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1.
目的探讨膳食抗氧化维生素摄入对儿童抗氧化能力影响。方法选择河北省唐山市3所小学382名1~6年级学生进行一般情况、食物摄取频率和膳食调查,经家长知情同意后采静脉血测定其血清维生素、抗氧化酶和过氧化产物水平;采用营养计算器V1.6转换数据,SPSS11.5软件进行分析。结果当维生素A(VA)摄入水平>60%且≤80%推荐摄入量(RNI)时,血清VA、丙二醛(MDA)分别为(267.30±80.77)μg/L和(2.52±0.48)μmol/L,与参考值比较,差异均有统计学意义(P<0.05);当类胡萝卜素摄入量<440μg视黄醇当量(RE)时,血清VA低于参考值,MDA高于参考值;<260μg RE时,血清β-胡萝卜素低于参考值;当维生素C(VC)摄入水平分别<100%RNI和<120%RNI时,血清VC、谷胱甘肽过氧化物酶(GSH-Px)<参考值,<140%RNI时,MDA高于参考值;当维生素E(VE)摄入水平<100%适宜摄入量(AI)时,血清VE水平<参考值;<120%AI时,超氧化物歧化酶(SOD)低于参考值,MDA水平高于参考值。结论当VA摄入量≥80%RNI、类胡萝卜素摄入量≥440μg RE、VC摄入量≥140%RNI、VE摄入量≥120%AI时,儿童体内抗氧化指标水平达到正常。  相似文献   

2.
OBJECTIVE: To determine the prevalence of vitamin A deficiency in children aged 6-9 years in northern Ethiopia. METHODS: A cross-sectional study was carried out and the data were analysed for 824 (61.5%) of 1339 eligible children for whom there was complete information on biochemical vitamin A status, dietary vitamin A intake, ocular examination for xerophthalmia, and anthropometry. FINDINGS: The prevalence of xerophthalmia was 5.8%; serum retinol levels were below 0.35 mumol/l and between 0.35 and 0.70 mumol/l in 8.4% and 51.1% of the children respectively. The liver vitamin A reserve (modified relative dose response ratio > or = 0.06) was low in 41.0% of the children. CONCLUSION: The high prevalence of severe vitamin A deficiency in children aged 6-9 years indicates the need to reevaluate the practice of targeting vitamin A supplementation programmes on children under 6 years of age in areas where vitamin A deficiency is endemic.  相似文献   

3.
Data collected as part of a study designed to examine the nutritional status of non-institutionalized elderly individuals, ages 60-100 years, residing in the Boston area were used to investigate the relationship between blood pressure (BP) and vitamin C intake reported by three-day diet records. Four hundred and ten subjects not taking antihypertensive medications were grouped into 5 categories of vitamin C intake: < 60, 60-119, 120-179, 180-239, > or = 240 mg/day. Relative differences in systolic and diastolic BP between subjects consuming > or = 240 mg/day compared to those consuming < 60 mg/day were -6.9% (p < 0.05) and -6.6% (p < 0.05), respectively. The prevalence of elevated BP (systolic > or = 160 mmHg or diastolic > or = 100 mmHg) was approximately 50% lower (p < 0.05) across this range of vitamin C intake. Adjustment of these associations for age, sex, body mass, smoking, dietary sodium:potassium ratio, and other dietary factors did little to alter the relationship between vitamin C and BP. These results lend support to the hypothesis that vitamin C and BP are related, but further research is required to test whether the relationship is causal.  相似文献   

4.
BACKGROUND: Dietary adequacy, as distinct from weight loss, has not been examined thoroughly in a diverse cohort of HIV-infected individuals. OBJECTIVE: An analysis was undertaken to determine the correlates of inadequate dietary intake among HIV-infected adults. DESIGN: In a cross-sectional study of 463 men and 170 women (aged 21-70 y) with HIV infection, dietary adequacy was evaluated by using 3-d diet records. RESULTS: Among nondieting males, whites had higher energy intakes than did nonwhites. Injection drug users consumed less energy than did nonusers. Among nondieting females, only the absence of nausea and vomiting was marginally associated with higher energy intakes. Inadequate energy intake, which occurred in 38% of this population, was independently associated with female sex among nondieters. A significant proportion of the study cohort (52%) was consuming less than the recommended dietary allowance of vitamin A. Inadequate protein intake, found in 11% of the study population, occurred more often in females, those without a caregiving adult in the household, and individuals with reduced appetite. A considerable proportion of the participants (23%) reported that they were dieting to lose weight. CONCLUSIONS: Dietary inadequacy was strongly correlated with being in the sociodemographic groups that are at heightened risk of adverse clinical outcomes. It may be worthwhile to study dietary intake as a potential determinant of the clinical outcomes of HIV infection.  相似文献   

5.
OBJECTIVE: To evaluate nutrient intake from dietary sources for 95 pregnant women enrolled in the Special Supplemental Program for Women, Infants, and Children (WIC). SUBJECTS/SETTING: Women were recruited from Minneapolis and St Paul area WIC clinics between January and June 1999. Based on estimates from the WIC clinics, the study was described to 159 (63%) of the 251 potentially eligible women. Of these 159 women, 107 (67%) completed the in-person interview. Ninety-five (89%) were included in the nutrition analysis. METHODS: Each woman completed a 1-hour in-person interview that included a questionnaire, anthropometric measurements, and a venous blood sample. A shortened Block 98 food frequency questionnaire was used to assess dietary intake. Serum ferritin was measured for 86 women. Means, medians, and standard deviations of dietary intake were explored as well as body mass index distributions. Additionally, the percentage of women consuming less than two thirds of the recommended dietary allowance (RDA) for certain nutrients was calculated. RESULTS: Overall, the women reported consuming only 85% of the RDA for energy. The average percentage of energy from fat was higher than recommended (37% vs 30%). The most notable nutrient shortfall was iron; 90% of the women reported consuming less than 2/3 of the RDA. Additionally, serum ferritin analysis classified 22% of the women with iron-deficiency anemia (<12 mg/L). CONCLUSIONS: Interventions should be designed to decrease fat consumption and increase iron intake among pregnant WIC participants to meet dietary recommendations.  相似文献   

6.
Recent dietary guidelines emphasize micronutrient sufficiency by giving importance to consumption of whole grains and a variety of fruits and vegetables. The objective of this study was to identify a measure of micronutrient quality of diets in adolescent girls consuming a lacto-vegetarian diet. Data were collected on the nutritional status of 630 schoolgirls (ages 10 to 16 years) from Pune city, India, in a cross-sectional survey during 2006-2007. Dietary intakes were assessed by 24-hour recall on 3 nonconsecutive days. Nutrient intakes were calculated from the Indian nutritive value databases. Micronutrient adequacy was expressed as a ratio of observed intake to reference intake. An Adolescent Micronutrient Quality Index (AMQI) was formulated using the Indian and the recent US dietary guidelines. Fasting blood samples were analyzed for plasma levels of vitamin C, beta carotene, and zinc. The average energy intake of the majority of the girls was below the Indian recommended dietary intakes, whereas micronutrient intakes were 50% to 70% lower than recommended dietary intakes. The mean AMQI score was 41.5±9.4. The age of subjects as well as mother's education and occupation were significantly associated with the AMQI. The AMQI was correlated with nutrient intakes and the ratio of observed intake to reference intake (P<0.01) after controlling for energy intake and sociodemographic factors. Higher AMQI scores were associated with higher concentrations of plasma vitamin C (r=0.26), beta carotene (r=0.34), and zinc (r=0.12). The AMQI is a useful measure of the dietary adequacy and micronutrient quality of the diets of adolescent girls consuming lacto-vegetarian diets.  相似文献   

7.
BACKGROUND: The deuterated-retinol-dilution (DRD) technique provides a quantitative estimate of total body stores of vitamin A. However, it is not known whether the technique can detect changes in vitamin A pool size in response to different intakes of vitamin A. OBJECTIVE: Our objective was to determine the responsiveness of the DRD technique to 3 different daily supplemental vitamin A intakes during a period of 2.5-4 mo. DESIGN: Two oral doses of [(2)H(4)]retinyl acetate [52.4 micromol retinol equivalent (RE)] were administered on study days 1 and 91 to 26 men (18-32 y of age) who were consuming controlled, low-vitamin A diets, and receiving daily either 0, 5.2, or 10.5 micromol RE of unlabeled supplemental retinyl palmitate during a 75- or 129-d period. Plasma isotopic ratios of [(2)H(4)]retinol to retinol on day 115 were used to estimate final vitamin A body stores per Furr et al (Am J Clin Nutr 1989;49:713-6). RESULTS: Final ( +/- SD) estimated vitamin A pool sizes were 0.048 +/- 0.031, 0.252 +/- 0.045, and 0.489 +/- 0.066 mmol in the treatment groups receiving 0, 5.2, and 10.5 micromol RE/d, respectively (P < 0.001). Estimated mean changes in vitamin A pool sizes were similar to those expected for the vitamin A-supplemented groups [estimated:expected (95% CI of change in pool size): 1.08 (0.8, 1.2) and 1.17 (1.0, 1.3)]. CONCLUSIONS: The DRD technique can detect changes in total body stores of vitamin A in response to different daily vitamin A supplements. However, abrupt changes in dietary vitamin A intake can affect estimates of total-body vitamin A stores.  相似文献   

8.
OBJECTIVE: To monitor the dietary intake of energy, macro- and micronutrients in asylum seeker children. DESIGN AND SETTING: Cross-sectional study in three asylum seeker centres in The Netherlands. SUBJECTS: Hundred and sixteen children 2-12 years old (86% of the study cohort) provided a dietary history. METHOD: The dietary intake was estimated by 24 h recall, and the origin of the children was classified in three geographic regions: African (n=45), Central Asia (n=34) or Eastern Europe (n=37). RESULTS: The total energy intake from fat was in 24% of the children above 40En%. Seventy per cent of the children above 4 year of age had a saturated fat intake above 10En%. The children from Eastern Europe had a higher intake of fat and disaccharides than the children from the other regions. Among the children, an intake less than 80% of the recommended daily allowances of micronutrients was found for calcium (42%), iron (49%), vitamin A (45%) and vitamin D (80%). An inadequate dietary intake of iron and vitamin D was significantly more seen among the youngest children, whereas an inadequate intake of calcium and vitamin A was found more among the elder children. CONCLUSIONS: The dietary intake of a prominent proportion of these children contains too much fat and insufficient amounts of calcium, iron, vitamin A and vitamin D. The low micronutrient intake of the asylum seeker children can be considered as a nutritional risk. Nutritional education and strategies to improve the macro- and micronutrient intake of asylum seeker children is indicated.  相似文献   

9.
Risk factors for xerophthalmia were assessed in 466 subjects [38% with night blindness (XN), 60% with Bitot's spots (X1B), 2% with corneal xerophthalmia (X2 or X3)] under age 6 y and their village-age-sex-matched control subjects during a community trial. Socioeconomic status and hygiene standards were lowest for households of xerophthalmic children and highest for nonstudy households in the trial population, with values for control households lying in between (P less than 0.001 by linear trend). Risk of xerophthalmia increased with less frequent consumption of dark green leaves, yellow fruits, or egg during weaning, adjusted for current intake and present age [odds ratio (OR) = approximately 3.5]. Exclusion of these same foods from the current diet (except for mango and papaya in older children) was associated with a two- to ninefold excess risk of xerophthalmia, adjusted for weaning influences. Xerophthalmic children aged less than 3 y were generally at higher risk of dietary imbalance than were older children. Xerophthalmia is associated with a chronic, infrequent consumption of key vitamin A foods from weaning through early childhood.  相似文献   

10.
BACKGROUND: Short trials of calcium supplementation show that it reduces loss of bone density in postmenopausal women; longer observational studies do not generally find a lower risk of hip fracture with higher-calcium diets. Fewer studies have focused on vitamin D in preventing postmenopausal osteoporosis or fractures. OBJECTIVE: We assessed relations between postmenopausal hip fracture risk and calcium, vitamin D, and milk consumption. DESIGN: In an 18-y prospective analysis in 72 337 postmenopausal women, dietary intake and nutritional supplement use were assessed at baseline in 1980 and updated several times during follow-up. We identified 603 incident hip fractures resulting from low or moderate trauma. Relative risks (RRs) from proportional hazards models were controlled for other dietary and nondietary factors. RESULTS: Women consuming > or = 12.5 microg vitamin D/d from food plus supplements had a 37% lower risk of hip fracture (RR = 0.63; 95% CI: 0.42, 0.94) than did women consuming < 3.5 microg/d. Total calcium intake was not associated with hip fracture risk (RR = 0.96; 95% CI: 0.68, 1.34 for > or = 1200 compared with < 600 mg/d). Milk consumption was also not associated with a lower risk of hip fracture (P for trend = 0.21). CONCLUSIONS: An adequate vitamin D intake is associated with a lower risk of osteoporotic hip fractures in postmenopausal women. Neither milk nor a high-calcium diet appears to reduce risk. Because women commonly consume less than the recommended intake of vitamin D, supplement use or dark fish consumption may be prudent.  相似文献   

11.
Previous surveys suggested that young children in Northeast Thailand may benefit from vitamin A and/or zinc supplementation. One hundred thirty-three children aged 6-13 y with marginal plasma retinol (less than 1.05 mumol/L) and Zn (less than 12.2 mumol/L) concentrations participated in a double-blind study. They were randomly assigned and supplemented with either zinc (25 mg/d), vitamin A (1500 RE/d), zinc plus vitamin A, or placebo for 6 mo. Biochemical indices of vitamin A (plasma vitamin A, retinol-binding protein) and zinc status (plasma zinc, alkaline phosphatase) increased significantly. The children had adequate liver stores of vitamin A (relative dose response less than 20%). Zinc supplementation resulted in an improvement in vision restoration time (VRT) in dim light (dark adaptometry). Vitamin A and zinc synergistically normalized conjunctival epithelium as measured by conjunctival impression cytology (CIC). Both functional indices, VRT and CIC, showed significant correlations with plasma zinc and vitamin A, respectively. The data suggest that functional improvements in populations with suboptimal vitamin A and zinc nutriture can be accomplished by supplementation with less than two times the recommended dietary allowance of these nutrients.  相似文献   

12.
In recent years several studies have demonstrated the close association of vitamin A deficiency and increased neonatal and childhood morbidity. The breast-fed infant depends on its vitamin A supply solely from maternal milk. Neonatal serum concentration of vitamin A is about one half that found in their mothers. As long as adequate lactational levels of the vitamin are present, the infant's vitamin A status improves over the first 12 months. If maternal vitamin A status is poor in pregnancy it may contribute to the high infant mortality observed in poorly nourished communities. Clinical proof was established only very recently demonstrating a strong correlation between vitamin A status of the mother and intake of the infant. Thus, an adequate vitamin A status during lactation prevents respiratory and diarrheal diseases in breast-fed infants and averts death caused by the diseases. The International Vitamin A Consultative Group (IVACG) suggested that the recommended daily allowance (RDA) of vitamin A in the diet of pregnant women should be 9.3 retinol equivalent (RE)/kg body weight + 100 RE. In marginally nourished populations such as western Rajasthan, it is recommended that daily supplemental doses of 3000 RE (10,000 IU) vitamin A be given during pregnancy provided that the dietary intake is inadequate. For lactating women, the goal is to maintain the highest vitamin A concentration in breast milk. The dietary RDA should be 9.3 RE/kg body weight + 350 RE, provided that the lactating woman did not enter the lactation period in a deficient state. If she did, megadoses of vitamin A (200,000-300,000 IU) may be safely given at parturition or within the first month after birth. This is adequate to maintain a normal range of vitamin A in maternal blood and milk for at least a month.  相似文献   

13.
OBJECTIVE: Levels of vitamin E have been reported to be lower in patients suffering major depression, but whether this is due to inadequate dietary intake or the pathophysiology of depression is not known, and was the subject of the present study. SETTING: Wollongong, Australia. METHODS: Plasma vitamin E (alpha-tocopherol) was measured in 49 adults with major depression, age (mean+/-s.d.): 47+/-12 y. In a subset (n=19) usual dietary intake of vitamin E was determined by diet history. RESULTS: Subjects had significantly lower plasma alpha-tocopherol (4.71+/-0.13 mumol/mmol cholesterol) than has previously been reported for healthy Australians, and plasma alpha-tocopherol was inversely related to depression score (by Beck Depression Inventory) (r=-0.367, P<0.009). Diet analysis indicated that 89% of subjects met or exceeded the recommended intake for vitamin E, and dietary intake was not related to plasma alpha-tocopherol level in this subset. CONCLUSION: These findings suggest that plasma levels of alpha-tocopherol are lower in depression, but this is not likely to be the result of inability to meet recommended dietary intake. .  相似文献   

14.
This 1998 study investigated the association between intake of fish and fish oil during pregnancy and full-term infants' size at birth in an Icelandic fishing community. Healthy women aged 20-40 years of normal weight before pregnancy (body mass index: 19.5-25.5 kg/m(2)) and at 38-43 weeks of gestation were selected randomly. Information on infant size at birth was collected from maternity records. Intake of fish and fish oil in pregnancy was ascertained (n = 491, 80.1%) by using a validated, focused, food frequency questionnaire. Infants of women in the lowest quartile of fish consumption weighed less (p = 0.036), were shorter (p < 0.001), and had a smaller head circumference (p < 0.001) at birth than those of women consuming higher amounts of fish. Infants of women in the highest quartile of fish oil intake (> or =1 tablespoon (11 ml)/day), consuming threefold the recommended dietary allowance of vitamin A and twofold that of vitamin D, were shorter (p = 0.036) and had a smaller head circumference (p = 0.003) than those of women consuming less. Infant size at birth increased with fish consumption, especially for women in the lower quartiles of consumption. Smaller birth size was linked to the highest levels of fish oil intake. Constituents of fish and fish oil might affect birth size differently depending on the amount consumed.  相似文献   

15.
The value of current nutrition information   总被引:1,自引:0,他引:1  
To prevent or delay the occurrence of chronic diseases, scientific bodies from the cardiologic and oncologic disciplines have made recommendations regarding the daily dietary intake of certain macro- and micronutrients. This study assessed the knowledge of a random population of 2,305 individuals comprising members of the public, health care workers, university graduate students, and health club attendees. Segments of this population might be expected to have a greater understanding and ability to implement these dietary recommendations. We found that over 90% of the participants were unaware of the recommendations for calcium, salt, vitamin A, and fiber, and the fiber content in a high fiber cereal. Approximately 80% of the participants were unaware of the recommendations regarding fat intake and could not calculate the fat content of a food product. Almost half of the study population took a vitamin pill daily. Of the subjects who were aware of the correct unit measurement for vitamin A (IU), almost 25% of gave a response that exceeded the recommended daily intake. A majority of this study population were unaware of the dietary recommendations regarding the prevention of cardiovascular events and cancer. Subgroups of this study population that might be expected to have more information regarding these recommendations (i.e., having higher education or being a health care professional) did not display a satisfactory level of knowledge. To further compound the problems of adhering to the recommended guidelines, the labeling of many food products is misleading. The recommendations on dietary intake and the information on food product content must be transmitted to the public in a form that allows for ready application when purchasing and consuming food.  相似文献   

16.
The association of high vitamin A intake and low bone mineral density (BMD) is still controversial. To determine the association of dietary vitamin A intake and serum 25-hydroxyvitamin D (25(OH)D) concentration with BMD, a total of 6481 subjects (2907 men and 3574 women) aged ≥50 years from the Korean National Health and Nutrition Examination Survey (2008–2011) were divided into groups according to dietary vitamin A intake (tertiles) and serum 25(OH)D (<50, 50–75, >75 nmol/L), and evaluated for BMD after adjusting for relevant variables. Mean dietary vitamin A intakes were 737 and 600 μg RE (Retinol Equivalents) in men and women, respectively. Total hip and femoral neck BMD in men and lumbar spine BMD in women were both positively correlated with dietary vitamin A intake in subjects with serum 25(OH)D >75 nmol/L. Among men with serum 25(OH)D <50 nmol/L, both the top (mean 1353 μg RE) and bottom (mean 218 μg RE) tertiles of dietary vitamin A intake had lower BMD than the middle group (mean 577 μg RE). In this population, BMD was the highest among men and women with serum 25(OH)D = 50–75 nmol/L and that there were no differences in BMD by vitamin A intake in these vitamin D adequate groups. This cross-sectional study indicates that vitamin A intake does not affect bone mineral density as long as the serum 25(OH)D concentration is maintained in the moderate level of 50–75 nmol/L.  相似文献   

17.
A well-planned vegetarian diet has been stated to be adequate during pregnancy. The aim of the present study was to compare serum vitamin B-12 and homocysteine concentrations in pregnant women (n = 109) consuming vegetarian and Western diets and to evaluate the adequacy of current dietary reference intakes of vitamin B-12 for these women. Pregnant women adhering to vegetarian diets for at least 3 y, with subgroups of ovo-lacto vegetarians (OLVs; n = 27), low-meat eaters (LME, n = 43), and women eating an average Western diet (control group, n = 39), were recruited. Dietary vitamin B-12 intake, serum vitamin B-12, and plasma total homocysteine (tHcy) concentrations were measured in wk 9-12, 20-22, and 36-38 of pregnancy. During pregnancy serum vitamin B-12 concentrations of ovo-lacto vegetarians (P < 0.001) and low-meat eaters (P = 0.050) were lower than those of the control group. We observed the combination of low serum vitamin B-12 concentrations and elevated plasma tHcy in 22% of ovo-lacto vegetarians, in 10% of low-meat eaters, and in 3% of controls (P = 0.003). In OLVs, serum vitamin B-12 predicted 60% of the plasma tHcy variation (P < 0.001), but in LMEs and controls only <10% (NS). Serum vitamin B-12 concentrations increased and plasma tHcy decreased sharply with increasing dietary intake of vitamin B-12 toward a cutoff point of 3 mug/d. Pregnant women consuming a long-term predominantly vegetarian diet have an increased risk of vitamin B-12 deficiency. Current recommended dietary intakes urgently need reevaluation.  相似文献   

18.
OBJECTIVES: This study estimated dietary vitamin B6 intake and its food sources in young Koreans by using a modified Korean vitamin B6 database. METHODS: Dietary vitamin B6 intake and food sources were estimated from a 3-d recall method for 294 Korean college undergraduates (149 men and 145 women, age range 17 approximately 25 y) who had no health problems. Food portions were estimated by using standard household measurements and published average portions. RESULTS: Average daily intakes of vitamin B6 were 1.57 mg/d in men and 1.44 mg/d in women. Average consumptions of vitamin B6 were 104% of the Korean recommended dietary allowance in men for vitamin B6 and 102% in women. However, 37% of men and 32% of women subjects consumed less than 75% of the Korean recommended dietary allowance for vitamin B6. Major dietary sources of vitamin B6 for Korean young men were pork, rice, onion, potatoes, garlic, mackerel, spinach, egg, carrot, and chicken. Major dietary sources of vitamin B6 for young Korean women were rice, pork, kimchi, beef, bean sprout, potatoes, dumplings, and onions. As for major dietary sources of vitamin B6, the top 20 foods provided nearly 89% of total vitamin B6 in men and 70% of total vitamin B6 in women. CONCLUSIONS: Intake of vitamin B6 by young Koreans was adequate in general, but the supply of vitamin B6 for Koreans should be based on sufficient amounts and specific food sources because fewer foods contribute to vitamin B6 intake of Koreans and these foods are mainly of plant origin and less bioavailable.  相似文献   

19.
Frequent consumption of supplements is a common behavior in adults, as well as children and adolescents. We report on vitamin intake from consuming supplements, taking into account the vitamin intake from fortified and usual foods. A total of 5990 3-d weighed dietary records from 931 German subjects (452 males, 479 females, 2-18 y of age) between 1986 and 2003 from the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study were evaluated. We identified 133 different vitamin-containing supplements in 451 records (7.5%). Slightly more males (8.0%) than females (7.1%) consumed supplements, with highest frequencies found between ages 15 and 18 y. For the majority (10 of 13) of vitamins (vitamin A, vitamin E, vitamin K, thiamin, riboflavin, vitamin B-6, vitamin B-12, niacin, biotin, and vitamin C), intake from usual and fortified food already reached or exceeded 80% of the recommended dietary allowances in all age groups. In the case of folate and pantothenic acid, intake from supplements was necessary to achieve at least 80% of recommended dietary allowances for half of the age groups, especially in females. Supplements with vitamin D considerably helped increase vitamin intake but failed to achieve 80% of references in almost all age groups. Intakes of vitamin A and folic acid exceeded the tolerable upper level most frequently in many age groups and were most pronounced in up to 32% and 13% of children aged 2-3 y. Intake of vitamin D, vitamin E, and vitamin C exceeded the tolerable upper level in single age groups only (<7% of subjects). For the other vitamins, no exceeded limits were identified. The ubiquitous availability of supplements might indicate that even healthy children and adolescents profit by taking them. However, it is difficult to evaluate whether consumers receive more benefits or risks from the unrestricted consumption of supplements as they are marketed today.  相似文献   

20.
OBJECTIVE: To determine vitamin C intakes among adults and to identify differences in dietary intake associated with vitamin C consumption. DESIGN: This cross-sectional study compared vitamin C intake, nutrient intake, and food group choices of adults with low (<30 mg/d), marginal (30-60 mg/d), and desirable (>60 mg/d) vitamin C intakes. SUBJECTS: Data from 2472 men and 2334 women aged 25-75 y were obtained from the 1994-1996 Continuing Survey of Food Intakes by Individuals (CSFII). RESULTS: Overall, 18% of the sample had low vitamin C intakes, 24% had marginal intakes, and 58% had desirable intakes. In addition to consuming less vitamin C, adults with low vitamin C intakes consumed significantly less (P相似文献   

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