control (C) and experimental (E) groups were divided each in three groups: C1, fed with normal food and water; C2, diabetized with alloxan; C3, received zinc sulfate; E1, fed with normal food and water; E2, diabetized with alloxan; and E3, receiving zinc sulfate. After 30 days, the histological changes of pancreatic tissues were investigated by light microscopy. Body weight, blood glucose, serum insulin levels, food intake, water intake, and urine quantity were also compared between the groups. Water intake and urine quantity were decreased significantly (p < 0.01 and p < 0.001) in E2 (experimental diabetic group) in comparison with C2 (control diabetic group), but there was no significant difference in the body weight in C2 in comparison with E2, while blood glucose was decreased significantly (p < 0.001) and blood insulin level was increased significantly (p < 0.01) in E2 in comparison with C2. Microscopic evaluation of pancreas showed that E2 were protected against alloxan-induced beta-cell degeneration. In conclusion, this work showed that maternal zinc intake may influence subsequent deleterious effects of diabetes on alloxan-diabetized offspring.

Effect of dietary zinc on 65-ZN absorption and turnover in rats

The effect of zinc intake on retention, absorption, and biological half-life of 65-Zn was investigated using whole body counting after the carrier-free radioisotope was administered intragastrically or intramuscularly to 7-week old male rats. When animals consumed 7.8, 11.7, 16.0, 20.8, 36.8, 80.2, or 149.1 mg Zn/kg diet for 3 weeks before and 4 weeks after 65-Zn administration, the biological half-life and the retention of gavaged or injected 65-Zn were curvilinearly related to the dietary zinc concentration. Absorption was similarly affected, except that absorption was nearly 100 per cent at the two lowest levels of intake. Zinc concentrations in bone and serum were unaffected except in animals fed 7.8 mg Zn/kg diet. When zinc intakes varied only 4 days before 65-Zn administration, retention of injected 65-Zn and absorption were less affected. Animals fed 11.5 rather than 85.0 mg Zn/kg beginning 7 to 8 hours after 65-Zn administration, had greater retention of gavaged or injected 65-Zn; absorption and biological half-life of 65-Zn were also greater. Thus, retention of dietary zinc by the body depended on recent and subsequent zinc intake, with recent intake affecting mainly absorption, and subsequent intake affecting mainly excretion. Adjustments in absorption and excretion occurred within days, and were highly coordinated when zinc intakes exceeded the requirement.

Effect of zinc intake on copper excretion and retention in men

To determine the influence of zinc intake on copper excretion and retention, nine men consumed diets containing 2.6 mg of copper/day and 1.8, 4.0, 6.0, 8.0, 18.5 or 20.7 mg of zinc/day for one- or two-week periods in a 63-day study. Copper and zinc in the diet and copper in plasma were determined weekly; fecal copper was determined daily and averaged within each week. The weekly mean (+/-SEM) plasma copper concentrations (81 +/- 3.3 to 100 +/- 5.8 micrograms/dl) remained within the normal range throughout the study. Fecal copper and apparent copper retention were influenced by the level of dietary zinc and the duration it was fed. When 18.5 mg of zinc/day was fed for two consecutive weeks following a lower zinc intake, fecal copper was elevated and apparent copper retention was reduced after a one-week lag. Thus, an intake of zinc only 3.5 mg/day above the RDA for men reduced apparent retention of copper at an intake of 2.6 mg/day.

Effects of zinc intake on copper balance in adult females

Adult women were fed dietary regimens that provided 2.0 mg of copper and either 8, 16, 24, mg of zinc daily in a 18-day controlled metabolic study. Zinc retentions were positive at all levels of intake, but the lowest level was probably not sufficient to maintain equilibrium. An intake of 16 mg of zinc was sufficient to maintain subjects in positive balance or at equilibrium, although this level may be marginal for individuals living in warm climates with potentially large sweat losses. None of the dietary groups was in positive balance on a copper intake of 2 mg/day, although the dietary level of zinc had no effect on copper retentions. Serum levels of copper decreased and zinc increased during the study.

The relationship of zinc to protein utilization in the preadolescent child

The effects of zinc intake on nitrogen utilization was investigated during a 20-day balance study with 23 preadolescent girls. The children were fed a diet which provided 4.17 g of nitrogen and 5.5 mg of zinc daily; the diet was supplemented with a combination of 5 mg of zinc and/or nitrogen supplied from either amino acids or nonspecific nitrogen. Complete collections of excreta were made throughout the study. Neither the supplementation of amino acids nor zinc improved the retention of nitrogen. Urinary excretion of urea nitrogen, uric acid, and creatinine were not different as a result of zinc supplementation. Subjects consuming the lower level of zinc were in negative zinc balance, but the subjects consuming 10.5 mg of zinc were in positive balance. The supplementation of this low protein diet with amino acids did not improve nitrogen retention.