Hair Zinc Research Articles

Interaction between Cadmium and Zinc Levels in the Biological Samples of Type 1 Diabetic Mellitus Children, Reside in Different Areas of Sindh, Pakistan

Type 1 Diabetes mellitus (T1DM) is one of the familiar childhood immune-mediated onsets and can lead to early mortalities and morbidities. It can arise at any stage, but the peak of occurrence is reported less than 18 years of age. T1DM cases in Pakistan were less than 2% of the total diabetic population. The current work designed to assess the concentration of cadmium (Cd) and zinc (Zn) in blood, scalp hair and serum samples of T1DM children, age ranged 1 - 14 years of both genders. For comparison purpose, the age-matched referent subjects of both genders were tested. The microwave-assisted acid digestion procedure was used to determine the elemental analysis in the biological samples of T1DM children and referent subjects. The resulted data of certified reference material of blood, scalp hair, and serum validated the certainty of the designed method. The analysis of Zn was performed by flame atomic absorption spectrometry, while the Cd contents were determined by electrothermal atomic absorption spectrometry. T1DM affected children of both genders have lower Zn level in the blood, scalp hair, and serum samples. Whereas, the levels of Cd were found to be higher in the biological samples of T1DM affected children as compared to referent subjects. The finding of the current study is a significant hypothesis for medical experts, to diagnose the deficiency of essential (Zn) and toxicity of heavy/toxic element (Cd) in the biological specimen of T1DM affected children.

Chromium Manganese and Zinc Levels in the Biological Samples of Type 1 Diabetic Mellitus Children Reside in Different Areas of Sindh Pakistan

T1DM is the most acquainted childhood immune-caused onset and may lead to early mortalities and morbidities. It can emanate in any age group but is highest reported in lesser than 18 years of age. In Pakistan only, T1DM institutes ~ 2% of the all diabetic population. This work was formulated to assess the concentration of manganese (Mn), zinc (Zn) and chromium (Cr) in blood, scalp hair and serum samples of diabetic mellitus type 1 children age ranged (1–5), (6-10) and (11-14) years of both genders (male and female), compared with similar sex and age referent subjects. For sample pretreatment, microwave-aided acid digestion procedure (MAD) was employed for elemental analysis in the biological samples of T1DM children. The employed method was validated by using certified reference samples of blood, scalp hair, and serum. Digests biological specimen were analyzed by AAS. The Zn was analyzed by FAAS, while the assessment of Mn and Cr were measured by ETAAS. The Mn, Zn and Cr, presents significantly low levels in the samples of scalp hair, blood and serum of female and male of age group of (1-5) (6-10) and (11-14) of diabetic mellitus type 1 children, compared with referent subjects. These data present an important hypothesis to doctors and other clinical experts to investigate insufficiency of these essential micronutrients (Cr, Mn, andamp; Zn) in biological specimen of blood, scalp hairs and serum of T1DM children.

Succeeding in deactivating: associations of hair zinc levels with functional and structural neural mechanisms

Zinc is a biologically essential element and involved in a wide range of cellular processes. Here, we investigated the associations of zinc levels in hair with brain activity during the n-back working memory task using functional magnetic resonance imaging, fractional anisotropy (FA) of diffusion tensor imaging, and cognitive differences in a study cohort of 924 healthy young adults. Our findings showed that greater hair zinc levels were associated with lower brain activity during working memory in extensive areas in the default mode network (i.e., greater task-induced deactivation) as well as greater FA in white matter areas near the hippocampus and posterior limbs of the internal capsule. These findings advance previous non-neuroimaging findings of zinc’s associations with excitability, excitability-associated disorders, and myelination.

Micronutrient deficiency in men with infertility

The study objective is to compare the level of micronutrients in men with infertility and men with normal fertility. Materials and methods. The levels of А, В9, D, Е, С vitamins in blood using high-performance liquid chromatography and selenium and zinc in hair using atomic absorption mass-spectrometry were measured in men with diagnosis of male idiopathic infertility (n = 82) and men with normal fertility (n = 93).Conclusion. Absence of a total lack of micronutrient deficiency in men with infertility was observed. Presumably, azoospermia can be associated with deficiency in some micronutrients casting doubt on the necessity of administration of multicomponent vitamin and mineral complexes.Results. Blood levels of А, D and В9 vitamins did not significantly differ in the studied groups, while differences in blood levels of С and Е vitamins and selenium and zinc in hair were statistically significant. While the levels of А, Е, В9 vitamins, selenium and zinc were in the reference ranges, vitamin C deficiency was observed in the test group and vitamin D deficiency in both groups. Higher level of selenium in the test group presumably reflects its higher metabolism due to higher influx of xenobiotics in the organism and indicates pre-deficiency state.

Апробация технологии выявления и коррекции элементозов молочных коров по элементному составу шерсти

Abstract. The study is aimed at assessing the effectiveness of a new technology for the diagnosis and correction of dairy cattle elementoses according to the chemical composition of hair, using elementoses of various etiologies. Methodology and methods. The experimental design included two studies: the first is a micropopulation of the Simmental cows with a deficiency of calcium, zinc, selenium and manganese in hair; the second is Black Spotted cows with a significant excess in the established standards for lead and cadmium against the background of a deficiency of calcium, zinc, selenium and copper. Based on a comparison of data after initial analysis of hair according to 25 parameters with physiological norm intervals a mineral premix consisting of organic forms of limited chemical elements was included in the diet for animals in the first and second experiments. In order to optimize lead and cadmium pools, sorbent of heavy metals was additionally included in the diets of experimental animals in the second experiment. Results and practical relevance. Feeding with corrective additives in the diets led to the normalization of elemental status for the vast majority of elements in both experiments. Moreover, cows in the first experiment had an increase in the yield of milk and milk fat by 7.2 % during the lactation period; in the second experiment, an increase in the number of fruitful inseminations was registered, it was accompanied by a decrease of calving interval and service periods by 4.5 and 17.7 %, with an increase in the calf yield. Scientific novelty. For the first time, the elemental profile of dairy cattle was described using distiller’s grain in feeding; the technology for identifying and correction of dairy cattle elementoses based on data of hair elemental composition has been developed in production conditions.

Selenium, Zinc, Chromium, and Vanadium Levels in Serum, Hair, and Urine Samples of Obese Adults Assessed by Inductively Coupled Plasma Mass Spectrometry.

The objective of this study was to investigate of selenium (Se), zinc (Zn), chromium (Cr), and vanadium (V) levels in blood serum, hair, and urine of adult obese patients. A total of 199 lean and 196 obese subjects were enrolled in the study. Serum, hair, and urinary metal and metalloid analysis were performed by inductively coupled plasma mass spectrometry at NexION 300D (PerkinElmer Inc., USA). The results established that obese subjects were characterized by 47% and 30% lower serum Cr and V levels compared with controls, respectively, whereas serum Se levels exceeded control values by 9%. In contrast, hair Cr, Se, and V content in obese subjects exceeded the control values by 51%, 21%, and 50%, respectively. In turn, hair Zn levels were found to be significantly lower by 11% compared with the lean control values. In urine, the levels of V and Zn were found to be 30% and 18% higher in obese patients. Prevalence of hypertension in obese subjects was associated with a trend for impaired Se and Zn levels. In a regression model adjusted for age, gender, hypertension, atherosclerosis, and glucose intolerance, serum Cr, V, and hair Zn were inversely associated with body mass index (BMI), whereas hair Se was considered as the positive predictor. Our data allow proposing that the observed alterations may at least partially contribute to metabolic disturbances in obesity. In turn, monitoring of Se exposure in a well-nourished adult population is required to reduce its potential contribution to obesity.

Plasma and Nail Zinc Concentrations, But Not Hair Zinc, Respond Positively to Two Different Forms of Preventive Zinc Supplementation in Young Laotian Children: a Randomized Controlled Trial

Plasma zinc concentrations (PZC) have been shown to significantly increase during zinc supplementation. This study investigated the effects of daily preventive zinc supplementation on hair and nail zinc concentrations compared with a control group. In a randomized controlled trial, 6- to 23-month-old children (n = 3407) in Lao PDR were randomly assigned to one of four groups and followed for ~ 36 weeks: daily preventive zinc dispersible tablet (7 mg/d; PZ), daily micronutrient powder (10 mg zinc/d; MNP), therapeutic zinc supplements for diarrhea treatment (20 mg/d for 10 days; TZ), or daily placebo powder (Control). Plasma, hair, and nail zinc concentrations were assessed in a sub-sample of participants (n = 457) at baseline and endline. At baseline, 75% of children had low PZC (< 65 μg/dL). At endline, geometric mean (95% CI) PZC were greater in the PZ and MNP groups compared with the TZ and control groups (P < 0.01), but hair zinc concentrations did not differ among groups (P = 0.99). Nail zinc concentrations were marginally higher in the PZ (115.8 (111.6, 119.9) μg/g) and the MNP (117.8 (113.3, 122.3) μg/g) groups than in the TZ group (110.4 (106.0, 114.8) μg/g; P = 0.055) at endline. This study does not support the use of hair zinc as a biomarker of zinc exposure in young children. However, it provides some evidence that zinc concentrations in nails may respond to supplemental zinc interventions and supports the need for collecting additional data on this emerging biomarker.

Investigating hair zinc concentrations in children with and without atopic dermatitis.

Atopic dermatitis (AD) is a common chronic inflammatory skin condition that disproportionately affects children and is associated with reduced quality of life. Zinc deficiency may contribute to the pathogenesis of AD because zinc plays a role in epidermal barrier integrity and the immune system. Systematic review evidence suggests that low zinc is associated with AD, but limitations of included studies support further investigation. To investigate hair zinc concentrations in children with AD v. healthy controls in a low- to middle-income country setting. One hundred and five children aged 1 - 12 yea-rs participated in a frequency-matched for age case-control study. The outcome variable, AD, was confirmed by a clinician and corroborated using the UK Working Party criteria. The primary predictor, long-term average zinc concentration, was determined by measuring hair zinc using inductively coupled mass spectrometry. Baseline demographic characteristics, anthropometry and measures of socioeconomic status were included in our logistic regression analysis. Subgroup analysis was performed where interaction terms suggested effect modification. Using data from the overall sample, population median hair zinc was not significantly different between children with AD and healthy controls. However, subgroup analysis suggested a clinically and statistically significant difference in median zinc between children with AD (175.35 µg/g) and healthy controls (206.4 µg/g) in the older age group (5 - 12 years) (p=0.01). In this age group, multivariable logistic regression analysis also found significantly decreased hair zinc concentrations in AD (odds ratio 0.83; 95% confidence interval 0.66 - 0.96; p=0.046). The inverse association between zinc status and AD in children aged 5 - 12 years in our setting is consistent with the international literature. The clinical importance of decreased zinc levels in AD is not yet known. Further investigation into relevant underlying mechanisms seems warranted given the global reach of AD, its effect on quality of life, and the low cost of potential zinc-based interventions.

Assessment of Hair Zinc in the School Children in Kayseri, Turkey.

Zinc is an essential micronutrient for the organism and is critical for the functional and structural integrity of cells. Determination of the amount of trace element concentrations in tissues such as hair samples have been used for the evaluation of the metabolic status especially in children. Unlike serum zinc, concentrations of zinc in hair are more stable and indicative of variations over time. The purpose of this study is to assess the zinc status of healthy school-age children in Kayseri (Turkey) by measuring the zinc level in hair samples and its association with BMI and the frequency of intake of zinc-rich foods. A total of 527 healthy children, including preadolescent (n = 360) aged 6-10years and adolescent (n = 167) aged 11-15years were included in this study. Hair samples were analyzed for zinc content by the inductively coupled plasma-mass spectrophotometry. Analysis of 527 healthy children showed that the mean hair zinc level was 186 ± 77μg/g. Mean hair zinc level was lower in preadolescent age group than adolescents. There was no significant relationship between the monthly income of the family and the zinc-rich food intake and the zinc level of the hair. Our study shows that samples for analysis of zinc can be obtained with a noninvasive method for determining cases of deficiency during periods of rapid growth. However, further studies are needed to determine the normal tissue zinc level in healthy children, especially in our country and including different geographical regions.

Correlation between hair zinc level and cognitive function in elderly population

Introduction: Neurodegenerative disease is the most problem in elderly. Amyloid β (Aβ) accumulation is the major cause of cognitive impairment. Zinc has an important role in antioxidant and Aβ accumulation process. This study aimed to evaluate the correlation between hair zinc level and cognitive function in elderly.Methods: A cross sectional study was conducted involving 58 subjects of elderly in Jakarta. Subjects were recruited by consecutive sampling. Hair zinc level was measured by inductively coupled plasma emission spectrometer (ICPS) and cognitive function assessed by abbreviated mental test (AMT). Data analysis was done by spearman rank correlation test and p-value less than 0.05 were considered statistically significant.Results: The mean of age was 65.4 ± 4.4 years old and 56.9% of subjects were female. The mean of hair zinc level was 123.23 ± 69.71 µg/gram hair and 32.8% subjects had hair zinc deficiency. There was 91.4% subjects had normal cognitive function. The study showed no correlation between hair zinc level and cognitive function in elderly (p=0.871 ; r=-0.022).Conclusions: There was no correlation between hair zinc level and cognitive function in elderly. Further research is expected to be performed with different level of cognitive function.Keywords: cognitive, elderly, hair zinc level, zinc.

Stunted Toddlers Had Lower Hair Zinc Level Compared to Their Normal Peers: Result from a Case Control Study in Nganjuk.

Stunting is highly prevalent, including in Indonesia. Zinc intake and zinc status contribute to the etiology of stunting. However, zinc status measurement is not easy. Hair zinc level reflects long term exposure to zinc. This study aimed to analyze the difference in hair zinc level of stunted toddlers as compared to normal toddlers. This case-control study was conducted in Nganjuk with 23 stunted toddlers and 23 normal toddlers selected using simple random sampling. Hair zinc level was measured using atomic absorption spectrometry conducted at the Center of Research and Industrial Consultation Laboratory, Surabaya. The inclusion criteria for this study were children aged 24-59 mo, lived in Puskesmas Wilangan work-areas, and had uncoloured hair with minimum length of 1.5 cmthe list of respondents gathered from EPPGBM website, where it provides list of informations consist of data of malnutrition children. The study revealed that mean hair zinc level among stunted toddlers were 146.21±16.83 mg/L while the hair zinc level among the normal toddlers were 157.07±23.11 mg/L. There was significant difference in hair zinc level between stunted toddlers compared to their normal peers. Conclusions: Hair zinc level was associated with stunting and can be considered as biomarker for stunting.

Hubungan Kadar Zinc dan Pola Asuh Ibu dengan Kejadian Stunting pada Anak Usia 2 – 5 Tahun di Kecamatan Panti Kabupaten Pasaman

Stunting is a short body condition based on height according to age (TB / U) whose standard deviation is less than -2 and -3 from the z-score calculation of the WHO child growth standard table. Stunting is an irreversible growth disorder due to inadequate nutrition and recurring infections during the first 1000 days of life. Indicators of chronic malnutrition that occur in a long time so that stunting in children under five, especially at the age of 2-5 years stunting will be clearly visible and is one indicator of chronic nutritional status that can provide an overall picture of the disorder in the past. The causes of stunting are lack of nutrition, infectious diseases, poor parenting, poor environmental sanitation and low health services. Zinc deficiency can cause impaired growth and decreased immunity. One of the biomarkers used is the analysis of hair zinc levels because it can describe chronic zinc levels in the past so it is appropriate to measure zinc levels in the stunting condition which is a long-standing condition of malnutrition. The croos sectional research design was carried out in the Panti District of Pasaman Regency and the West Sumatra Regional Health Laboratory in June to July 2019. The study sample were mothers and children aged 2-5 years as many as 60 people divided into two groups which are stunting and normal children, taken by proportional stratified simple random sampling. Zinc levels were measured by atomic absorption spectrophotometry (AAS) while parenting used questionnaires. Statistical test using Mann Whitney test and Chi Square. The results showed the mean zinc levels in stunting children 154.70 (9-387) µg / g and zinc levels in normal children 241.00 (60-933) µg / g with p = 0.018. parental feeding (p = 0.009), hygiene parenting (p = 0.034). health care parenting (p = 0.017), psychosocial stimulation parenting care (0,000). The conclusion of this study is that there is a significant association between zinc levels and parenting with the incidence of stunting.

Zinc status of riverside populations of the rivers Solimoes and Negro in the state of Amazonas, Brazil

Zinc nutrition has been shown to be critically limiting among urban populations of the central Amazon valley, but no information on the zinc status of rural populations has been published. Nutrition surveys were carried out on the river Solimoes and the river Negro in years 1976/7. Hair samples collected at that time were analysed for their zinc content, by Atomic Absorption Spectrophotometry. The mean hair zinc value of children aged under seven years from the river Negro (140 µg/g) was about one third lower than hair values from the river Solimoes (204 µg/g) with high statistical significance (p&lt; 0.001). Hair zinc levels were influenced by a variety of non-dietary conditions in these riverine children populations, including anthropometric classifications and gastrointestinal parasites, and these are discussed. The significantly lower hair zinc levels in children on the river Negro than in children on the river Solimoes may be part of the reason why young child stunting rates are higher on the river Negro. The importance of zinc status for reproduction is also discussed, especially the evidence for relationships to still teratogenesis and still births, the latter being six times more common among mothers on the river Negro than among those on the Solimoes at that time. Although no indicators of maternal zinc status were measured, the findings of zinc deficiency in their young children support the hypothesis that these mothers were also suffering from zinc deficiency. It also suggests poor zinc status may be associated with the lower population densities found along the banks of the river Negro as compared to that of the river Solimoes. The situation seems unlikely to have improved in the forty years since these observations were made and may even be getting worse. Interventions are suggested that would allow this type of situation to be remedied.

Blood and hair zinc levels in children with attention deficit hyperactivity disorder: A meta-analysis.

We summarized the observational studies on the correlation between zinc and attention deficit hyperactivity disorder (ADHD) since 1986, extracted relevant data for meta-analysis to determine the relationship between zinc and ADHD. We searched PubMed, Scopus, Cochrane Library, EMBASE (included EMBASE and Medline), Web of Science and Clinical Trials.gov databases from inception to April 8, 2019. We assessed the blood zinc, hair zinc and ADHD by combined the standardized mean difference (SMD) and 95% confidence interval (CI). Statistical analysis was performed using Stata 14.0. We included 11 studies for meta-analysis. Of these, 8 studies comprising 1311 participants reported blood zinc and 3 studies comprising 206 participants reported hair zinc. The zinc levels in blood (SMD: -0.91, 95% CI: -1.88-0.07, P(SMD) < 0.068), and hair (SMD: 1.42, 95% CI: -4.49-7.33, P(SMD) = 0.638) not significantly compare ADHD with controls. Nevertheless, high heterogeneity (I2 > 97.3%) emerged among the included studies. The subgroup analysis showed that the heterogeneity of samples >100 group was significantly reduced. The sensitivity analysis found that the results changed significantly after excluding the only cross-sectional study. In conclusion, our meta-analysis showed that there was no statistically significant difference in blood zinc and hair zinc levels between ADHD children and adolescents compared with healthy children and adolescents.

Metal and essential element levels in hair and association with autism severity

BackgroundAutism Spectrum Disorder (ASD) is a complex disorder with heterogeneous etiology and wide clinical severity which supports the needs of recognizing biological and clinical features in patient subsets. The present study aimed to understand possible associations between the hair levels of metals and essential elements and some specific features of ASD measured by the Autism Diagnostic Observation Schedule (ADOS) that represents the gold-standard instrument to objectively confirm ASD diagnosis. MethodsA cross-sectional study was performed in the province of Catania (Sicily, South Italy). Forty-eight subjects with ASD (70.8% male), aged from 2 to 17 years were studied. Metals (Li, Be, Al, Ni, As, Mo, Cd, Hg, U, Pb) and essential trace elements (Cr, Co, Mn, Zn, Cu, Se) were quantified in hair by inductively coupled plasma mass spectrometry analysis. Participants were characterized by measuring the severity of autism symptoms and cognitive levels. ResultsA significant and positive correlation was found between hair metal burden (lead, aluminum, arsenic and cadmium levels) and severity of ASD symptoms (social communication deficits and repetitive, restrictive behaviors). Hair zinc level were inversely related with age while there was a negative, significant association between hair zinc level and severity of autistic symptoms (defective functional play and creativity and increase of stereotyped behavior). Lead, molybdenum and manganese hair levels were inversely correlated with cognitive level (full intelligence quotient) in ASD individuals. ConclusionsThe present study suggests the importance to combine metallomics analysis with pertinent disease features in ASD to identify potential environmental risk factors on an individual level possibly in the early developmental period.

Evaluate the effect of cadmium on levels of zinc in scalp hair and blood samples of smoker and nonsmoker psoriatic patients at different stage.

Psoriasis, a skin inflammatory disease, originates from dysregulated interactions of the immune system and environmental factors. In the present study, cadmium (Cd) and zinc (Zn) were analyzed in biological samples (blood and scalp hair) of smoker and nonsmoker males who have mild and severe psoriasis. The patients were evaluated according to criteria based on the standard clinical diagnosis and classified into mild and severe psoriasis groups using the Psoriasis Area Severity Index (PASI) score. Both elements were determined by atomic absorption spectrometry after matrix oxidation. In smoker psoriatic patients, the level of Cd in biological samples was significantly increased. The Zn was significantly decreased in smoker mild and severe psoriatic patients as related to nonsmokers' referents and patients. The resulted data indicated that the levels of Zn in smoker referents were about 5.0% lower than nonsmoker's referents. While the concentrations of Zn in blood samples of nonsmoker's mild and severe psoriatic patients have 17.8 to 33.3% lower than nonsmoker's referents. The results indicate that the level of Cd in blood samples of referent smokers has ≥ 25% than nonsmokers, whereas the psoriatic patients at different stages have two- to threefold higher Cd in both biological samples.

Correlation between Hair Zinc Level and Cognitive Function in Elderly

Background and Objectives : Neurodegenerative disease is the most problem in elderly. Amyloid β (Aβ) accumulation is the major cause of cognitive impairment. Zinc has an important role in antioxidant and Aβ accumulation process. This study aimed to evaluate the correlation between hair zinc level and cognitive function in elderly.Methods : A cross sectional study was conducted involving 58 subjects of elderly in Jakarta. Subjects were recruited by consecutive sampling. Hair zinc level was measured by inductively coupled plasma emission spectrometer (ICPS) and cognitive function assessed by abbreviated mental test (AMT). Data analysis was done by spearman rank correlation test[DN1] and p-value less than 0.05 was considered statistically significant.Results : The mean of age was 65.4 ± 4.4 years old and 56.9% of subjects were female. The mean of hair zinc level was 123.23 ± 69.71 µg/gram hair and 32.8% subjects had hair zinc deficiency. There was 91.4% subjects had normal cognitive function. The study showed no correlation between hair zinc level and cognitive function in elderly (p=0.871 ; r=-0.022).Conclusion : There was no correlation between hair zinc level and cognitive function in elderly. Further research is expected to be performed with different level of cognitive function.

Are There Differences in Hair Mineral Concentrations Between Metabolically Healthy and Unhealthy Obese Adults?

Obesity is a risk factor for metabolic syndrome, dyslipidemia, hypertension, insulin resistance, type 2 diabetes mellitus, and cardiovascular disease. However, obesity is not a homogenous state and not all subjects in an obese population are at an increased risk for metabolic abnormalities. Thus, obesity types can be subdivided into metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO) according to metabolic status. Body minerals are important and are involved in various metabolic processes that may be related to obesity. Thus, this study determined whether hair mineral concentrations differ between MHO and MUO adults. The associations between metabolic risk factors and hair mineral concentrations were analyzed in 141 obese Korean adults (62 MHO subjects and 79 MUO subjects). The MUO subjects showed significantly higher triglyceride levels, systolic blood pressure, waist circumference and body mass index, lower high-density lipoprotein cholesterol levels, and greater insulin resistance as reflected by the homeostasis model assessment-insulin resistance (HOMA-IR) index compared with MHO subjects. No significant differences in hair mineral concentrations were detected between MHO and MUO adults. Hair iron and cobalt concentrations were significantly negatively correlated with blood pressure in subjects with MHO. In addition, hair zinc concentration was associated with decreased systolic blood pressure. The results of this study suggest that mineral status in obese adults may play a role in metabolic abnormalities. Further studies with a larger number of subjects are warranted to identify the nature of the relationship between hair mineral status and metabolic risk in MHO and MUO subjects.

Zinc and atopic dermatitis: a systematic review and meta-analysis.

Zinc plays a central role in skin integrity via barrier and immune mechanisms and may also be relevant in the pathogenesis of atopic dermatitis (AD). However, little is known about the relationship between zinc and AD. We performed a systematic review to determine (i) the association between zinc levels or zinc deficiency and AD and (ii) the efficacy of oral zinc supplementation in the treatment of AD. We searched PubMed, Scopus, Web of Science and article references for observational studies on zinc levels or zinc deficiency in participants with AD vs. controls and for randomized control trials (RCTs) on zinc supplementation in AD. For observational studies, we calculated pooled standardized mean differences (SMDs) or odds ratios (ORs) along with 95% confidence intervals (CIs) using a random effects model. We included 14 observational studies and two RCTs. The pooled SMD demonstrated significantly lower serum (SMD 0.66, 95% CI 0.21-1.10, P=0.004), hair (SMD 0.95, 95% CI 0.38-1.52, P=0.001) and erythrocyte (SMD 0.95, 95% CI 0.38-1.52, P=0.001) zinc levels in participants with AD compared to controls. Pooled unadjusted data from three studies showed a non-significant increased odds of AD in those with zinc deficiency compared with those without zinc deficiency (OR = 1.50, 95% CI 0.71-3.16, P=0.28). One RCT of oral zinc supplementation among AD patients with zinc deficiency showed improvement in extent and severity of AD, while another RCT among all AD patients showed no significant improvement. All the studies were of low or moderate quality. We conclude that low serum, hair and erythrocyte zinc levels are associated with AD. However, the poor quality of included studies makes interpretation of these results problematic. High-quality observational studies are needed to confirm the association between low zinc levels and AD, and RCTs are required to evaluate the merit of zinc supplementation for the treatment or prevention of AD.

Zawartość magnezu i cynku we włosach:przegląd systematyczny i metaanaliza

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