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PubMed2005

Relationship between plasma carotenoids and prostate cancer.

Carotenoids, particularly lycopene, are thought to decrease prostate cancer risk, but the relationship between plasma carotenoid concentrations and risk in various populations has not been well characterized. Comparing 118 non-Hispanic Caucasian men mainly from southeast Texas with nonmetastatic prostate cancer with 52 healthy men from the same area, we conducted a case-control analysis evaluating associations between risk and plasma levels of total carotenoids, beta-cryptoxanthin, alpha- and trans-beta-carotene, lutein and zeaxanthin, total lycopenes, trans-lycopene, total cis-lycopenes, and cis-lycopene isoforms 1, 2, 3, and 5. Risk for men with high plasma levels of alpha-carotene, trans-beta-carotene, beta-cryptoxanthin, and lutein and zeaxanthin was less than half that for those with lower levels. In contrast, we observed no significant associations for total lycopenes, all-trans-lycopene, and cis-lycopene isomer peaks 2, 3, and 5, although high levels of cis-lycopene isomer peak 1 were inversely associated with risk. Analysis of men with aggressive disease (Gleason scores of > or =7, n = 88) vs. less aggressive cases (Gleason scores of <7, n = 30) failed to reveal significant associations between carotenoid levels and the risk of diagnosis with aggressive disease. These findings suggest that, in these men, higher circulating levels of alpha-cryptoxanthin, alpha-carotene, trans-beta-carotene, and lutein and zeaxanthin may contribute to lower prostate cancer risk but not to disease progression.

Antioxidants↗
PubMedDate not supplied

Variations in serum carotenoid concentrations among United States adults by ethnicity and sex.

Increased fruit and vegetable intake is associated with a lower risk of heart disease and cancer. Carotenoids, which occur primarily in fruits and vegetables, have been associated with reduced risk of some chronic diseases. To examine the distribution of serum carotenoid concentrations among US adults by ethnicity and sex, the author used data from the Third National Health and Nutrition Examination Survey, conducted from 1988 to 1994. After exclusions, 14,914 participants aged > or =20 years who attended the medical examination clinic had their serum carotenoid concentrations determined. Mexican-American men had higher total concentrations than European Americans and African Americans. In general, European-American participants were characterized by high lycopene but low beta-cryptoxanthin and lutein/zeaxanthin concentrations; African Americans by high lutein/zeaxanthin and low alpha-carotene and beta-cryptoxanthin concentrations; and Mexican Americans by high alpha-carotene, beta-cryptoxanthin, and lutein/zeaxanthin concentrations. The implications of these different carotenoid concentration patterns for future risk of disease within the ethnic and sex groups remain to be clarified.

Adult↗
PubMed1983

Gastric cytoprotective effects of vitamin A and other carotenoids.

The effects of vitamin A and some carotenoids (beta-carotene, beta-cryptoxanthin, zeaxanthin, lutein, capsorubin, capsanthin, capsanthol and lycopene) were studied (a) on the development of acute gastric mucosal lesions produced by topical application of 0.6 M HCl and (b) on gastric secretion in 4-h pylorus-ligated rats. It was found (a) that vitamin A, beta-carotene, beta-cryptoxanthin, zeaxanthin and lutein significantly inhibited the development of gastric mucosal lesions produced by 0.6 M HCl, while capsorubin, capsanthin, capsanthol and lycopene failed to prevent the development of such lesions; and (b) that vitamin A, beta-carotene, beta-cryptoxanthin, zeaxanthin and lutein, i.e., the carotenoids which exerted a cytoprotective effect, had no inhibitory effect on gastric acid secretion in 4-h pylorus-ligated rats. The possible relationship between chemical structure and gastric cytoprotection is discussed.

Animals↗
PubMedDate not supplied

Serum micronutrients and the subsequent risk of cervical cancer in a population-based nested case-control study.

A nested case-control study was conducted in Washington County, MD, to determine whether low serum micronutrients are related to the subsequent risk of cervical cancer. Among the 15,161 women who donated blood for future cancer research during a serum collection campaign in 1974, 18 developed invasive cervical cancer and 32 developed carcinoma in situ during the period January 1975 through May 1990. For each of these 50 cases, two matched controls were selected from the same cohort. The frozen sera of the cases and their matched controls were analyzed for a number of nutrients. The mean serum levels of total carotenoids, alpha-carotene, beta-carotene, cryptoxanthin, and lycopene were lower among cases than they were among controls. When examined by tertiles, the risk of cervical cancer was significantly higher among women in the lower tertiles of total carotenoids (odds ratio 2.7; 95% confidence limit, 1.1-6.4), alpha-carotene (odds ratio, 3.1; 95% confidence limit, 1.3-7.6), and beta-carotene (odds ratio, 3.1; 95% confidence limit, 1.2-8.1) as compared to women in the upper tertiles and the trends were statistically significant. Cryptoxanthin was significantly associated with a lower risk of cervical cancer when examined as a continuous variable. Retinol, lutein, alpha- and gamma-tocopherol, and selenium were not related to cervical cancer risk. Smoking was also strongly associated with cervical cancer. These findings are suggestive of a protective role for total carotenoids, alpha-carotene and beta-carotene in cervical carcinogenesis and possibly for cryptoxanthin and lycopene as well.

Adult↗
PubMed1998

Associations of plasma carotenoid concentrations and dietary intake of specific carotenoids in samples of two prospective cohort studies using a new carotenoid database.

Diet-plasma carotenoid associations were examined in samples of women and men from each cohort in the Nurses' Health Study and the Health Professionals Follow-Up Study. In each sample, participants completed two self-administered food frequency questionnaires with at least a 1-year interval and provided a blood specimen preceding the second food frequency questionnaire. Carotenoid intakes were estimated from values for the five major carotenoids found in human plasma, specifically, alpha- and beta-carotene, beta-cryptoxanthin, lutein, and lycopene, using the United States Department of Agriculture-National Cancer Institute Carotenoid Database, as well as updated values for tomato products. Pearson correlation coefficients were calculated to compare diet-plasma correlations over time by sex after adjustment for recognized covariates. Among nonsmoking women (n = 162), the adjusted diet-plasma carotenoid associations were 0.48 for alpha-carotene, 0.27 for beta-carotene and lutein, 0.32 for beta-cryptoxanthin, and 0.21 for lycopene. Among nonsmoking men (n = 110), diet-plasma correlations were 0.47 for alpha-carotene and lycopene, 0.35 for beta-carotene, 0.43 for beta-cryptoxanthin, and 0.40 for lutein. Correlations between total fruit or vegetable intake and each plasma carotenoid level were not as high as any of the calculated carotenoid intake using the new database values. The correlations observed in this study indicate that the new carotenoid database provides valuable information on specific carotenoid intake and may be useful in epidemiological studies that attempt to account for associations between fruit or vegetable intake and disease.

Aged↗
PubMed1996

Effects of freezing and canning of papaya slices on their carotenoid composition.

An HPLC study of the carotenoid composition of fresh, frozen and canned papaya fruit slices was done. There were no qualitative differences between the carotenoid patterns of fresh and frozen papaya fruit slices (cultivar Sunrise). The major carotenoids found in papaya extracts were lycopene and carotenol fatty acid esters of beta-cryptoxanthin and beta-cryptoxanthin-5, 6-epoxide. Other xanthophylls detected were beta-cryptoxanthin, trans-zeaxanthin and cryptoflavin. It was possible to determine the quantitative losses of carotenoids in papaya slices as a result of the freezing process and frozen storage, since samples of these fruits were available before processing. The pigment pattern of the canned product showed lycopene as being a major pigment. Thermal treatment induced the degradation of carotenol fatty acid esters of xanthophylls. The freezing and canning processing of papaya slices led to significant decreases in the total carotenoids quantified by HPLC, with frozen female slices and canned samples showing lower amounts of pigments. Hunter colour values of frozen slices were similar to those of fresh papaya fruit slices.

Carotenoids↗
PubMed1998

[Carotenoid intake in the German National Food Consumption Survey].

In nutritional epidemiological studies high consumption of fruits and vegetables was shown to be an important preventive measure to reduce the risk of cancer, coronary heart disease, and cataracts. These effects cannot be explained completely and in a sufficient way by the intake of beta-carotene and vitamin C. Other carotenoids differing in their antioxidative and biological properties are also provided with fruits and vegetables in significant amounts. Because data for other carotenoids than beta-carotene are not considered in computerized German food database and food composition tables, representative carotenoid intake calculations for the German population are missing. Therefore a carotenoid database, containing alpha- and beta-carotene, lycopene, lutein/zeaxanthin, and cryptoxanthin values for different fruits, vegetables, and other carotenoid-containing foods, was developed. With this database the carotenoid intake of the German population--stratified by sex and age--was evaluated on the basis of the German National Food Consumption Survey (NVS). The mean total carotenoid intake amounts to 5.33 mg/day. The average intake lutein was 1.91 mg/day, beta-carotene intake amounts to 1.81 mg/day, lycopene intake was 1.28 mg/day, alpha-carotene intake was 0.29 mg/day, and cryptoxanthin intake was 0.05 mg/day. Tomatoes and tomato products provide most of the lycopene. Green salads and vegetables are the most important contributors of lutein in Germany. Zeaxanthin is mainly consumed with maize but also with spinach and other vegetables like cabbage; alpha- and beta-carotene are mainly consumed with carrots. Peppers, oranges, and orange-juice are the most important cryptoxanthin sources.

Antioxidants↗
PubMed1997

Plasma carotenoids in German children and adolescents.

UNLABELLED: Carotenoids are important antioxidants and precursors of vitamin A, but only few studies have been carried out on plasma carotenoid levels in paediatric age groups. Using high-performance liquid chromatography we analysed concentrations of four important carotenoids (alpha-carotene, beta-carotene, cryptoxanthin, lycopene) in 129 healthy German children and adolescents (81 boys, 48 girls; age 1-18 years). For all carotenoids analysed, no significant differences between girls and boys were found. alpha-Carotene values ranged from 0 mumol/l (below detection limits) to 0.73 mumol/l (0-395 micrograms/l), beta-carotene from 0.09 mumol/l to 2.68 mumol/l (48-1443 micrograms/l), lycopene from 0 mumol/l to 1.51 mumol/l (0-815 micrograms/l), and cryptoxanthin from 0 mumol/l to 0.30 mumol/l (0-164 micrograms/l), respectively. Data analyses according to age groups showed a tendency towards higher levels of alpha- and beta-carotene, and lower levels of lycopene in young children. These differences were significant when children younger than 4 years were compared with those above 8 and 12 years, respectively. The data presented may serve as reference values for studies on children with nutritional disorders and diseases associated with a risk of vitamin deficiencies. CONCLUSION: Carotenoids are important antioxidants and singlet oxygen scavengers. Plasma levels of alpha-carotene, beta-carotene, lycopene and cryptoxanthin were determined in 129 healthy German children and adolescents. Highest values were found for beta-carotene and lycopene.

Adolescent↗
PubMed2005

Simultaneous quantification of alpha-tocopherol and four major carotenoids in botanical materials by normal phase liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry.

A rapid and sensitive method for the simultaneous quantification of alpha-tocopherol, beta-carotene, beta-cryptoxanthin, lutein and zeaxanthin in botanical materials has been developed using normal phase liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry (NP-LC-APCI-MS/MS). A systematic extraction procedure for different botanical materials was described and the extraction solvents were matched with normal-phase LC requirement. Quantification was performed by using the external standards and standard calibration curves were linear between 35 and 8505 ng/mL for alpha-tocopherol, 64-15,552 ng/mL for beta-carotene, 40-9720 ng/mL for beta-cryptoxanthin, 70-17,010 ng/mL for lutein and 64-15,552 ng/mL for zeaxanthin with regression coefficient r2 > 0.9996. The limits of quantification (LOQ) were 35, 64, 40, 70 and 66 ng/mL for alpha-tocopherol, beta-carotene, beta-cryptoxanthin, lutein and zeaxanthin, respectively.

Atmospheric Pressure↗
PubMed2005

Determination of carotenoids and all-trans-retinol in fish eggs by liquid chromatography-electrospray ionization-tandem mass spectrometry.

A novel method was developed for the combined determination of carotenoids and retinoids in fish eggs, which incorporates prior analyte isolation using liquid-liquid partitioning to minimize analyte degradation, and fraction analysis using high-performance liquid chromatography-electrospray (positive)-quadrupole mass spectrometry (LC-ESI(+)-MS; SIM or MRM modes). Eggs from Chinook salmon (Oncorhynchus tshawytscha) were used as the model fish egg matrix. The methodology was assessed and validated for beta-carotene, lutein, zeaxanthin, and beta-cryptoxanthin (molecular ion radicals [M](+)), canthaxanthin and astaxanthin ([M+Na](+) adducts) and all-trans-retinol ([(M+H)-H(2)O](+)). Using replicate egg samples (n=5) spiked with beta-cryptoxanthin and beta-carotene before and after extraction, matrix-sourced ESI(+) enhancement was observed as evidenced by comparable %matrix effect and %process efficiency values for beta-cryptoxanthin and beta-carotene of 114-119%. In aquaculture-raised eggs from adult Chinook salmon astaxanthin, all-trans-retinol, lutein and canthaxanthin were identified and determined at concentrations of 4.12, 1.06, 0.12 and 0.45 microg/g (egg wet weight), respectively. To our knowledge, this is the first report on a method for LC-MS determination of carotenoids and retinoids in a fish egg matrix, and the first carotenoid-specific determination in any fish egg sample.

Animals↗
PubMed1988

Liquid chromatographic profiles of major carotenoid esters in commercially processed California Navel and Valencia orange juice concentrates.

A procedure for establishing profiles of major carotenoid esters in commercially processed Valencia and Navel orange juice concentrates by reversed-phase liquid chromatography (LC) using Sudan 1 as internal standard is described. The procedure involved conversion of 5,6-epoxides in heat concentrated citrus juices to more stable 5,8-epoxides by treatment of extracted carotenoids with hydrochloric acid followed by dual wavelength analyses at 400 and 465 nm using LC. The esters of 5,8-furanoids (auroxanthin and mutatoxanthin) were approximately quantitated at 400 nm without interference from other carotenoids. Cryptoxanthin esters and free cryptoxanthin, lutein esters, citraurin esters and carotenes were approximately quantitated at 465 nm without interference from auroxanthin esters. The furanoid esters varied from 60 to 75% of the total carotenoids in the concentrates. The cryptoxanthin esters varied from 5 to 10% of the total carotenoids in Valencia orange juice concentrates and from 10 to 15% of the total carotenoids in Navel orange juice concentrates. Citraurin esters were present only in Navel orange juice concentrates and beta-carotene content was less than 5% of the total carotenoids in both concentrates. The total carotenoids and individual carotenoids increased with the advance in season in Navel orange juice concentrates which had less than half the amount of total carotenoids of Valencia orange juice concentrates.

Beverages↗
PubMed2005

Plasma carotenoids as biomarkers of intake of fruits and vegetables: ecological-level correlations in the European Prospective Investigation into Cancer and Nutrition (EPIC).

OBJECTIVE: The aim of this study was to assess the ability of a single 24-h dietary recall (24HDR) and food questionnaires (FQ) to predict plasma carotenoid levels at the ecological level by assessing the relationship between mean plasma carotenoid levels and mean intake of fruit and vegetables measured by 24HDR and FQ across 16 European regions. DESIGN: A random subsample of 3089 subjects was included, stratified by age and gender. They provided blood samples and dietary information between 1992 and 2000 as part of the European Prospective Investigation into Cancer and Nutrition. RESULTS: Using Spearman's correlation coefficients, the correlations between mean regional 24HDR fruit and vegetable variables and corresponding mean plasma carotenoid levels were generally higher than the correlations using FQ means. The highest correlation was between the 24HDR citrus fruit variable and beta-cryptoxanthin (r = 0.90). For 24HDR, total fruits and vegetables were highly correlated with lutein, zeaxanthin, and beta-cryptoxanthin (r = 0.83-0.87), while vegetables were more closely related with lutein (r = 0.69) and zeaxanthin (r = 0.68), and fruits correlated with zeaxanthin (r = 0.87) and beta-cryptoxanthin (r = 0.84). Root vegetables (r = 0.81) and total carrots (r = 0.71) were well correlated with alpha-carotene. In the multivariate models adjusting for age, body mass index, and season, and using observations of means stratified by sex and region, the association was generally higher for 24HDR compared to FQ. CONCLUSION: Mean regional intakes of fruits and vegetables in several European countries were closely correlated with corresponding mean plasma levels of individual carotenoids. Fruits and vegetables measured by 24HDR were generally better able to predict plasma carotenoids at the ecological level.

Antioxidants↗
PubMed2001

Are retinol, vitamin C, vitamin E, folate and carotenoids intake associated with bladder cancer risk? Results from the Netherlands Cohort Study.

In the Netherlands Cohort Study among 120 852 subjects aged 55-69 years at baseline (1986), the association between vitamins and carotenoids intake, vitamin supplement use, and bladder cancer incidence was examined. Exposure status was measured with a food-frequency questionnaire. After 6.3 years of follow-up, data from 569 cases and 3123 subcohort members were available for case-cohort analyses. The age-, sex-, and smoking-adjusted relative risks (RRs) for retinol, vitamin E, folate, a-carotene, b-carotene, lutein and zeaxanthin, and lycopene were 1.04, 0.98, 1.03, 0.99, 1.16, 1.11, and 1.08, respectively, comparing highest to lowest quintile of intake. Only vitamin C (RR: 0.81, 95% CI: 0.61-1.07, P-trend = 0.08), and b-cryptoxanthin intake (RR: 0.74, 95% CI: 0.53-1.03, P-trend < 0.01) were inversely associated with bladder cancer risk. The association with vitamin C disappeared after adjustment for b-cryptoxanthin but not vice versa. The RRs for supplemental use of vitamin A, C or E compared to no use were around unity. We conclude that dietary or supplemental intake of vitamin A, vitamin C, vitamin E, and intake of folate, and most carotenoids are not associated with bladder cancer. In this study, only b-cryptoxanthin intake appeared to be inversely associated.

Aged↗
PubMed2001

Serum concentrations of carotenoids and vitamins A, E, and C in control subjects from five European countries.

High intakes of fruits and vegetables, or high circulating levels of their biomarkers (carotenoids, vitamins C and E), have been associated with a relatively low incidence of cardiovascular disease, cataract and cancer. Exposure to a high fruit and vegetable diet increases antioxidant concentrations in blood and body tissues, and potentially protects against oxidative damage to cells and tissues. This paper describes blood concentrations of carotenoids, tocopherols, ascorbic acid and retinol in well-defined groups of healthy, non-smokers, aged 25-45 years, 175 men and 174 women from five European countries (France, UK (Northern Ireland), Republic of Ireland, The Netherlands and Spain). Analysis was centralised and performed within 18 months. Within-gender, vitamin C showed no significant differences between centres. Females in France, Republic of Ireland and Spain had significantly higher plasma vitamin C concentrations than their male counterparts. Serum retinol and alpha-tocopherol levels were similar between centres, but gamma-tocopherol showed a great variability being the lowest in Spain and France, and the highest in The Netherlands. The provitamin A: non-provitamin A carotenoid ratio was similar among countries, whereas the xanthophylls (lutein, zeaxanthin, beta-cryptoxanthin) to carotenes (alpha-carotene, beta-carotene, lycopene) ratio was double in southern (Spain) compared to the northern areas (Northern Ireland and Republic of Ireland). Serum concentrations of lutein and zeaxanthin were highest in France and Spain; beta-cryptoxanthin was highest in Spain and The Netherlands; trans-lycopene tended to be highest in Irish males and lowest in Spanish males; alpha-carotene and beta-carotene were higher in the French volunteers. Due to the study design, the concentrations of carotenoids and vitamins A, C and E represent physiological ranges achievable by dietary means and may be considered as 'reference values' in serum of healthy, non-smoking middle-aged subjects from five European countries. The results suggest that lutein (and zeaxanthin), beta-cryptoxanthin, total xanthophylls and gamma-tocopherol (and alpha- : gamma-tocopherol) may be important markers related to the healthy or protective effects of the Mediterranean-like diet.

Adult↗
PubMed2002

The intake of carotenoids in an older Australian population: The Blue Mountains Eye Study.

OBJECTIVE: To describe the distribution of carotenoid intakes and important food sources of carotenoids in the diet of a representative population of older Australians. DESIGN: Population-based cohort study. SETTING: Two post-code areas in the Blue Mountains, west of Sydney, Australia. SUBJECTS: We studied 2012 (86%) of the 2334 participants aged 55+ years attending the 5-year follow-up of the cross-sectional Blue Mountains Eye Study (BMES), who completed a detailed semi-quantitative food-frequency questionnaire. The intakes for five carotenoids were studied: alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein and zeaxanthin combined, and lycopene. RESULTS: The mean intake per day for each carotenoid was: alpha-carotene, 2675 microg; beta carotene equivalents, 7301 microg; beta-cryptoxanthin, 299 microg; lutein and zeaxanthin, 914 microg; lycopene, 3741 microg; retinol, 653 microg; total vitamin A, 1872 microg retinol equivalents. beta-Carotene equivalents contribute a substantial proportion of total vitamin A intake (65%) in this population. Women had slightly higher intakes than men for alpha-carotene, beta-carotene equivalents, and lutein and zeaxanthin (P < 0.05). Carrots and pumpkin were the main contributors to alpha-carotene and beta-carotene equivalent intakes. Orange juice, oranges and papaw were the main contributors to beta-cryptoxanthin intake. Broccoli, green beans and oranges contributed substantially to lutein and zeaxanthin intake. The main contributors to lycopene intake were tomatoes and bolognaise sauce. CONCLUSIONS: Vitamin A intake in this population is high relative to the Australian Recommended Dietary Intake. Carotenoid intakes, particularly beta-carotene, make a substantial contribution, particularly from fruit and vegetables. This study provides important information as a basis for examining associations between dietary carotenoid intake and eye disease in the BMES.

Carotenoids↗
PubMed1990

Effects of carotenoids on aflatoxin B1-induced mutagenesis in S. typhimurium TA 100 and TA 98.

The effects of beta-carotene, canthaxanthin, and extracts of tomato paste (containing lycopene) and orange juice (containing cryptoxanthin) on aflatoxin B1 (AFB1)-induced mutagenesis in S. typhimurium TA 100 and TA 98 were investigated. Inhibition of mutagenesis was studied during and following completion of AFB1 metabolism (i.e., after the addition of menadione), thereby permitting separate examination of the metabolic activation and phenotypic expression phases. Each experimental carotenoid, except lycopene, inhibited AFB1-induced mutagenesis in both tester strains. Cryptoxanthin was the most potent inhibitor, being at least an order of magnitude more potent than the other carotenoids. Inhibition by beta-carotene and canthaxanthin was more prominent during the activation phase, whereas cryptoxanthin was more effective during the subsequent phenotypic expression phase. These inhibitory effects were not dependent on conversion to retinol.

Aflatoxins↗
PubMed2001

Serum carotenoids and breast cancer.

The consumption of vegetables and fruit may protect against many types of cancer, but research evidence is not compelling for breast cancer. Carotenoids are pigments that are present in most plants and have known antioxidant properties. Blood concentrations of carotenoids have been proposed as integrated biochemical markers of vegetable, fruit, and synthetic supplements consumed. In a case-control study (270 cases, 270 controls) nested within a cohort in New York during 1985-1994, the carotenoids lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, and beta-carotene were measured in archived serum samples using liquid chromatography. There was an evident increase in the risk of breast cancer for decreasing beta-carotene, lutein, alpha-carotene, and beta-cryptoxanthin. The risk of breast cancer approximately doubled among subjects with blood levels of beta-carotene at the lowest quartile, as compared with those at the highest quartile (odds ratio = 2.21; 95% confidence interval (CI): 1.29, 3.79). The risk associated with the other carotenoids was similar, varying between 2.08 (95% CI: 1.11, 3.90) for lutein and 1.68 (95% CI: 0.99, 2.86) for beta-cryptoxanthin. The odds ratio for the lower quartile of total carotenoids was 2.31 (95% CI: 1.35, 3.96). These observations offer evidence that a low intake of carotenoids, through poor diet and/or lack of vitamin supplementation, may be associated with increased risk of breast cancer and may have public health relevance for people with markedly low intakes.

Adult↗
PubMed2005

An approach to estimate between- and within-group correlation coefficients in multicenter studies: plasma carotenoids as biomarkers of intake of fruits and vegetables.

In a multicenter study, the overall correlation between two variables can be broken down into a within- and a between-group correlation reflecting associations at the individual and aggregate levels, respectively. A random-effects model is used to estimate variance components of nutrition-related variables and the within- and between-group correlation coefficients. Using data from the European Prospective Investigation into Cancer and Nutrition (EPIC), the authors analyzed the association between levels of three plasma carotenoids (alpha-carotene, beta-cryptoxanthin, and lycopene) and dietary intake of three items (total fruits, carrots, and tomatoes), assessed through dietary questionnaire and single 24-hour dietary recall measurements, in a cross-sectional study involving 3,089 subjects from nine European countries. Intraclass correlation coefficients were 0.178 for alpha-carotene, 0.216 for beta-cryptoxanthin, and 0.299 for lycopene. The between-group correlation coefficients were higher than the within-group coefficients for all three carotenoids. For beta-cryptoxanthin and fruit intake, the between-group versus the within-group correlations were 0.78 and 0.26 for the dietary questionnaire and 0.85 and 0.19 for the 24-hour dietary recall. Results indicate that variability of exposure is driven mainly by the individual compared with the aggregate variation and that biomarker levels perform fairly accurately in discriminating population-level consumption of fruits and vegetables.

Adult↗