Basal urinary zinc/creatinine ratio as an indicator of dietary zinc intake in healthy adult women

OBJECTIVE: To study, in healthy women, the correlation between the basal urinary zinc/creatinine ratio and dietary zinc intake. SUBJECTS: A group of 36 healthy female University students was evaluated. Mean age and body weight were, respectively, 25.6+/-3.3 years and 54.4+/-7.0 kg. METHODS: Basal urine was collected; Zn was determined by AAS and Creatinine (Creat) by the Jaffe method. A nutritional survey of seven days was recorded. Mean daily dietary intake of energy (DE) and zinc (DZn) were calculated according to the INCAP and English or German Food Composition Tables, respectively. RESULTS: Mean dietary daily intake were as follows (x +/- SD): Energy (kcal): 1606+/-570; zinc (mg): 9.1+/-3.8; basal urine Zn/Creat ratio: 0.41+/-0.24. Individual values of the Zn/Creat ratio correlated with dietary Zn (r=0.481, p=0.0339); data grouped according to ranges of dietary Zn fit the following equation: Zn/Creat=0.160+/-0.034 DZn (mg/day); (r=0.870, p=0.00497). CONCLUSIONS: These results showed that the basal urinary Zn/Creat ratio could be a useful indicator of dietary Zn intake in healthy adult women.     

Factors Influencing Zinc Status of Apparently Healthy Indians

Objectives: To identify dietary, environmental and socio-economic factors associated with mild zinc deficiency, three zinc status indices; erythrocyte membrane zinc (RBCMZn), plasma zinc and super oxide dismutase (SOD) were assessed in free living and apparently healthy Indian population.

Methods: Dietary patterns of 232 men and 223 women (20–65 yr) from rural, industrial and urban regions of Western India were evaluated by food frequency questionnaire. RBCMZn was estimated using atomic absorption spectrometry, hemoglobin and serum ceruloplasmin by spectrophotometer. On a sub sample (48 men and 51 women) plasma zinc and SOD were also assessed.

Results: Mean RBCMZn was 0.5 ± 0.1 μmols/g protein with 46% individuals showing zinc deficiency. Mean plasma zinc was 0.98 ± 0.12 μg/mL with 25% men and 2.5% women having values below normal range. Mean SOD was 0.97 ± 0.1 (u/mL cells). A significant positive correlation was observed between intakes of green leafy vegetables, other vegetables and milk products with RBCMZn status (p < 0.05). But these were not correlated with plasma zinc (p > 0.2). Cereal and legume intakes were negatively correlated with RBCMZn (p < 0.05) but positively correlated with plasma zinc (p < 0.05) and not correlated with SOD (p > 0.2). Fruit and other vegetable intake were positively correlated with SOD (p < 0.05) alone. Logistic regression analyses revealed that RBCMZn was positively associated with intakes of β-carotene, zinc and environmental conditions and negatively associated with family size (p < 0.05). Plasma zinc indicated positive association with zinc, thiamin and riboflavin intakes (p < 0.05) and SOD showed negative association with iron and family size.

Conclusion: RBCMZn was a more sensitive indicator of long-term zinc status than plasma zinc and SOD. Prominent determinants of zinc status were intakes of beta-carotene and zinc along with environmental conditions and family size.     

Effect of Micronutrient-Fortified Milk on Zinc Intake and Plasma Concentration in Adolescent Girls

Objective: To assess the effect of dietary fortified milk with zinc and other micronutrients on zinc intake and plasma zinc content of adolescent girls.

Methods: The study included 108 schoolgirls (12–18 years old) from northwest Mexico, randomly assigned to either the control group (CG; n = 55) or the intervention group consuming a regular diet plus fortified milk (MG; n = 53). At the beginning of the study, age, weight, and height were measured. Food intake by the 24-hour recall method and plasma zinc levels assessed by absorption spectrophotometry were determined before and after 27 days of fortified milk intake.

Results: At baseline, no significant group-related differences were observed for energy, protein intake, zinc intake, and plasma zinc level (p > 0.05), and 35.2% of participant girls did not achieve their zinc requirement. After 27 days of treatment, there were no significant differences in energy and protein intake between groups (p > 0.05). Zinc intake was higher for MG than CG (16.7 ± 8.3 mg/d vs 10.5 ± 6.4 mg/d; p < 0.01), and there was a lower proportion of low zinc intake in MG than for CG (7 vs 16, respectively; p = 0.04). In addition, plasma zinc improved in the MG (116.6 ± 26.9 μg/dL, p < 0.01) compared with CG (98.5 ± 26.6 μg/dL), and it was mainly attributed to the fortified milk intake, as the main dietary zinc contributor.

Conclusion: Fortified milk intake is effective in increasing both intake and plasma zinc levels of adolescent Mexican girls; therefore, it could be an adequate strategy for zinc deficiency prevention or correction among adolescent girls.     

Effects of Zinc and Selenium Supplementation on Thyroid Function in Overweight and Obese Hypothyroid Female Patients: A Randomized Double-Blind Controlled Trial

Objective: Zinc (Zn) and selenium (Se) are essential trace elements involved in thyroid hormone metabolism. This study was conducted to investigate the effects of Zn and Se supplementation on thyroid function of overweight or obese female hypothyroid patients in a double-blind, randomized controlled trial.

Methods: Sixty-eight female hypothyroid patients were randomly allocated to one of the 4 supplementation groups receiving Zn + Se (ZS; 30 mg Zn as zinc-gluconate and 200 μg Se as high-selenium yeast), Zn + placebo (ZP), Se + placebo (SP), or placebo + placebo (PP) for 12 weeks. Serum Zn, Se, free and total triiodothyronine (FT3 and FT4), free and total thyroxine (FT4 and TT4), thyroid-stimulating hormone (TSH), and anthropometric parameters were measured. Dietary intake was recorded using 24-hour food recall. Physical activity questionnaire was completed.

Results: No significant alterations were found in serum Zn or Se concentrations. Mean serum FT3 increased significantly in the ZS and ZP groups (p < 0.05) but this effect was significant in the ZP group compared to those in SP or PP groups (p < 0.05). Mean serum FT4 increased and TSH decreased significantly (p < 0.05) in the ZS group. TT3 and TT4 decreased significantly in the SP group (p < 0.05). Mean FT3:FT4 ratio was augmented significantly in the ZP group (p < 0.05). No significant treatment effects were found for TT3, FT4, TT4, or TSH between groups.

Conclusion: This study showed some evidence of an effect of Zn alone or in combination with Se on thyroid function of overweight or obese female hypothyroid patients.     

Bioavailability of Zinc in Wistar Rats Fed with Rice Fortified with Zinc Oxide

The study of zinc bioavailability in foods is important because this mineral intake does not meet the recommended doses for some population groups. Also, the presence of dietary factors that reduce zinc absorption contributes to its deficiency. Rice fortified with micronutrients (Ultra Rice^®) is a viable alternative for fortification since this cereal is already inserted into the population habit. The aim of this study was to evaluate the bioavailability of zinc (Zn) in rice fortified with zinc oxide. During 42 days, rats were divided into four groups and fed with diets containing two different sources of Zn (test diet: UR^® fortified with zinc oxide, or control diet: zinc carbonate (ZnCO₃)), supplying 50% or 100%, respectively, of the recommendations of this mineral for animals. Weight gain, food intake, feed efficiency ratio, weight, thickness and length of femur; retention of zinc, calcium (Ca) and magnesium (Mg) in the femur and the concentrations of Zn in femur, plasma and erythrocytes were evaluated. Control diet showed higher weight gain, feed efficiency ratio, retention of Zn and Zn concentration in the femur (p < 0.05). However, no differences were observed (p > 0.05) for dietary intake, length and thickness of the femur, erythrocyte and plasmatic Zn between groups. Although rice fortified with zinc oxide showed a lower bioavailability compared to ZnCO₃, this food can be a viable alternative to be used as a vehicle for fortification.     

Potential Antioxidant Effects of Zinc and Chromium Supplementation in People with Type 2 Diabetes Mellitus

Objective: To determine the effects of combined zinc (Zn) and chromium (Cr) supplementation on oxidative stress and glucose homeostasis of people with type 2 diabetes.

Design: Tunisian adult subjects with HbA1C >7.5% were supplemented for 6 months with 30 mg/d of Zn as Zn gluconate or 400 μg/d of Cr as Cr pidolate or combined Zn/Cr supplementation or placebo. The effects of supplementation on plasma zinc (Zn), copper (Cu), selenium (Se), urinary Zn, Cr, plasma thiobarbituric acid reactive substances (TBARS), Cu-Zn superoxide dismutase (SOD) and Se glutathione peroxidase (GPx) in red blood cells, blood lipids and lipoproteins, HbA1C and fasting glucose were measured at the beginning of the study and after six months.

Results: At the beginning of the study, more than 30% of the subjects may have been Zn deficient with plasma Zn values less than 10.7 μmol/L, whereas levels of plasma Cu, Se and antioxidant RBC enzyme activities were in the normal ranges. Following supplementation, there were significant decreases of plasma TBARS in the Cr (13.6%), Zn (13.6%) and Zn/Cr (18.2%) groups with no significant changes in the placebo group. The value for the TBARS of the control healthy Tunisian subjects was 2.08 ± 0.04 μmol/L and that of the Tunisian subjects with diabetes was 3.32 ± 0.05 μmol/L. This difference of 1.24 μmol/L between the control group and the subjects with diabetes was reduced from 36% to 50% in the three supplemented groups. Supplementation did not modify significantly HbA1C nor glucose homeostasis. No adverse effects of Zn supplementation were observed on Cu status, HDL cholesterol nor interactions in Zn or Cr.

Conclusions: These data suggest the potential beneficial antioxidant effects of the individual and combined supplementation of Zn and Cr in people with type 2 DM. These results are particularly important in light of the deleterious consequences of oxidative stress in people with diabetes.     

Current Zinc Intake and Risk of Diabetes and Coronary Artery Disease and Factors Associated with Insulin Resistance in Rural and Urban Populations of North India

Objective: To determine the association between current zinc intake and prevalence of coronary artery disease (CAD) and diabetes as well as factors associated with insulin resistance.

Design, Subjects and Methods: In this cross sectional survey, 3575 subjects, aged 25 to 64 years, including 1769 rural (894 men, 875 women) and 1806 urban (904 men, 902 women) subjects were studied. The survey methods included questionnaires for 7-day food intake record, physical examination, and electrocardiography using World Health Organization criteria.

Results: The prevalence of CAD, diabetes and glucose intolerance was significantly higher among subjects consuming lower intakes of dietary zinc. There was a higher prevalence of hypertension, hypertriglyceridemia and low high-density lipoprotein cholesterol levels which showed significant upward trend with lower zinc intakes. Serum lipoprotein (a) and 2-hour plasma insulin levels also were associated with low zinc intake. Multivariate logistic regression analysis after adjustment for age showed that zinc intake and CAD were inversely associated. Serum zinc (odds ratio:men 0.77, women 0.57), serum triglycerides (men 0.86, women 0.81), blood pressure (0.83 men, women 0.76), diabetes mellitus (men 0.90, women 0.85), central obesity (men 0.88, women 0.87), glucose intolerance (men 0.66, women 0.57) and low high-density lipoprotein cholesterol (men 0.72, women 0.70) were significant risk factors for CAD (explained by tertiles of zinc status) in urban subjects. These associations were not observed in rural subjects.

Conclusion: Lower consumption of dietary zinc and low serum zinc levels were associated with an increased prevalence of CAD and diabetes and several of their associated risk factors including hypertension, hypertriglyceridemia and other factors suggestive of mild insulin resistance in urban subjects.     

Association between Dietary Conjugated Linoleic Acid and Bone Mineral Density in Postmenopausal Women

Objective: To determine if dietary conjugated linoleic acid (CLA) is associated with bone mineral density (BMD) of different skeletal sites in postmenopausal women.

Methods: A cross-sectional analysis in 136 Caucasian, healthy, postmenopausal women, mean age 68.6 years. BMD and soft tissue were assessed by dual energy x-ray abosorptiometry (DXA). Energy, calcium, protein, fat, CLA and other relevant nutrients were estimated using 3 day dietary records. Supplement use was recorded as well. Current and past physical activity were determined using the Allied Dunbar National Fitness Survey for older adults.

Results: CLA (63.1 ± 46.8 mg, mean ± SD) was a significant predictor of Ward’s triangle BMD (p = 0.040) in a multiple regression model containing years since menopause (18.5 ± 8.4 y), lean tissue, energy intake (1691 ± 382 kcal/day) dietary calcium (873 ± 365 mg), protein (70.6 ± 18.6 g), fat (57.9 ± 23.9 g), zinc (19.2 ± 13.6 mg), and current and past physical activity, with R²_adj = 0.286. Subjects were also divided into groups below (Group 1) and above (Group 2) the median intake for CLA. Group 2 had higher BMD in the forearm, p = 0.042, and higher BMD in the hip, lumbar spine and whole body, however statistical significance was not reached.

Conclusion: These findings indicate dietary CLA may positively benefit BMD in postmenopausal women. More studies are warranted examining the relationship between dietary CLA and BMD.     

Evaluation of a Diet Containing Probiotics and Zinc for the Treatment of Mild Diarrheal Illness in Children Younger Than One Year of Age

Objectives: Supplementation of probiotics and supplementation of zinc during acute gastroenteritis in children have been shown to exert positive effects on diarrhea duration and severity. Our aim was to evaluate a new diet enriched with zinc and probiotic bacteria in the treatment of acute gastroenteritis in young children.

Methods: In a double blind prospective study, 65 children aged 6–12 months were randomized to receive 6 × 10⁹ colony forming units of Streptococcus thermophilus, Bifidobacterium lactis, Lactobacillus acidophilus (2 × 10⁹ of each strain), 10 mg of zinc/day, and 0.3 grams of fructo-oligosaccharides in the supplemented group (n = 33) or placebo (n = 32), given in a soy protein based rice cereal. For each child, age, sex, weight, degree of dehydration, the presence of fever or vomiting, stool frequency and consistency were recorded daily until diarrhea resolution.

Results: Diarrhea resolution occurred after 1.43 ± 0.71 days in the supplemented group vs. 1.96 ± 1.24 in the control group (p = 0.017). In the subset of children who presented with vomiting, time to vomiting resolution was 0.27 ± 0.59 vs. 0.81 ± 0.91 days in the supplemented and control groups, respectively (p = 0.06). On day 3, there was only 1 child with watery stools in the supplemented group versus 10 children in the control group (p = 0.02).

Conclusions: In our series, the feeding of a cereal containing Streptococcus thermophilus, Bifidobacterium lactis, Lactobacillus acidophilus and zinc, reduced the severity and duration of acute gastroenteritis in young children. However, whether this combination is better than either the addition of probiotics or zinc alone is yet to be determined.     

代谢平衡法与粪便监测法评价藏族成年男子膳食锌吸收率的比较

目的:比较代谢平衡法(MB)和粪便监测法(FM)评价藏族成年男子膳食锌(Zn)吸收率。方法:进行14d人体现场代谢试验,受试者于D5晚一次性口服浓集67Zn的稳定性同位素示踪剂4.0mg及稀土元素镱(Yb)1.0mg,口服卡红标记、并收集D4~12的粪便和尿液样品,同时收集膳食、饮水样品;用感耦等离子体质谱仪测定粪样67Zn/68Zn的比值,并用原子吸收分光光度计分析所收集样品中的锌含量,比较用两种方法测定该人群膳食Zn吸收率的结果。结果:MB和FM评价藏族成年男子膳食Zn吸收率分别为(23.8±3.9)%、(21.4±4.3)%,二者的差异(配对t检验)和相关性(Pearson)均有统计学意义;未吸收的Zn示踪剂和Yb经胃肠道排出情况几乎一致,主要在口服后5d内排出。结论:14d代谢试验评价膳食Zn吸收率时,MB略高于FM,后者的试验期可依据Yb的排出情况缩短至4~5d。两种方法评价的结果都表明藏族成年男子膳食Zn吸收尚可。     

葡萄糖酸锌对人体内环境锌铜水平影响的研究

目的:探讨高锌摄入对血压、心率及人体内环境锌铜水平的影响。方法:选择饮食结构及饮食习惯相同的健康成人38例口服葡萄糖酸锌(50 mg/d),连续8周,于服葡萄糖酸锌前、后4、8周及停锌后4周4次查体,同时取血、尿、发测定锌、铜含量。结果:服锌后收缩压降低,停药后恢复到原来水平,血、尿、发锌含量明显升高(P<0.01),并且随锌摄入量的增加持续升高,Zn/Cu增大(P<0.05~0.01),停药后血、发锌含量仍高于服前水平(P<0.05~0.01),铜含量无变化(P>0.05)。结论:口服葡萄糖酸锌后内环境锌铜代谢失衡,停锌后短期内不能恢复原来水平。     

A Mediterranean Dietary Style Improves Calcium Utilization in Healthy Male Adolescents

Objective: To examine the effects of consuming a diet based on the Mediterranean patterns on calcium availability and metabolism in male adolescents.

Design: A longitudinal study divided into two periods: a 3-day basal period, during which the subjects (n = 20; 12.9 ± 1.14 years) consumed their usual diet (basal diet, BD), and a 28-day nutritional intervention period, in which an intervention Mediterranean-type diet - was consumed (ID).

Methods: Dietary calcium utilization was assessed by means of calcium intake in food and calcium output in feces and urine as measured by flame absorption spectrophotometry. In addition, markers of calcium metabolism (serum Ca, parathyroid hormone and total alkaline phosphatase) and bone resorption (urine deoxypiridinoline) were measured.

Results: No differences in total calcium intake were found between the two diets, but food sources of dietary calcium varied significantly. Compared with the BD, the consumption of the ID resulted in significant increases in calcium absorption (～ 40%, p = 0.04) and retention (～ 80%, p = 0.008), and a considerable decrease in urinary calcium excretion (～ 40%, p = 0.01).The variations observed in bone markers reflected a higher bone turnover rate after the ID consumption.

Conclusions: A varied diet based on Mediterranean diet patterns during adolescence greatly improves dietary calcium utilization, which may help to maximize the peak bone mass and prevent related diseases, such as osteoporosis.     

High zinc content of scalp hair in rural West Java: A rice‐eating community

Zinc concentrations in scalp hair were determined in 50 Sundanese villagers in West Java, Indonesia. Hair zinc levels increased with age until about 20 years of age and then became constant. The mean level and S.D. of the zinc concentration in adults aged 20 years or more was 199.8 ± 26.7 μg/g (n = 36), which was higher than the reported values in several countries. Our previous study revealed that the dietary zinc intake amounted to 24.9 mg/day for adults and the high consumption of rice, their staple food, contributed 60% of the total daily zinc intake. Although there are some problems in the Sundanese diet such as a shortage of animal products, a diet depending much on rice seems to have an advantage as concerns the nutritional status of zinc.     

Zinc Fortification Decreases ZIP1 Gene Expression of Some Adolescent Females with Appropriate Plasma Zinc Levels

Zinc homeostasis is achieved after intake variation by changes in the expression levels of zinc transporters. The aim of this study was to evaluate dietary intake (by 24-h recall), absorption, plasma zinc (by absorption spectrophotometry) and the expression levels (by quantitative PCR), of the transporters ZIP1 (zinc importer) and ZnT1 (zinc exporter) in peripheral white blood cells from 24 adolescent girls before and after drinking zinc-fortified milk for 27 day. Zinc intake increased (p < 0.001) from 10.5 ± 3.9 mg/day to 17.6 ± 4.4 mg/day, and its estimated absorption from 3.1 ± 1.2 to 5.3 ± 1.3 mg/day. Mean plasma zinc concentration remained unchanged (p > 0.05) near 150 µg/dL, but increased by 31 µg/dL (p < 0.05) for 6/24 adolescents (group A) and decreased by 25 µg/dL (p < 0.05) for other 6/24 adolescents (group B). Expression of ZIP1 in blood leukocytes was reduced 1.4-fold (p < 0.006) in group A, while for the expression of ZnT1 there was no difference after intervention (p = 0.39). An increase of dietary zinc after 27-days consumption of fortified-milk did not increase (p > 0.05) the plasma level of adolescent girls but for 6/24 participants from group A in spite of the formerly appropriation, which cellular zinc uptake decreased as assessed by reduction of the expression of ZIP1.     

Development of a Self-Assessment Instrument to Determine Daily Intake and Variability of Dietary Vitamin K

Objective: To develop and validate a brief, self-assessment instrument (K-Card) to determine daily variations in dietary vitamin K₁ (phylloquinone) intake for use in patients receiving oral warfarin anticoagulant therapy.

Methods: The K-Card was designed to include a checklist of selected common foods and beverages providing ≥ 5 μg vitamin K per serving in American diets and items with lower vitamin K content typically consumed in quantities which contribute significantly to total vitamin K intake. The K-Card was validated against records of weighed food intake from thirty-six healthy volunteers, 20 to 40 and 60 to 80 years of age, whose phylloquinone intakes and plasma concentrations had been previously measured by the Metabolic Research Unit, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA USA. Future use of the K-Card by patients was simulated by a single investigator using 108 one-day weighed food records to estimate phylloquinone intakes. Dietary phylloquinone calculated from the K-Card was compared to the values of phylloquinone intake from the diet records collected on the same days, and to fasting plasma phylloquinone concentrations obtained from the same individuals on the following day.

Results: The mean dietary phylloquinone intake (± SEM) was 138.8 ± 15.7 μg for the K-Cards compared to 136.0 ± 15.8 μg for the diet records (p = 0.067). Bland-Altman limits of agreement between quantities of dietary phylloquinone calculated from the K-Card and values obtained from the weighed food records were ± 38 μg.

Conclusion: In this simulation, the K-Card provided an accurate estimate of dietary phylloquinone intake and therefore deserves further testing for use by patients receiving coumarin-based anticoagulant therapy to determine whether variability in dietary patterns contributes to disruptions in anticoagulant drug efficacy and safety.     

Zinc Deficiency Induces Vascular Pro-Inflammatory Parameters Associated with NF-κB and PPAR Signaling

Objectives: Marginal intake of dietary zinc can be associated with increased risk of cardiovascular diseases. In the current study we hypothesized that vascular dysfunction and associated inflammatory events are activated during a zinc deficient state.

Design: We tested this hypothesis using both vascular endothelial cells and mice lacking the functional LDL-receptor gene.

Results: Zinc deficiency increased oxidative stress and NF-κB DNA binding activity, and induced COX-2 and E-selectin gene expression, as well as monocyte adhesion in cultured endothelial cells. The NF-κB inhibitor CAPE significantly reduced the zinc deficiency-induced COX-2 expression, suggesting regulation through NF-κB signaling. PPAR can inhibit NF-κB signaling, and our previous data have shown that PPAR transactivation activity requires adequate zinc. Zinc deficiency down-regulated PPARα expression in cultured endothelial cells. Furthermore, the PPARγ agonist rosiglitazone was unable to inhibit the adhesion of monocytes to endothelial cells during zinc deficiency, an event which could be reversed by zinc supplementation. Our in vivo data support the importance of PPAR dysregulation during zinc deficiency. For example, rosiglitazone induced inflammatory genes (e.g., MCP-1) only during zinc deficiency, and adequate zinc was required for rosiglitazone to down-regulate pro-inflammatory markers such as iNOS. In addition, rosiglitazone increased IκBα protein expression only in zinc adequate mice. Finally, plasma data from LDL-R-deficient mice suggest an overall pro-inflammatory environment during zinc deficiency and support the concept that zinc is required for proper anti-inflammatory or protective functions of PPAR.

Conclusions: These studies suggest that zinc nutrition can markedly modulate mechanisms of the pathology of inflammatory diseases such as atherosclerosis.     

Effects of Egg Consumption and Choline Supplementation on Plasma Choline and Trimethylamine-N-Oxide in a Young Population

ABSTRACT

Background: Plasma trimethylamine-N-oxide (TMAO) concentrations have been associated with cardiovascular disease risk. Eggs are a rich source of choline, which is a precursor of TMAO.

Objective: The effects of egg intake versus daily choline supplementation were evaluated on plasma choline and TMAO in a young, healthy population.

Methods: Thirty participants (14 males, 16 females; 25.6 ± 2.3 years; body mass index = 24.3 ± 2.9 kg/m²) were enrolled in this 13-week crossover intervention. After a 2-week washout, participants were randomized to consume either 3 eggs/d or a choline bitartrate supplement (～ 400 mg choline total in eggs or supplement) for 4 weeks. Following a 3-week washout, participants were switched to the alternate treatment. Dietary records were measured at the end of each period. Plasma TMAO and choline were measured at baseline and at the end of each dietary intervention. Gene expression of scavenger receptors associated with plasma TMAO were quantified at the end of each intervention.

Results: Compared to the choline supplement, intake of total fat, cholesterol, selenium, and vitamin E were higher (p < 0.05), whereas carbohydrate intake was lower (p < 0.001) with consumption of 3 eggs/d. Fasting plasma choline increased 20% (p = 0.023) with egg intake, while no changes were observed with choline supplementation. Plasma TMAO levels were not different between dietary treatments or compared to baseline.

Conclusions: Dietary choline appears to be more bioavailable via egg consumption when compared to a choline supplement. Plasma TMAO concentrations were not affected in healthy participants after 4 weeks of taking ～400 mg/d choline either via eggs or choline supplementation.     

Current dietary zinc intake has a greater effect on fractional zinc absorption than does longer term zinc consumption in healthy adult men

BACKGROUND: No studies have examined the independent effects of current and longer-term dietary zinc intakes on zinc absorption. OBJECTIVE: We determined the effects of current compared with longer-term zinc intake on fractional zinc absorption (FZA). DESIGN: We studied 9 men whose usual zinc intakes were >11 mg/d. FZA was measured at baseline, depletion (0.6 mg Zn/d for 1 wk and 4 mg Zn/d for 5 wk), and repletion (11 mg Zn/d for 4 wk with 20 mg supplemental Zn/d for first 7 d). During 2 successive days after each dietary period, subjects consumed either adequate-zinc meals (11 mg Zn/d) with a zinc stable isotope tracer for 1 d, followed by low-zinc meals (4 mg Zn/d) with zinc tracer, or vice versa. Five days after oral dosing, a zinc tracer was infused intravenously. FZA was measured with the use of a modified double isotope tracer ratio method with urine samples collected on days 5-7 and 10-12 of absorption studies. RESULTS: Plasma and urinary zinc did not vary by dietary period. Mean FZA was greater from low-zinc meals than from adequate-zinc meals (60.9% +/- 13.8% compared with 36.1% +/- 8.9%; P < 0.0001), whereas mean total absorbed zinc was greater from adequate-zinc meals than from low-zinc meals (3.60 +/- 0.91 compared with 2.48 +/- 0.56; P < 0.0001), regardless of the longer-term dietary period. CONCLUSIONS: FZA was inversely related to current zinc intake, but there was no detectable effect of longer-term dietary zinc. If longer- term zinc intake does modify FZA, such changes are smaller than those caused by current zinc intake, or they occur only after more severe zinc depletion.     

Zinc Nutritional Status in a Series of Children with Chronic Diseases: A Cross-Sectional Study

Background: Zinc is an essential trace element for the normal growth and development of human beings. The main objective was to evaluate the nutritional status of zinc and its association with nutritional indicators in a series of children with chronic diseases. Methods: The prevalence of patients with dietary zinc deficiency or deficit zinc intake (<80% DRI: dietary reference intake) was analyzed through prospective 72 h dietary surveys, and serum zinc deficiency or hypozincemia (≤70 µg/dL in children under 10 years of age in both sexes and in females older than 10 years and <74 μg/dL in males older than 10 years) was measured through atomic absorption spectrophotometry. The participants were classified according to their nutritional status by body mass index (BMI). Results: Mean serum zinc level in obese (87 µg/dL), undernourished (85 µg/dL), and eutrophic children (88 µg/dL) were normal, but in the undernutrition (60% DRI) and eutrophic (67% DRI) groups the mean dietary zinc intake was low compared to that in the obesity group (81% DRI). There were different associations between nutritional parameters, dietary zinc intake, and serum zinc. All patients with hypozincemia had dietary zinc deficiency. Conclusions: In the whole series, 69% of participants showed a zinc intake lower than recommended and might be at high risk of zinc deficiency.