山东临沂市254名农村婴幼儿血清视黄醇和类胡萝卜素水平及其与相关膳食因素的关系

目的为了解农村婴幼儿血清维生素A(VA)营养状况和血清类胡萝卜素水平,以及两者关系和相关影响因素而开展本研究。方法采用整群抽样方法,对山东省临沂市某镇辖区内254名6～24月龄健康婴幼儿进行健康体检和喂养状况调查。采集足背静脉血样,用高效液相色谱法测定血清视黄醇和β-胡萝卜素、α-胡萝卜素、β-隐黄素及叶黄素+玉米黄素含量。用膳食频率法回顾性调查婴幼儿最近一个月内的各类食物摄入状况,分析喂养状况与血清视黄醇和类胡萝卜素水平的关系。结果被调查婴幼儿血清视黄醇浓度平均为(0.96±0.55)μmol/L,不同月龄段间没有明显差异(P>0.05);血清VA缺乏率为40.6%,边缘性VA缺乏率为32.6%。血清β-胡萝卜素、α-胡萝卜素、β-隐黄素和叶黄素+玉米黄素浓度的平均值分别为(0.056±0.088)μmol/L、(3.3±12.1)nmol/L、(27.0±45.2)nmol/L和(0.22±0.22)μmol/L。不同月龄段儿童血清叶黄素+玉米黄素浓度存在差异(P<0.05),13～18月龄段低于6～12月龄儿童。母乳喂养和配方奶粉是影响婴幼儿血清视黄醇和β-胡萝卜素水平的主要因素。母乳喂养频率与β-胡萝卜素水平呈负相关(P<0.05),而配方粉喂养频率与血清视黄醇和除α-胡萝卜素以外的类胡萝卜素水平呈正相关(均为P<0.05);水果蔬菜喂养频率则只与血清β-胡萝卜素、α-胡萝卜素和β-隐黄素浓度呈正相关。血清视黄醇与类胡萝卜素各组分,以及类胡萝卜素各组分之间,具有显著正相关关系(均为P<0.001)。结论调查的农村婴幼儿血清VA营养状况较差,血清β-胡萝卜素、α-胡萝卜素、β-隐黄素及叶黄素+玉米黄素浓度与母乳、配方奶粉、水果蔬菜添加等喂养状况关系密切。     

Lutein and zeaxanthin concentrations in plasma after dietary supplementation with egg yolk.

BACKGROUND: The food matrix in which carotenoids are found affects their bioavailability. Lutein and zeaxanthin are abundant in egg yolks and accumulate in the macular region of the retina, where they may affect visual function. OBJECTIVE: We sought to determine whether plasma lutein and zeaxanthin concentrations are elevated after dietary supplementation with egg yolk. DESIGN: Eleven moderately hypercholesterolemic men and women consumed 2 separate baseline diets, which contained 29-33% of energy as total fat, with 20% of energy as either beef tallow or corn oil. These diets were supplemented with cooked chicken egg yolks (1.3 egg yolks/d for an intake of 10.4 MJ). Each subject consumed all 4 diets. Each diet was consumed for 4.5 wk, with a washout period of >/=2 wk between diet phases. At the end of each diet phase, fasting morning plasma samples were collected and stored for carotenoid analysis by HPLC. Commercial chicken egg yolks were analyzed for carotenoids and cholesterol. RESULTS: Egg yolk supplementation of the beef tallow diet increased plasma lutein by 28% (P < 0.05) and zeaxanthin by 142% (P < 0.001); supplementation of the corn oil diet increased plasma lutein by 50% (P < 0.05) and zeaxanthin by 114% (P < 0.001). Changes in plasma lycopene and beta-carotene were variable, with no consistent trend. Egg yolk supplementation increased plasma LDL-cholesterol concentrations by 8-11% (P < 0.05). CONCLUSIONS: Egg yolk is a highly bioavailable source of lutein and zeaxanthin. The benefit of introducing these carotenoids into the diet with egg yolk is counterbalanced by potential LDL-cholesterol elevation from the added dietary cholesterol.     

Low-serum carotenoid concentrations and carotenoid interactions predict mortality in US adults: the Third National Health and Nutrition Examination Survey

Evidence regarding the health benefits of carotenoids is controversial. Effects of serum carotenoids and their interactions on mortality have not been examined in a representative sample of US adults. The objective was to examine whether serum carotenoid concentrations predict mortality among US adults. The study consisted of adults aged ≥20 years enrolled in the Third National Health and Nutrition Examination Survey, 1988 to 1994, with measured serum carotenoids and mortality follow-up through 2006 (N = 13 293). Outcomes were all-cause, cardiovascular disease, and cancer mortality. In adjusted Cox proportional hazards models, participants in the lowest total carotenoid quartile (<1.01 μmol/L) had significantly higher all-cause mortality (mortality rate ratio, 1.38; 95% confidence interval, 1.15-1.65; P = .005) than those in the highest total carotenoid quartile (>1.75 μmol/L). For α-carotene, the highest quartile (>0.11 μmol/L) had the lowest all-cause mortality rates (P < .001). For lycopene, the middle 2 quartiles (0.29-0.58 μmol/L) had the lowest all-cause mortality rates (P = .047). Analyses with continuous carotenoids confirmed associations of serum total carotenoids, α-carotene, and lycopene with all-cause mortality (P < .001). In a random survival forest analysis, very low lycopene was the carotenoid most strongly predictive of all-cause mortality, followed by very low total carotenoids. α-Carotene/β-cryptoxanthin, α-carotene/lutein+zeaxanthin and lycopene/lutein+zeaxanthin interactions were significantly related to all-cause mortality (P < .05). Low α-carotene was the only carotenoid associated with cardiovascular disease mortality (P = .002). No carotenoids were significantly associated with cancer mortality. Very low serum total carotenoid, α-carotene, and lycopene concentrations may be risk factors for mortality, but carotenoids show interaction effects on mortality. Interventions of balanced carotenoid combinations are needed for confirmation.     

城乡社区成人不同季节血清类胡萝卜素水平

目的测定部分城乡成年居民血清中类胡萝卜素的浓度。方法从三个不同类型的社区中,选择184人30～60岁成人(男性84,女100)作为被调查对象,分别于夏、秋、冬、春四个季节时采集每个受试者的空腹静脉血,用HPLC测定血清中β-胡萝卜素、α-胡萝卜素、β-隐黄质、番茄红素、叶黄素类(叶黄素和玉米黄质)五种类胡萝卜素的含量。结果被调查者四个季节的血清中,五种类胡萝卜素的平均浓度(μmol/L)为:β-胡萝卜素0.72±0.20,0.71±0.18,0.70±0.19和0.63±0.20,α-胡萝卜素0.037±0.018,0.039±0.015,0.038±0.017和0.030±0.019,β-隐黄质0.11±0.03,0.14±0.03,0.13±0.04和0.10±0.03,叶黄素和玉米黄素0.61±0.16,0.45±0.09,0.46±0.12和0.47±0.14,番茄红素:0.43±0.26,0.11±0.06,0.07±0.04和0.07±0.03。春季时血清β-胡萝卜素明显低于其他三个季节,但其中城市中心社区居民的血清β-胡萝卜素浓度没有明显季节变化。血清α-胡萝卜素、β-隐黄质、叶黄素和玉米黄素、番茄红素浓度都有着显著的季节变化。三类居民间在每个季节、每一种类胡萝卜素成分的血清平均浓度都有显著差别。结论本文报告了184名中国成年居民夏、秋、冬、春四个季节713份血清中类胡萝卜素摄入量数据,为了解部分人群的血液类胡萝卜素分布提供资料。     

Retinol, β-carotene,and lutein + zeaxanthin in the milk of Brazilian nursing women: associations with plasma concentrations and influences of maternal characteristics

The objectives of the present study were to determine the concentration of vitamin A (retinol), provitamin A (β-carotene), and non–provitamin A (lutein + zeaxanthin) carotenoids in mature breast milk of Brazilian women (n = 49; 30-120 days postpartum), and to evaluate their associations with plasma levels and with maternal characteristics (parity and body mass index). Nutrient concentrations (mean ± SE) in plasma and milk were, respectively, as follows: retinol, 2.5 ± 0.1 and 1.4 ± 0.1 μmol/L; β-carotene, 0.3 ± 0.04 and 0.018 ± 0.002 μmol/L; lutein + zeaxanthin, 0.06 ± 0.01 and 0.006 ± 0.001 μmol/L. The milk/plasma molar ratio was 10 times higher for retinol than for carotenoids, and twice as high for the more polar xanthophylls (lutein + zeaxanthin) than for the less polar β-carotene. Associations (P < .05) between milk and plasma levels were observed for β-carotene (r = 0.35) and lutein + zeaxanthin (r = 0.37), but not for retinol. Multiparous women presented higher (P < .05) levels of retinol in plasma and in milk than primiparous women. Plasma levels of retinol, β-carotene, and lutein + zeaxanthin, but not milk levels, were significantly associated with body mass index (r = 0.32, 0.45, and 0.41, respectively).     

Food Predictors of Plasma Carotenoids

Empirical prediction models that weight food frequency questionnaire (FFQ) food items by their relation to nutrient biomarker concentrations may estimate nutrient exposure better than nutrient intakes derived from food composition databases. Carotenoids may especially benefit because contributing foods vary in bioavailability and assessment validity. Our objective was to develop empirical prediction models for the major plasma carotenoids and total carotenoids and evaluate their validity compared with dietary intakes calculated from standard food composition tables. 4180 nonsmoking women in the Nurses’ Health Study (NHS) blood subcohort with previously measured plasma carotenoids were randomly divided into training (n = 2787) and testing (n = 1393) subsets. Empirical prediction models were developed in the training subset by stepwise selection from foods contributing ≥0.5% to intake of the relevant carotenoid. Spearman correlations between predicted and measured plasma concentrations were compared to Spearman correlations between dietary intake and measured plasma concentrations for each carotenoid. Three to 12 foods were selected for the α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin, lycopene, and total carotenoids prediction models. In the testing subset, Spearman correlations with measured plasma concentrations for the calculated dietary intakes and predicted plasma concentrations, respectively, were 0.31 and 0.37 for α-carotene, 0.29 and 0.31 for β-carotene, 0.36 and 0.41 for β-cryptoxanthin, 0.28 and 0.31 for lutein/zeaxanthin, 0.22 and 0.23 for lycopene, and 0.22 and 0.27 for total carotenoids. Empirical prediction models may modestly improve assessment of some carotenoids, particularly α-carotene and β-cryptoxanthin.     

Tocopherol and carotenoid contents of selected Korean fruits and vegetables

The tocopherol (α-, γ-, and δ-) and carotenoid (α-carotene, β-carotene, β-cryptoxanthin, lutein, zeaxanthin, and lycopene) contents of seven raw fruits and 14 raw or processed (cooked or fermented) vegetables commonly consumed by young children in Kwangju, Republic of Korea, were determined using reversed-phase HPLC. All samples were obtained from three different locations (households or local markets) in Kwangju during summer, 2005. All fruits and vegetables in this study had detectable quantities of α-tocopherol, while many had detectable quantities of γ- and δ-tocopherols. β-carotene was contained in all samples except cooked bracken. Except for sweet potato, all fruits and vegetables contained lutein. β-cryptoxanthin and lycopene were not detected in any of the cooked vegetables in this study. Also, none of the fermented vegetables (kimchi) had detectable levels of zeaxanthin and lycopene. The findings of this study may be valuable for use in Korean and other food composition databases.     

In vitro investigation of the bioaccessibility of carotenoids from raw,frozen and boiled red chili peppers (Capsicum annuum)

Background

Carotenoid-rich foods are associated with antioxidant activity and the ability to alleviate chronic diseases.

Purpose

The present study investigated the effect of processing on the content and bioaccessibility of carotenoids from 13 cultivars of red chili pepper (Capsicum annuum).

Methods

Carotenoids in chili peppers were analyzed before an in vitro digestion process. The portion of carotenoid transferred to the micelle fraction (bioaccessibility) was also quantified.

Results

β-Carotene, β-cryptoxanthin, capsanthin and antheraxanthin were the most abundant carotenoids. Zeaxanthin, violaxanthin, neoxanthin and lutein were detected at lower concentrations. In general, freezing and boiling reduced carotenoid contents. Capsanthin and zeaxanthin had the highest bioaccessibility at an average value from 36 to 40 %, followed by antheraxanthin (26 %). Bioaccessibility of β-cryptoxanthin, violaxanthin and β-carotene was lower, averaging 6.1, 4.8 and 4.0 %, respectively. Neoxanthin and lutein were not detected in micelles. Freezing increased the bioaccessibility of capsanthin, zeaxanthin, antheraxanthin, β-cryptoxanthin and violaxanthin; β-cryptoxanthin bioaccessibility increased and capsanthin and zeaxanthin bioaccessibility decreased following boiling.

Conclusions

Differences in the contents and bioaccessibility of carotenoids in 13 C. annuum cultivars and between the processed methods were herein evidenced.     

A 12-wk egg intervention increases serum zeaxanthin and macular pigment optical density in women

Two carotenoids found in egg yolk, lutein and zeaxanthin, accumulate in the macular retina where they may reduce photostress. Increases in serum lutein and zeaxanthin were observed in previous egg interventions, but no study measured macular carotenoids. The objective of this project was to determine whether increased consumption of eggs would increase retinal lutein and zeaxanthin, or macular pigment. Twenty-four females, between 24 and 59 y, were assigned to a pill treatment (PILL) or 1 of 2 egg treatments for 12 wk. Individuals in the PILL treatment consumed 1 sugar-filled capsule/d. Individuals in the egg treatments consumed 6 eggs/wk, containing either 331 microg (EGG 1) or 964 microg (EGG 2) of lutein and zeaxanthin/yolk. Serum cholesterol, serum carotenoids, and macular pigment OD (MPOD) were measured at baseline and after 4, 8, and 12 wk of intervention. Serum cholesterol concentrations did not change in either egg treatment group, but total cholesterol (P = 0.04) and triglycerides (P = 0.02) increased in the PILL group. Serum zeaxanthin, but not serum lutein, increased in both the EGG 1 (P = 0.04) and EGG 2 (P = 0.01) groups. Likewise, MPOD increased in both the EGG 1 (P = 0.001) and EGG 2 (P = 0.049) groups. Although the aggregate concentration of carotenoid in 1 egg yolk may be modest relative to other sources, such as spinach, their bioavailability to the retina appears to be high. Increasing egg consumption to 6 eggs/wk may be an effective method to increase MPOD.     

Development of an Austrian Carotenoid Database

Due to the increasing interest in food carotenoids an Austrian Carotenoid Database was established. This study focused on two aspects: first, the establishment of a robust analysis method, and second, the sampling. The analysis method, was adapted from a standard procedure which was established during a European EC MAT project. To obtain a valuable average the sampling of the vegetables was done in three different climatic regions in Austria (north-east, south-east, west) in the years 1997 and 1998. The result of this study is a valuable database of the main carotenoids (lutein, zeaxanthin, β -cryptoxanthin, lycopene, α -carotene and β -carotene) in Austrian vegetables.     

Multinational study of major breast milk carotenoids of healthy mothers

Summary. Background: Carotenoids in serum vary between countries and within populations with evidence suggesting a qualitative relationship to diet. Breast milk carotenoids furnish a source of vitamin A and potentially provide immunoprotection and other health benefits for infants. There have been numerous studies of milk carotenoid concentrations in undernourished populations; however, carotenoid concentrations have not previously been compared in populations of well-nourished mothers. Aim of Study: To compare concentrations of five major carotenoid groups: α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin, and lycopene in breast milk of healthy women from Australia, Canada, Chile, China, Japan, Mexico, the Philippines, the United Kingdom, and the United States, and to qualitatively compare patterns of dietary intake with milk carotenoid concentrations. Methods: Breast milk collected from healthy lactating women was analyzed for concentrations of five carotenoids and retinol and quantitated relative to total milk lipid. All determinations were performed in a single research laboratory using standardized methodology. Mothers consumed their usual diets and provided a single 24-h dietary recall. Results: Breast milk carotenoid concentrations varied greatly among countries, with the greatest differences in β-cryptoxanthin (∼ 9-fold) and the least in α-carotene and lycopene (∼ 3-fold). Breast milk retinol concentrations varied ∼ 2-fold across countries. The provitamin A carotenoids α-carotene, β-carotene, and β-cryptoxanthin as a group accounted for > 50 % of the carotenoids measured. Total breast milk carotenoids were highest in Japanese and lowest in Philippine mothers. Breast milk β-carotene concentrations were highest in Chile and lowest in the Philippines. Conclusions: Patterns of breast milk carotenoids were unique to each country and qualitative patterns reflected the dietary carotenoid supply. Received: 24 June 2002, Accepted: 12 December 2002 Supported by a grant from Wyeth Nutrition, Philadelphia, PA, USA. Correspondence to: Louise M. Canfield     

Dietary, anthropometric, and lifestyle correlates of serum carotenoids in postmenopausal women

Purpose

Concentration of carotenoids in the serum is a biomarker of mainly vegetable and fruit consumption. However, the levels of carotenoids in humans may decline with age and can also depend on body fat, alcohol consumption, and cigarette smoking.

Method

Food intake and characteristics of 159 randomly chosen women aged 56–75 years were obtained by a self-administered questionnaire. Serum concentrations of carotenoids were determined by high-performance liquid chromatography. Estimation of fat mass was carried out by dual energy X-ray absorptiometry.

Results

The estimated total daily intake of carotenoids was 9.75 mg: α-carotene 10.6 %; β-carotene 35.6 %; lutein/zeaxanthin 27.1 %; β-cryptoxanthin 4.7 %; and lycopene 22.0 %. We observed statistically significant positive correlations between concentrations of serum carotenoids and their estimated intakes (r = 0.11 lycopene to 0.38 β-carotene) and fruit and vegetable intake (r = 0.15 lycopene to 0.30 β-carotene). Concentration of serum carotenoids positively correlated with education (r = 0.17 α-carotene to 0.29 lycopene) and alcohol intake (r = 0.02 α-carotene to r = 0.25 lycopene). Inverse correlations were with the age (r = ?0.18 α-carotene to ?0.42 lycopene) and fat mass (r = ?0.15 lycopene to ?0.29 α-, β-carotene).

Conclusion

In this population of healthy postmenopausal women, serum concentrations of carotenoids declined with increasing age and body fat mass. The concentrations were increased among women with high vegetable and fruit consumption, moderate alcohol intake, and high level of education.     

Serum carotenoids and pulmonary function in older community-dwelling women

Background and Objectives

Deterioration in pulmonary function is associated with greater disability and mortality in older adults. Dietary antioxidants are implicated in lung health, but the relationship between major dietary antioxidants, such as serum carotenoids, and pulmonary function have not been well characterized. Serum carotenoids are considered the most reliable indicator of fruit and vegetable intake.

Subjects and Methods

We examined the relationship between serum ??-carotene, ??-carotene, ??-cryptoxanthin, lutein/zeaxanthin, and lycopene with pulmonary function (forced expiratory volume in one second [FEV₁] and forced vital capacity [FVC]) in a population-based sample of 631 moderately to severely disabled community-dwelling older women (Women??s Health and Aging Study I) in Baltimore, Maryland, USA.

Results

Higher serum ??-carotene and ??-carotene concentrations were positively associated with both FEV₁ and FVC, respectively (all P < 0.05), in separate multivariate linear regression models adjusting for age, race, education, cognition, anemia, inflammation, and chronic diseases. Total serum carotenoids were associated with FEV1 (P = 0.08) and FVC (P = 0.06), respectively, in similar models. No association was found between ??-cryptoxanthin, lutein/zeaxanthin, and lycopene, and FEV₁ or FVC.

Conclusions

Higher serum ??-carotene and ??-carotene concentrations, which reflect greater intake of orange and dark green leafy fruits and vegetables, were associated with better pulmonary function among older community-dwelling women.function may lead to food avoidance and to a higher incidence of digestive complaints.     

Serum Carotenoid and Tocopherol Concentrations Vary by Dietary Pattern among African Americans

Background

Intakes and biochemical concentrations of carotenoids and tocopherols have been associated with chronic diseases.

Objective

To describe dietary patterns in Jackson Heart Study participants and to determine if biochemical measurements of antioxidants differ across these.

Design

Cross-sectional analysis of data for 373 African-American men and women (age 35 to 80 years), participating in the Diet and Physical Activity Substudy of the Jackson Heart Study.

Methods

Dietary intake was assessed with a region specific food frequency questionnaire. Patterns were defined by cluster analysis of food groups, as percent of energy intake.

Results

Four dietary patterns were identified: fast food, Southern, prudent, and juice. Individuals in the fast-food pattern (n=153) had significantly lower serum concentrations of lutein plus zeaxanthin and β-cryptoxanthin; those in the Southern cluster (n=99) had significantly lower serum α-carotene; and those in the prudent (n=63) and juice (n=58) clusters had significantly higher serum α-carotene and β-cryptoxanthin (P<0.05) relative to those in at least one other cluster (all P<0.05). The juice cluster also had higher serum α-tocopherol concentrations relative to the fast-food cluster.

Conclusions

Diets high in fast foods, snacks, soft drinks, and meat were associated with relatively low concentrations of carotenoids and α-tocopherol. This pattern contained the largest number of participants, and could contribute to the extensive health disparities seen in this region.     

Consumption of one egg per day increases serum lutein and zeaxanthin concentrations in older adults without altering serum lipid and lipoprotein cholesterol concentrations

Lutein and zeaxanthin accumulate in the macular pigment of the retina, and are reported to be associated with a reduced incidence of age-related macular degeneration. A rich source of lutein and zeaxanthin in the American diet is the yolk of chicken eggs. Thus, the objective of the study was to investigate the effect of consuming 1 egg/d for 5 wk on the serum concentrations of lutein, zeaxanthin, lipids, and lipoprotein cholesterol in individuals >60 y of age. In a randomized cross-over design, 33 men and women participated in the 18-wk study, which included one run-in and one washout period of no eggs prior to and between two 5-wk interventions of either consuming 1 egg or egg substitute/d. Serum lutein 26% (P < 0.001) and zeaxanthin 38% (P < 0.001) concentrations increased after 5-wk of 1 egg/d compared with the phase prior to consuming eggs. Serum concentrations of total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides were not affected. These findings indicate that in older adults, 5 wk of consuming 1 egg/d significantly increases serum lutein and zeaxanthin concentrations without elevating serum lipids and lipoprotein cholesterol concentrations.     

Plasma Carotenoids and Prostate Cancer: A Population-Based Case-Control Study in Arkansas

Carotenoids possess antioxidant properties and thus may protect against prostate cancer. Epidemiological studies of dietary carotenoids and this malignancy were inconsistent, partially due to dietary assessment error. In this study, we aimed to investigate the relation between plasma concentrations of carotenoids and the risk of prostate cancer in a population-based case-control study in Arkansas. Cases (n = 193) were men with prostate cancer diagnosed in 3 major hospitals, and controls (n = 197) were matched to cases by age, race, and county of residence. After adjustment for confounders, plasma levels of lycopene, lutein/zeaxanthin, and β -cryptoxanthin were inversely associated with prostate cancer risk. Subjects in the highest quartile of plasma lycopene (513.7 μ g/l) had a 55% lower risk of prostate cancer than those in the lowest quartile (140.5 μ g/l; P trend = 0.042). No apparent association was observed for plasma α -carotene and β -carotene. Further adjustment for the other 4 carotenoids did not materially alter the risk estimates for plasma lycopene, lutein/zeaxanthin, and β -cryptoxanthin but appeared to result in an elevated risk with high levels of plasma α -carotene and β -carotene. The results of all analyses did not vary substantially by age, race, and smoking status. This study added to the emerging evidence that high circulating levels of lycopene, lutein/zeaxanthin, and β -cryptoxanthin are associated with a low risk of prostate cancer.     

Updated Brazilian database on food carotenoids: Factors affecting carotenoid composition

This article updates the Brazilian database on food carotenoids. Emphasis is on carotenoids that have been demonstrated important to human health: α-carotene, β-carotene, β-cryptoxanthin, lycopene, lutein and zeaxanthin. The sampling and sample preparation strategies and the analytical methodology are presented. Possible sources of analytical errors, as well as the measures taken to avoid them, are discussed. Compositional variation due to such factors as variety/cultivar, stage of maturity, part of the plant utilized, climate or season and production technique are demonstrated. The effects of post-harvest handling, preparation, processing and storage of food on the carotenoid composition are also discussed. The importance of biodiversity is manifested by the variety of carotenoid sources and the higher levels of carotenoids in native, uncultivated or semi-cultivated fruits and vegetables in comparison to commercially produced crops.     

济宁市城乡社区成人四个季节膳食类胡萝卜素的摄入量

目的测定部分城乡成年居民膳食类胡萝卜素摄入量水平。方法从三个不同类型的社区中,选择184名30～60岁成人(男84,女100)作为被调查对象,采用"双份饭法"分别于夏、秋、冬、春四个季节收集被调查者连续3 d的全部膳食,用HPLC测定其中β-胡萝卜素、α-胡萝卜素、β-隐黄质、番茄红素、叶黄素和玉米黄质六种类胡萝卜素的含量。结果被调查者夏季膳食中β-胡萝卜素、α-胡萝卜素、β-隐黄质、番茄红素和叶黄素+玉米黄质的平均每日摄入量分别为2.48±2.71 mg、276.6±469.4μg、86.9±241.4μg、2.16±3.38 mg和1.48±1.65 mg;秋季分别为3.39±4.10 mg、271.7±462.8μg、339.9±1016.8μg、0.25±1.34 mg和2.07±3.00 mg;冬季分别为2.85±3.76 mg、302.7±622.6μg、108.8±142.3μg、0.36±1.46 mg和1.97±3.00 mg;春季分别为3.76±3.35mg、162.4±413.9μg、42.1±93.8μg、0.86±1.39 mg和6.10±6.26 mg。各种类胡萝卜素摄入量均随季节而变化,夏季摄入番茄红素较多,秋季摄入β-隐黄质较多,春季摄入叶黄素+玉米黄质较多,而β-胡萝卜素、α-胡萝卜素摄入量的季节波动较小。城市中心社区居民类胡萝卜素摄入量一般较高,城市周边社区和农村社区居民摄入量较低;农村社区居民只有春季叶黄素+玉米黄质摄入量高于城市中心社区居民。结论本研究报告了三种不同社区居民类胡萝卜素摄入量数据,为类胡萝卜素营养研究提供部分资料。     

A Fast,Reliable and Low-cost Saponification Protocol for Analysis of Carotenoids in Vegetables

Carotenoids are mainly present in vegetables and fruits and display several important biological actions (provitamin A, antioxidant and anticarcinogenic activities and immunomodulation). To assess the intake of carotenoids and their potential health benefits in humans, it is necessary to have reliable information about carotenoid content in food. Saponification is commonly used during analysis of carotenoids in vegetables and fruits to release esterified xanthophylls and to eliminate interfering substances. It is a time-consuming step and involves the use of considerable volumes of solvents in the partition. To reduce the time and costs of the saponification process, we compare the reliability of a “shortcut” (small volumes, vortex 3 min, 20% potassium hydroxide, hexane/methylene chloride extraction) with that of a “standard” protocol (stirring 30 min, 5% potassium hydroxide, petroleum ether/diethyl ether extraction twice plus washings). Accuracy and precision were assessed according to studies of certified reference materials for carotenoid analysis in foods. For lutein, zeaxanthin, α -cryptoxanthin, β -cryptoxanthin, lycopene, α -carotene andβ -carotene, the “shortcut” showed within-day and between-day variability similar to or lower than that of the “standard” protocol, comparable deviation from the assigned values and higher recovery for carotenes, especially for lycopene. Advantages of the “shortcut” include considerably reduced time, higher overall recoveries and lower solvent expenditure, resulting in a reduction in time and total cost of up to 80–90% without loss of accuracy or precision.     

Hyperglycemia and Carotenoid Intake Are Associated with Serum Carotenoids in Youth with Type 1 Diabetes

BackgroundSerum carotenoids are commonly used as biomarkers of fruit and vegetable (F/V) intake in the general population. Although hyperglycemia induces oxidative stress, it is unknown whether this pathway is associated with lower serum carotenoid concentrations in individuals with type 1 diabetes. Consequently, the utility of serum carotenoids as markers of F/V intake in individuals with type 1 diabetes is unclear.ObjectiveThe study objectives were: 1) to investigate the relationship of glycemic control, oxidative stress, dietary carotenoid and F/V intake with serum carotenoid concentrations in youth with type 1 diabetes and 2) to determine whether glycemic control or oxidative stress moderates the association of carotenoid and F/V intake with serum carotenoids.DesignThe study was a secondary analysis of baseline data from youth with type 1 diabetes. Blood samples were drawn from youth with type 1 diabetes to assess carotenoids and markers of glycemic control (glycated hemoglobin and 1,5-anhydroglucitol); urine samples were used to assess oxidative stress (8-iso-prostaglandin F_2α); and 3-day diet records completed by families were used to determine F/V and carotenoid intake.Participants/settingThe study participants were youth with type 1 diabetes (n=136; age range: 8 to 16.9 years; diabetes duration ≥1 year; glycated hemoglobin: 5.8% to 11.9%) enrolled in a nutrition intervention trial from 2010 to 2013 at a tertiary diabetes center in Boston, MA.Main outcome measuresSerum carotenoids (total carotenoids and α-carotene, β-carotene, lycopene, β-cryptoxanthin, and lutein+zeaxanthin).Statistical analysisRegression analyses were used to estimate the association of glycemic control, oxidative stress, F/V and carotenoid intake with serum carotenoids, as well as the role of glycemic control and oxidative stress in moderating diet-serum carotenoid associations.ResultsGreater F/V intake (β=0.35, P<0.001) and carotenoid intake (β=0.28, P<0.01) were associated with higher total serum carotenoids, and no moderation by glycemic control or oxidative stress was observed. Greater hyperglycemia, as indicated by lower 1,5-anhydroglucitol (β=0.27, P<0.01), was related to lower serum carotenoids; however, glycated hemoglobin was not associated with serum carotenoids. 8-Iso-prostaglandin F2α was not associated with glycemic control or serum carotenoids.ConclusionsFindings support the validity of serum carotenoids as markers of F/V and carotenoid intake in youth with type 1 diabetes.