Neighborhood Deprivation is associated with lower levels of serum carotenoids among adults participating in the Third National Health and Nutrition Examination Survey

OBJECTIVE: This study tested the hypothesis that neighborhood deprivation will be associated with lower levels of serum carotenoids in comparison with wealthy residential areas. DESIGN: Cross-sectional, nationally representative survey data were used to assess the relationship between neighborhood level socioeconomic status and serum carotenoids. SUBJECTS: Seventeen thousand two participants aged 17 years and older from the Third National Health and Nutrition Examination Survey were linked with 1990 census data. MAIN OUTCOME MEASURES: Serum levels of lycopene, beta-carotene, alpha-carotene, lutein/zeaxanthin, and beta-cryptoxanthin. STATISTICAL ANALYSIS: Multivariate linear regression was used to model the association of serum carotenoids and neighborhood deprivation, which is a summary index of 11 indicators for tract level socioeconomic status. Adjustments are made for individual level age, sex, years of education, household income, employment, race/ethnicity, body mass index, serum cotinine, alcohol use, physical activity, and serum cholesterol. RESULTS: Multivariate analysis revealed a negative and statistically significant association between high levels of neighborhood deprivation and beta-carotene (beta=-2.98 microg/dL [-0.06 micromol/L], P=0.00), alpha-carotene (beta=-1.28 microg/dL [-0.02 micromol/L], P=<0.0001), lutein/zeaxanthin (-1.69 microg/dL [-0.03 micromol/L], P=0.00, beta-cryptoxanthin (beta=-1.34 microg/dL [-0.02 micromol/L], P<0.0001), and total carotenoids (beta=-8.20 microg/dL, P=<0.0001). Lycopene was not related to neighborhood deprivation. Adjusted mean levels of carotenoids for high deprivation neighborhoods were lower than neighborhoods with low deprivation: beta-carotene=8.72 microg/dL [0.16 micromol/L] vs 20.64 microg/dL [0.38 micromol/L], alpha-carotene=0.44 microg/dL [0.008 micromol/L] vs 5.56 microg/dL [0.10 micromol/L], lutein/zeaxanthin=13.79 microg/dL [0.24 micromol/L] vs 20.55 microg/dL [0.36 micromol/L], beta-cryptoxanthin=4.57 microg/dL [0.08 micromol/L] vs 9.93 microg/dL [0.18 micromol/L], lycopene=22.07 microg/dL [0.41 micromol/L] vs 25.63 microg/dL [0.48 micromol/L], and total=49.56 microg/dL vs 82.36 microg/dL. CONCLUSIONS: Neighborhood deprivation was associated with lower serum levels of carotenoids. There was a substantial disparity between low deprivation and high deprivation residential areas with respect to fruit and vegetable intake.     

Carotenoid status among preschool children with vitamin A deficiency in the Republic of the Marshall Islands

Although carotenoids are known to be important dietary sources of vitamin A, there have been few epidemiological studies that have characterized the serum concentrations of major dietary carotenoids among preschool children with vitamin A deficiency. We conducted a population-based, cross-sectional study of serum pro-vitamin A carotenoids (alpha -carotene, beta-carotene, beta-cryptoxanthin), non-provitamin A carotenoids (lutein/zeaxanthin, and lycopene), and retinol among 278 children, aged 1-5 y, in the Republic of the Marshall Islands. Vitamin A deficiency was defined as serum retinol <0.70 micromol/L. Geometric mean serum concentrations of carotenoids among children with and without vitamin A deficiency were 0.003 vs 0.006 micromol/L for alpha-carotene (P = 0.0017), 0.011 vs 0.023 micromol/L for beta-carotene (P <0.0001), 0.023 vs 0.034 micromol/L for beta-cryptoxanthin (P = 0.0075), 0.007 vs 0.012 micromol/L for lycopene (P = 0.037), 0.044 vs 0.052 micromol/L for lutein/zeaxanthin (P = 0.2), and 0.045 vs 0.074 micromol/L for total provitamin A carotenoids (P <0.0001) respectively. In a multivariate analysis adjusting for sex, age (Odds Ratio [O.R.] 1.44, 95% confidence interval [C.I.] 1.16-1.78), and serum provitamin A carotenoids (O.R. 0.49, 95% C.I. 0.34-0.71) were associated with vitamin A deficiency, but serum non-provitamin A carotenoids were not associated with vitamin A deficiency (O.R. 0.93, 95% C.I. 0.67-1.28). Preschool children with vitamin A deficiency in the Republic of the Marshall Islands have extremely low serum concentrations of provitamin A carotenoids and interventions are needed to improve the dietary intake of provitamin A carotenoids among Marshallese children.     

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 beta-cryptoxanthin were inversely associated with prostate cancer risk. Subjects in the highest quartile of plasma lycopene (513.7 microg/l) had a 55% lower risk of prostate cancer than those in the lowest quartile (140.5 microg/l; P trend = 0.042). No apparent association was observed for plasma alpha-carotene and beta-carotene. Further adjustment for the other 4 carotenoids did not materially alter the risk estimates for plasma lycopene, lutein/zeaxanthin, and beta-cryptoxanthin but appeared to result in an elevated risk with high levels of plasma alpha-carotene and beta-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 beta-cryptoxanthin are associated with a low risk of prostate cancer.     

Carotenoid intakes, assessed by dietary questionnaire, are associated with plasma carotenoid concentrations in an elderly population

High intakes of fruits and vegetables and of carotenoids are associated with a lower risk for a variety of chronic diseases. It is therefore important to test the validity of dietary questionnaires that assess these intakes. We compared intakes of five carotenoids, as calculated from responses to the Willett 126-item food-frequency questionnaire, with corresponding biochemical measures. Subjects included 346 women and 201 men, aged 67-93 y, in the Framingham Heart Study. Unadjusted correlations were higher among women than men as follows: alpha-carotene 0.33 and 0.18, beta-carotene, 0.36 and 0.25; beta-cryptoxanthin, 0.44 and 0.32; lycopene, 0.35 and 0.21; and lutein + zeaxanthin, 0.27 and 0.10, respectively. Adjustment for age, energy intake, body mass index (BMI, kg/m2), plasma cholesterol concentrations and smoking reduced the gender differences, respectively, to the following: alpha-carotene 0.30 and 0.28; beta-carotene, 0.34 and 0.31; beta-cryptoxanthin, 0.45 and 0.36; lycopene, 0.36 and 0.31; and lutein + zeaxanthin, 0.24 and 0.14. Plots of adjusted mean plasma carotenoid concentration by quintile of respective carotenoid intake show apparent greater responsiveness among women, compared with men, to dietary intake of alpha- and beta-carotene and beta-cryptoxanthin, but similar blood-diet relationships for lycopene and lutein + zeaxanthin. Reported daily intake of fruits and vegetables correlated most strongly with plasma beta-cryptoxanthin and beta-carotene among women and with plasma alpha- and beta-carotene among men. With the exception of lutein + zeaxanthin, this dietary questionnaire does provide reasonable rankings of carotenoid status among elderly subjects, with the strongest correlations for beta-cryptoxanthin. Appropriate adjustment of confounders is necessary to clarify these associations among men.     

Serum carotenoid concentrations in US children and adolescents

BACKGROUND: Carotenoids, a class of phytochemicals, may affect the risk of several chronic conditions. OBJECTIVE: Our objective was to describe the distributions and correlates of serum carotenoid concentrations in US children and adolescents. DESIGN: Using data from the third National Health and Nutrition Examination Survey (1988-1994), a cross-sectional study, we examined the distributions of serum concentrations of alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein and zeaxanthin, and lycopene among 4231 persons aged 6-16 y. RESULTS: After adjustment for age, sex, race or ethnicity, poverty-income ratio, body mass index status, HDL- and non-HDL-cholesterol concentrations, C-reactive protein concentration, and cotinine concentration, only HDL-cholesterol (P < 0.001) and non-HDL-cholesterol (P < 0.001) concentrations were directly related to all carotenoid concentrations. Age (P < 0.001) and body mass index status (P < 0.001) were inversely related to all carotenoid concentrations except those of lycopene. Young males had slightly higher carotenoid concentrations than did young females, but the differences were significant only for lycopene concentrations (P = 0.029). African American children and adolescents had significantly higher beta-cryptoxanthin (P < 0.001), lutein and zeaxanthin (P < 0.001), and lycopene (P = 0.006) concentrations but lower alpha-carotene (P < 0.001) concentrations than did white children and adolescents. Mexican American children and adolescents had higher alpha-carotene (P < 0.001), beta-cryptoxanthin (P < 0.001), and lutein and zeaxanthin (P < 0.001) concentrations but lower lycopene (P = 0.001) concentrations than did white children and adolescents. C-reactive protein concentrations were inversely related to beta-carotene (P < 0.001), lutein and zeaxanthin (P < 0.001), and lycopene (P = 0.023) concentrations. Cotinine concentrations were inversely related to alpha-carotene (P = 0.002), beta-carotene (P < 0.001), and beta-cryptoxanthin (P < 0.001) concentrations. CONCLUSION: These data show significant variations in serum carotenoid concentrations among US children and adolescents and may be valuable as reference ranges for this population.     

Hispanic and non-Hispanic white elders from Massachusetts have different patterns of carotenoid intake and plasma concentrations

Carotenoids have been linked with protective roles against diseases associated with aging, including cancer, cardiovascular disease, cataracts, and age-related macular degeneration. With data from a semiquantitative, validated FFQ, we examined carotenoid intake of 340 Puerto Ricans, 98 Dominicans, and 146 non-Hispanic whites (>60 y old) in Massachusetts. Compared with non-Hispanic white men, Hispanic men reported a higher intake of lycopene and lower intakes of alpha-carotene, lutein + zeaxanthin, beta-carotene (from diet only), and total beta-carotene (diet and supplements) (P < 0.001). Hispanic women reported higher intakes of beta-cryptoxanthin and lycopene but lower intakes of lutein + zeaxanthin (P < 0.001) than non-Hispanic white women. The frequency of consumption of fruit and vegetables was higher among Hispanic women, relative to non-Hispanic white women (P < 0.05). Plasma concentrations of alpha-carotene and lycopene were higher in Hispanic than in non-Hispanic white men and women. For both ethnic groups, higher intakes of carotenoids were associated with higher plasma concentrations of the respective carotenoids, except for lycopene (Hispanics) and lutein + zeaxanthin (non-Hispanic whites). Food sources contributing most to total intakes differed among the groups. The major sources of alpha- and beta-carotene were carrots for non-Hispanic whites and winter squash for Hispanics. The major source of lycopene was cooked tomato products for Hispanics, and pasta dishes for non-Hispanic whites. Traditional foods such as beans and plantains were also important contributors of carotenoids for Hispanics. Because of the potential importance of carotenoids as protective factors against chronic diseases, more attention to food-related practices associated with carotenoid intake in differing population groups is warranted.     

Acculturation in the United States is associated with lower serum carotenoid levels: Third National Health and Nutrition Examination Survey

This study examined the association of acculturation in the United States and serum carotenoid levels. The design was a cross-sectional, nationally representative survey of 16,539 participants, 17 years of age and older, from the Third National Health and Nutrition Examination Survey (NHANES III). The main outcome measures were serum levels of alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, lycopene, and total carotenoids. Multivariate linear regression was used to model the association of serum carotenoids and country of birth, language of interview, and years in the United States. Adjustments were made for age, sex, years of education, race/ethnicity, body mass index, alcohol use, physical activity, serum cotinine, serum cholesterol, and vitamin/mineral usage. Individuals born in the United States who speak English had the lowest levels of carotenoids, and individuals born in Mexico had the highest levels of carotenoids, with the exception of lycopene. Years of residence in the United States was associated with lower alpha-carotene (4.18 vs 1.51), beta-carotene (20.21 vs 14.87), beta-cryptoxanthin (12.51 vs 8.95), lutein/zeaxanthin (25.15 vs 18.03), and total carotenoids (88.79 vs 75.44). Years residence in the United States was positively associated with higher lycopene levels (26.69 vs 32.03). Acculturation in the United States was associated with lower fruit and vegetable intake, as measured by serum carotenoid levels.     

Longitudinal associations between body mass index and serum carotenoids: the CARDIA study

Cross-sectional studies report an inverse association between BMI and serum carotenoid concentration. The present study examined the prospective association between BMI and the serum concentration of five carotenoids in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Serum carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, zeaxanthin/lutein, lycopene), BMI, dietary intake, physical activity and dietary supplement use were measured at years 0 and 7 in 3071 black and white male and female participants, who were either persistent smokers or non-smokers. Among non-smokers, year 0 BMI predicted year 7 serum carotenoid levels: obese subjects (BMI > or =30 kg/m2) had an average concentration of the sum of four carotenoids (alpha-carotene +beta-carotene + zeaxanthin/lutein+beta-cryptoxanthin) that was 22 % lower than the concentration among subjects with a BMI of less than 22 kg/m2. In contrast, the sum of carotenoids among smokers was only 6 % lower. Relationships between BMI and serum lycopene were weak. The change from year 0 to year 7 in serum carotenoids, except for lycopene, was inversely associated with the change in BMI among non-smokers but not among smokers. Parallel findings were observed for BMI and serum gamma-glutamyl transferase level. In summary, the observation that BMI predicted the evolution of serum carotenoids during a 7-year follow-up among young non-smoking adults is consistent with the hypothesis that carotenoids are decreased in protecting against oxidative stress generated by adipose tissue, while smokers maintain a minimal level of serum carotenoids independent of adiposity. The results for lycopene were, however, discordant from those of the other carotenoids.     

Circulating levels of retinol, tocopherol and carotenoid in Nepali pregnant and postpartum women following long-term beta-carotene and vitamin A supplementation

OBJECTIVE: To characterize circulating carotenoid and tocopherol levels in Nepali women during pregnancy and post-partum and to determine the effects of beta-carotene and vitamin A supplementation on their concentration in serum. DESIGN: Randomized community supplementation trial. SETTING: The study was carried out from 1994 to 1997 in the Southern, rural plains District of Sarlahi, Nepal. SUBJECTS: A total of 1431 married women had an ascertained pregnancy, of whom 1186 (83%) provided an analyzable serum sample during pregnancy; 1098 (77%) provided an analyzable 3-4 months post-partum serum sample. INTERVENTIONS: Women received a weekly dose of vitamin A (7000 microg RE), beta-carotene (42 mg) or placebo before, during and after pregnancy. Serum was analyzed for retinol, alpha-tocopherol, gamma-tocopherol, beta-carotene, alpha-carotene, lycopene, lutein + zeaxanthin, and beta-cryptoxanthin concentrations during mid-pregnancy and at approximately 3 months post-partum. RESULTS: Compared to placebo, serum retinol, beta-carotene, gamma-tocopherol, beta-cryptoxanthin and lutein + zeaxanthin concentrations were higher among beta-carotene recipients during pregnancy and, except for beta-cryptoxanthin, at postpartum. In the vitamin A group, serum retinol and beta-cryptoxanthin were higher during pregnancy, and retinol and gamma-tocopherol higher at postpartum. Lutein + zeaxanthin was the dominant carotenoid, regardless of treatment group, followed by serum beta-carotene. Serum lycopene level was lowest, and very low compared to the US population. Serum retinol was higher, and carotenoid and alpha-tocopherol lower, at postpartum than during pregnancy in all groups. CONCLUSIONS: Pregnant and lactating Nepali women have lower serum carotenoid and tocopherol levels than well-nourished populations. beta-carotene supplementation appeared to increase levels of tocopherol and other carotenoids in this population.     

Plasma carotenoid response to chronic intake of selected foods and beta-carotene supplements in men.

We determined serial changes in four major plasma carotenoid fractions (alpha-carotene, beta-carotene, lutein/zeaxanthin, and lycopene) in 30 men consuming defined daily doses of carotenoids from foods (broccoli, carrots, or tomato juice) or from purified beta-carotene in capsules (12 or 30 mg) for 6 wk while fed a controlled diet. Compared with baseline, beta-carotene increased in the 30- and 12-mg-capsule and carrot groups whereas alpha-carotene increased in the carrot group and lutein increased in the broccoli group. Lower lutein concentrations in recipients of beta-carotene capsules suggested an interaction between these two carotenoids. Lycopene declined in all groups except the tomato-juice group. Total carotenoid concentration changes only reflected the large increases in beta-carotene concentrations and not the smaller changes observed in other individual carotenoids. Overall, purified beta-carotene produced a greater plasma response than did similar quantities of carotenoids from foods sources. However, some foods increased plasma concentrations of certain carotenoids.     

Hypo- and hyperresponse to egg cholesterol predicts plasma lutein and beta-carotene concentrations in men and women

The purpose of this study was to determine whether the plasma response to dietary cholesterol from eggs is associated with the plasma carotenoid response and whether gender influences the carotenoid response. Using a crossover design, 40 subjects classified as either hyper- (10 men and 10 women) or hyporesponders (10 men and 10 women) to dietary cholesterol consumed an egg (EGG, 640 mg/d additional dietary cholesterol and 600 microg lutein + zeaxanthin) or placebo (SUB, 0 mg/d cholesterol, 0 microg lutein + zeaxanthin and 568 microg beta-carotene) diet for 30 d, followed by a 3-wk washout period and the alternate diet. Plasma concentrations of lutein and beta-carotene after each dietary period were then examined to determine whether the response to carotenoid intake was similar to that seen for dietary cholesterol. After the EGG period, the increase in plasma lutein in female hyperresponders (mean increase +/- SD; 0.32 +/- 0.19 micromol/L) and male hyperresponders (0.26 +/- 0.11 micromol/L) was significantly greater than that of their hyporesponsive counterparts (0.16 +/- 0.18 micromol/L for women and 0.14 +/- 0.11 micromol/L men). Gender was not a significant factor influencing lutein response. Both men and women classified as hyperresponders significantly increased plasma beta-carotene after the SUB period, whereas their hyporesponsive counterparts were not affected. The increase in plasma beta-carotene in female hyperresponders (0.29 +/- 0.48 micromol/L) was significantly greater than that in male hyperresponders (0.07 +/- 0.07 micromol/L). We conclude that plasma responses to cholesterol and carotenoids are related and that gender influences the beta-carotene response to a greater degree than the lutein response.     

Retinol, carotenoids, and tocopherols in the milk of lactating adolescents and relationships with plasma concentrations

OBJECTIVE: We determined the concentrations of retinol, carotenoids, and tocopherols in breast milk of adolescents and evaluated their associations with plasma levels and with maternal characteristics (period of lactation, body mass index, age of menarche, and years postmenarche). METHODS: This was a single cross-sectional survey of retinol, carotenoid, and tocopherol composition of milk and plasma of lactating adolescent mothers (n = 72; 30-120 d postpartum) attending public daycare clinics in Rio de Janeiro, Brazil. Milk and plasma components were analyzed by high-performance liquid chromatography. RESULTS: Nutrient concentrations (micromoles per liter, mean +/- SE) in plasma and milk were, respectively, retinol 2.1 +/- 0.5 and 0.62 +/- 0.44, beta-carotene 0.18 +/- 0.19 and 0.016 +/- 0.017, alpha-carotene 0.05 +/- 0.04 and 0.0035 +/- 0.002, lutein plus zeaxanthin 0.15 +/- 0.11 and 0.025 +/- 0.024, lycopene 0.1 +/- 0.11 and 0.016 +/- 0.025, alpha-tocopherol 10.8 +/- 5.3 and 2.7 +/- 1.8, gamma-tocopherol 2.6 +/- 2.3 and 0.37 +/- 0.15. The milk/plasma molar ratios of retinol and tocopherols were two times higher than those of carotenoids. Significant correlations (P < 0.001) between milk and plasma nutrient levels were observed for beta-carotene (r = 0.41), alpha-carotene (r = 0.60), and lutein plus zeaxanthin (r = 0.57), but not for lycopene, retinol, and tocopherols. Nutrient concentrations in plasma and in milk were not associated with the maternal characteristics investigated. CONCLUSION: Concentrations of the nutrients studied, especially retinol and alpha-tocopherol, in mature milk of lactating adolescents were, in general, lower than in milk of adult lactating women. Milk concentrations were associated with plasma concentrations only for beta-carotene, alpha-carotene, and lutein plus zeaxanthin.     

Serum carotenoid depletion follows first-order kinetics in healthy adult women fed naturally low carotenoid diets

Dietary intakes of carotenoids are highly variable in human populations as are serum carotenoid concentrations. However, there are few controlled data relating carotenoid intake to concentration. Most of the data that are available are from measurements of the absorption and decay of large pharmacologic doses of carotenoids, and are therefore of unknown physiologic relevance. Our objective was to determine the half-life (t(1/2)) of the most abundant carotenoids in blood serum from healthy adult women living under controlled conditions. As part of two carotenoid isotopic studies, we measured serum concentrations of beta-carotene, alpha-carotene, lutein, zeaxanthin, beta-cryptoxanthin and lycopene in 19 healthy young adult women that were fed controlled low carotenoid diets for approximately 10 wk. All other nutrients (vitamins A, E and C) were provided at 100-150% of the 1989 U.S. recommended dietary allowance levels. Exercise and activities were controlled throughout the studies to simulate usual activity patterns. Carotenoid concentrations were measured by reversed-phase HPLC. Serum carotenoid concentration decreases during depletion followed first-order kinetics. The half-lives determined in decreasing order were as follows: lutein (76 d) > alpha-carotene (45 d) = beta-cryptoxanthin (39 d) = zeaxanthin (38 d) = beta-carotene (37 d) > lycopene (26 d). Half-lives were unrelated to physical or demographic characteristics such as body mass, body fat, racial background or age in these relatively homogeneous groups. Carotenoids decreased by similar first-order mechanisms, although the rates differed for individual carotenoids.     

Plasma carotenoid levels in human subjects fed a low carotenoid diet.

The purpose of this study was to investigate the effect of a low carotenoid diet on plasma carotenoid levels in humans. Twelve healthy male subjects were fed a low carotenoid diet under controlled conditions for 13 wk in a live-in metabolic unit, as part of a study of vitamin C requirement. Plasma carotenoids (zeaxanthin/lutein, cryptoxanthin, lycopene, alpha-carotene, beta-carotene) were measured with HPLC on study days 2-3, 14-15, 35-36 and 63-64. The rate of decline was rapid between d 2-3 and d 14-15, when the concentration of each carotenoid decreased significantly (P less than 0.05). Although accurate figures for half-life are not possible without more frequent sampling points, mean plasma depletion half-life seemed to be less than 12 d for beta-carotene, alpha-carotene and cryptoxanthin, between 12 and 33 d for lycopene and between 33 and 61 d for zeaxanthin/lutein. Because the decline was not linear over the study period, these data suggest the possibility of at least two body pools of these compounds, with one pool having a more rapid turnover rate. Because there is a significant decline in plasma carotenoid levels within the first 2 wk of a low carotenoid diet, determination of levels of these compounds may be useful only in the assessment of short-term intake.     

Carotenoids are decreased in biopsies from colorectal adenomas

A lower intake of carotenoids is associated with an increased risk of colorectal cancer. In order to take advantage of the chemopreventive properties of carotenoids, it is necessary to determine carotenoid concentration at the target tissue. As early stages in the adenoma-carcinoma sequence of colorectal cancer might be susceptible to chemoprevention, we sought to determine carotenoid concentrations in biopsies from colorectal adenomas. METHODS: Biopsies from colorectal adenomas and non-involved mucosa were taken from seven patients. For controls, biopsies were obtained from the ascending and descending colon of patients without polyps (n = 5). Concentration of carotenoids (alpha-, beta-carotene, lutein, lycopene, zeaxanthin, beta-cryptoxanthin) were determined by optimizing gradient HPLC-analysis. Results are expressed as pmol/microg DNA. RESULTS: Except for alpha-carotene, all carotenoids could reliably be detected in all specimens. In control patients carotenoid concentrations were highest in the ascending colon, being followed by the descending colon and non-involved mucosa from polyp-carriers. In colorectal adenomas all carotenoids were significantly reduced as compared to-non-involved mucosa (beta-carotene: 0.37 vs 0.19, P<0.03; lycopene: 0.34 vs 0.21, P<0.06, beta-cryptoxanthin: 0.14 vs 0.09, P<0.03, zeaxanthin: 0.18 vs 0.09, P<0.02; lutein: 0.18 vs 0.13,P <0.02). CONCLUSION: All carotenoids investigated are reduced in colorectal adenomas, suggesting that mucosal carotenoids could serve as biomarkers for predisposition to colorectal cancer. Moreover, anti-tumor activity exerted by carotenoids is limited due to mucosal depletion. We speculate that supplementation of a larger array of carotenoids might be beneficial for patients with colorectal adenoma.     

Nonsupplemented children of Latino immigrants have low vitamin E intakes and plasma concentrations and normal vitamin C, selenium, and carotenoid intakes and plasma concentrations

OBJECTIVE: This study sought to determine and evaluate the intakes and plasma concentrations of vitamin E (alpha-tocopherol), gamma-tocopherol, vitamin C, selenium, and carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, and lycopene) of nonsupplemented boys and girls, 4 to 8 years old, of Latino immigrants living in rural Nebraska. DESIGN: Dietary intakes of the Latino children were estimated. Their plasma samples (fasting) were analyzed for vitamin E, vitamin C, selenium, and carotenoid concentrations. Data were evaluated by sex. SUBJECTS: The subjects were a convenience sample of 4- to 8-year-old (n=29), apparently healthy, nonsupplemented children of Latino immigrants living in rural Nebraska. STATISTICAL ANALYSIS: Sex differences in parameter values were determined using general linear models; Pearson r was used for determining correlations. RESULTS: No significant differences in parameter values were observed by sex, with the exception of plasma lutein/zeaxanthin concentration. The majority (69%) had plasma vitamin E (alpha-tocopherol) concentrations<0.516 mg/dL (12 micromol/L), which is indicative of vitamin E inadequacy, and over half (59%) reported consuming less than the Estimated Average Requirement for vitamin E. All subjects had plasma vitamin C and selenium concentrations indicative of adequacy (>0.41 mg/dL or >23 micromol/L, and >6.32 microg/dL or >0.8 micromol/L, respectively), and consumed at least the Recommended Dietary Allowances for these nutrients. The plasma carotenoid concentrations of the children may be useful as norms. CONCLUSIONS: These children of Latino immigrants who did not take supplements had low plasma vitamin E (alpha-tocopherol) concentrations but normal plasma vitamin C and selenium concentrations. IMPLICATIONS: Dietetics professionals and others involved in health care need to work with Latino immigrant parents so that their children consume adequate amounts of vitamin E.     

Airway and circulating levels of carotenoids in asthma and healthy controls

BACKGROUND: Elevated oxidative stress and impaired antioxidant defences are increasingly recognised features of asthma. Carotenoids are potent dietary antioxidants that may protect against asthma by reducing oxidative damage. OBJECTIVES: This study aimed firstly, to characterise circulating and airway levels of carotenoids in asthma compared to healthy controls, in relation to dietary intake. Secondly, the study aimed to test whether airway lycopene defences can be improved using oral supplements. METHODS: Induced sputum and peripheral blood samples were collected from subjects with asthma (n = 15) and healthy controls (n = 16). Dietary carotenoid intakes were estimated using the 24-hour recall method and analysed using a modified version of the Foodworks 210 Nutrient Calculation Software. Another group of healthy controls (n = 9) were supplemented with 20 mg/day lycopene for 4 weeks. Carotenoids (beta-carotene, lycopene, alpha-carotene, beta-cryptoxanthin, lutein/zeaxanthin) were measured by HPLC. RESULTS: Despite similar dietary intake, whole blood levels of total carotenoids, lycopene, lutein, beta-cryptoxanthin, alpha-carotene and beta-carotene were significantly lower in asthma than controls. However, there were no differences in plasma or sputum carotenoid levels. Induced sputum carotenoid levels were significantly lower than plasma and whole blood levels, but correlated strongly with plasma levels (r = 0.798, p < 0.001). Although there were no overall increases in either plasma or sputum lycopene levels following supplementation, changes in airway lycopene levels correlated with changes in plasma levels (r = 0.908, p < 0.002). CONCLUSIONS: Whole blood, but not plasma or sputum, carotenoid levels are deficient in asthma. Plasma carotenoid levels reflect airway carotenoid levels and when plasma levels are improved using oral supplements this is reflected in the airways.     

Relation between dietary intake, serum concentrations, and retinal concentrations of lutein and zeaxanthin in adults in a Midwest population.

BACKGROUND: Information on concentrations of retinal carotenoids (macular pigment, or MP) is of particular interest because MP protects against age-related macular degeneration, the leading cause of irreversible blindness in the United States. OBJECTIVE: This study was designed to evaluate the relation between dietary intake, blood concentrations, and retinal concentrations of carotenoids in a large group of volunteers. DESIGN: Two hundred eighty volunteers in the Indianapolis area completed health and diet questionnaires, donated a blood sample, and participated in MP density assessment to determine retinal carotenoid status. Dietary intake was assessed by food-frequency questionnaire. Serum concentrations of lutein, zeaxanthin, and beta-carotene were measured by HPLC. MP optical density (MPOD) was determined psychophysically with a 460-nm, 1 degrees test stimulus. RESULTS: Average MPOD was 0.21 +/- 0.13. Average intakes of lutein + zeaxanthin and beta-carotene were 1101 +/- 838 and 2935 +/- 2698 microg/d, respectively. Although several key dietary intake variables (eg, lutein + zeaxanthin and beta-carotene) differed by sex, no significant sex differences were found in either serum concentrations of lutein and zeaxanthin or MPOD. Serum beta-carotene concentrations were significantly higher in women than in men. Serum lutein + zeaxanthin and dietary intake of lutein + zeaxanthin were significantly correlated and significantly related to variations in MPOD (r = 0.21, P < 0.001, and r = 0.25, P < 0.001, respectively). CONCLUSIONS: Retinal carotenoids can be measured in epidemiologic studies. In this study, MPOD was associated with lutein + zeaxanthin in the diet and the serum. Retinal concentrations, however, were influenced by other factors as well. To understand the effect of dietary lutein + zeaxanthin intake on the retina and risk of age-related eye disease, future studies should include measures of macular concentrations of these pigments.     

Plasma carotenoids, retinol, and tocopherols and risk of breast cancer

The roles of carotenoids, retinol, and tocopherols in breast cancer etiology have been inconclusive. The authors prospectively assessed the relations between plasma alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, lutein/zeaxanthin, retinol, alpha-tocopherol, and gamma-tocopherol and breast cancer risk by conducting a nested case-control study using plasma collected from women enrolled in the Nurses' Health Study. A total of 969 cases of breast cancer diagnosed after blood draw and prior to June 1, 1998, were individually matched to controls. The multivariate risk of breast cancer was 25-35% less for women with the highest quintile compared with that for women with the lowest quintile of alpha-carotene (odds ratio (OR) = 0.64, 95% confidence interval (CI): 0.47, 0.88; p(trend) = 0.01), beta-carotene (OR = 0.73, 95% CI: 0.53, 1.02; p(trend) = 0.01), lutein/zeaxanthin (OR = 0.74, 95% CI: 0.55, 1.01; p(trend) = 0.04), and total carotenoids (OR = 0.76, 95% CI: 0.55, 1.05; p(trend) = 0.05). The inverse association observed with alpha-carotene and breast cancer was greater for invasive cancers with nodal metastasis. The authors conclude that some carotenoids are inversely associated with breast cancer. Although the association was strongest for alpha-carotene, the high degree of collinearity among plasma carotenoids limits our ability to conclude that this association is specific to any individual carotenoid.     

Bioavailability of lutein from vegetables is 5 times higher than that of beta-carotene.

BACKGROUND: To gain more insight into the relation between vegetable consumption and the risk of chronic diseases, it is important to determine the bioavailability of carotenoids from vegetables and the effect of vegetable consumption on selected biomarkers of chronic diseases. OBJECTIVE: To assess the bioavailability of beta-carotene and lutein from vegetables and the effect of increased vegetable consumption on the ex vivo oxidizability of LDL. DESIGN: Over 4 wk, 22 healthy adult subjects consumed a high-vegetable diet (490 g/d), 22 consumed a low-vegetable diet (130 g/d), and 10 consumed a low-vegetable diet supplemented with pure beta-carotene (6 mg/d) and lutein (9 mg/d). RESULTS: Plasma concentrations of vitamin C and carotenoids (ie, alpha-carotene, beta-carotene, lutein, zeaxanthin, and beta-cryptoxanthin) were significantly higher after the high-vegetable diet than after the low-vegetable diet. In addition to an increase in plasma beta-carotene and lutein, the pure carotenoid-supplemented diet induced a significant decrease in plasma lycopene concentration of -0.11 micromol/L (95% CI: -0.21, -0.0061). The responses of plasma beta-carotene and lutein to the high-vegetable diet were 14% and 67%, respectively, of those to the pure carotenoid- supplemented diet. Conversion of beta-carotene to retinol may have attenuated its plasma response compared with that of lutein. There was no significant effect on the resistance of LDL to oxidation ex vivo. CONCLUSIONS: Increased vegetable consumption enhances plasma vitamin C and carotenoid concentrations, but not resistance of LDL to oxidation. The relative bioavailability of lutein from vegetables is higher than that of beta-carotene.