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.     

Higher intake of carotenoid is associated with a lower risk of colorectal cancer in Chinese adults: a case–control study

Purpose

The associations between specific carotenoid intake and colorectal cancer risk remain inconsistent. The aim of this study was to examine the association between specific dietary carotenoid intake with colorectal cancer risk in Chinese adults.

Method

From July 2010 to October 2013, 845 eligible colorectal cancer cases and 845 frequency-matched controls (age and sex) completed in-person interviews. A validated food frequency questionnaire was used to estimate dietary intake. Multivariate logistical regression models were used to calculate the odds ratio (OR) and 95 % confidence intervals (95 % CIs) of colorectal cancer risk after adjusting for various confounders.

Results

A strong inverse association was found between β-cryptoxanthin intake and colorectal cancer risk. Compared with the lowest quartile, the highest quartile intake showed a risk reduction of 77 % (OR 0.23, 95 % CI 0.17–0.33, P _trend < 0.01) after adjustment for various confounding variables. The inverse associations were also observed for α-carotene (OR 0.50, 95 % CI 0.37–0.68, P _trend < 0.01), β-carotene (OR 0.67, 95 % CI 0.49–0.91, P _trend < 0.01), and lycopene (OR 0.51, 95 % CI 0.37–0.70, P _trend < 0.01). There was no statistically significant association between lutein/zeaxanthin intake and colorectal cancer risk. These findings were consistent across cancer site, sources of controls, and smoking status. The inverse associations between dietary α-carotene, β-cryptoxanthin, and lycopene intake and colorectal cancer risk were found in both males and females, while inverse associations between β-carotene intake and colorectal cancer risk were only observed in males.

Conclusions

Consumption of α-carotene, β-carotene, β-cryptoxanthin, and lycopene was inversely associated with colorectal cancer risk. No significant association was found between lutein/zeaxanthin intake and colorectal cancer risk.

     

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.     

Effects of formulation on the bioavailability of lutein and zeaxanthin: a randomized, double-blind, cross-over, comparative, single-dose study in healthy subjects

Purpose

Lutein and zeaxanthin are macular pigments with a protective function in the retina. These xanthophylls must be obtained from the diet or added to foods or supplements via easy-to-use, stable formulations. The technique employed to produce these formulations may affect the bioavailability of the xanthophylls.

Methods

Forty-eight healthy volunteers were randomized into this double-blind, cross-over study investigating the plasma kinetics of lutein provided as two different beadlet formulations. Subjects (n = 48) received a single dose of 20 mg of lutein as either a starch-matrix (“SMB”, FloraGLO^® Lutein 5 %) or as a cross-linked alginate-matrix beadlet (“AMB”, Lyc-O-Lutein 20 %) formulation. Plasma concentrations of lutein and zeaxanthin were measured at 0, 1, 3, 6, 9, 12, 14, 24, 26, 28, 32, 36, 48, 72, 168, and 672 h.

Results

The mean plasma AUC_(0–72h), AUC_(0–672h), and C _max for total lutein and zeaxanthin and their all-E-isomers were significantly increased (p < 0.001) from pre-dose concentrations in response to SMB and AMB. There was no difference in lutein T _max between the two test articles. However, by 14 h post-dose, total plasma lutein increased by 7 % with AMB and by 126 % with SMB. Total lutein AUC_(0–72h) and AUC_(0–672h) were 1.8-fold and 1.3-fold higher, respectively, for SMB compared to AMB. Both formulations were well tolerated by subjects in this study.

Conclusion

These findings confirm that the bioavailability of lutein and zeaxanthin critically depends on the formulation used and document a superiority of the starch-based over the alginate-based product in this study.     

Effects of curcumin on retinal oxidative stress and inflammation in diabetes

Background

Age-related macular degeneration (AMD) is a disease with multiple risk factors, many of which appear to involve oxidative stress. Macular pigment, with its antioxidant and light-screening properties, is thought to be protective against AMD. A result has been the appearance of dietary supplements containing the macular carotenoids, lutein and zeaxanthin. More recently, a supplement has been marketed containing, in addition, the third major carotenoid of the macular pigment, meso-zeaxanthin. The purpose of the study was to determine the effectiveness of such a supplement in raising macular pigment density in human subjects.

Methods

A 120 day supplementation study was conducted in which 10 subjects were given gel-caps that provided 20 mg/day of predominantly meso-zeaxanthin, with smaller amounts of lutein and zeaxanthin. A second group of 9 subjects were given gel caps containing a placebo for the same 120 day period. Prior to and during the supplementation period, blood serum samples were analyzed by high performance liquid chromatography for carotenoid content. Similarly, macular pigment optical density was measured by heterochromatic flicker photometry. Differences in response between the supplementation and placebo groups were tested for significance using a student's t-test.

Results

During supplementation with the carotenoids, blood samples revealed the presence of all three carotenoids. Macular pigment optical density, measured at 460 nm, rose at an average rate of 0.59 ± 0.79 milli-absorbance unit/day in the 10 supplemented subjects. This was significantly different from the placebo group (9 subjects) for whom the average rate was -0.17 ± 0.42 milli-absorbance units/day.

Conclusion

We have shown for the first time that meso-zeaxanthin is absorbed into the serum following ingestion. The data indicate that a supplement containing predominantly meso-zeaxanthin is generally effective at raising macular pigment density, and may turn out to be a useful addition to the defenses against AMD.     

Total and individual carotenoid profiles in Solanum phureja of cultivated potatoes: I. Concentrations and relationships as determined by spectrophotometry and HPLC

Total and individual carotenoid concentrations were determined by spectrophotometry and HPLC, in raw tubers of a sample of 23 accessions of Solanum phureja potatoes taken at random from the world germplasm collection following its stratification on tuber flesh color. Lutein, zeaxanthin, violaxanthin, antheraxanthin and β-carotene were detected in all accessions and three distinct patterns of carotenoid accumulation were evidenced by cluster analysis. Accessions in group 1 showed the highest concentrations of total carotenoids (1258–1840 μg 100 g⁻¹ FW) comprised largely of zeaxanthin (658–1290 μg 100 g⁻¹ FW) with very low or no presence of β-carotene (below 5.4 μg 100 g⁻¹ FW). Accessions in group 2 presented moderate total carotenoid concentrations with violaxanthin, antheraxanthin, lutein and zeaxanthin as the major carotenoids. Accessions in group 3 showed low concentrations of total carotenoids (97–262 μg 100 g⁻¹ FW) and very low or no zeaxanthin, with lutein and violaxanthin as the predominant carotenoids and relatively high concentrations of β-carotene (up to 27 μg 100 g⁻¹ FW). Five accessions with significant concentrations of zeaxanthin were identified with the accession 703566 showing the highest concentration (1290 μg 100 g⁻¹ FW). This value is to our knowledge higher than any value previously reported for potatoes, including those achieved through genetic modification. For the 23 S. phureja accessions, total carotenoid concentration was positively and significantly correlated with antheraxanthin and zeaxanthin concentrations, and negatively and significantly correlated with β-carotene concentration.     

Increased consumption of dietary cholesterol,lutein, and zeaxanthin as egg yolks does not decrease serum concentrations and lipoprotein distribution of other carotenoids,retinol, and tocopherols

We have previously reported that consumption of lutein and zeaxanthin as 2 and 4 egg yolks per day for 5 weeks significantly increased serum lutein and zeaxanthin concentrations in older adults taking cholesterol-lowering statins. We hypothesized that increased consumption of eggs, lutein, and zeaxanthin may correlate with decreased absorption of other carotenoids and increased absorption of vitamins A and E, thus affecting their serum concentrations and lipoprotein distribution. Fifty-two subjects aged at least 60 years consumed 2 egg yolks per day followed by 4 egg yolks per day for 5 weeks each with a 4-week egg-free period at baseline and between the 2 interventions. Mean serum β-cryptoxanthin, lycopene, α-carotene, β-carotene, α-tocopherol, and retinol concentrations did not change during the 2 and 4 egg yolk phases. Mean serum α-cryptoxanthin and γ-tocopherol concentrations did not change after the 2 egg yolk phase, but increased by 47% (P < .001) and 19% (P < .05), respectively, after the 4 egg yolk phase. The percentage distribution of carotenoids and tocopherols between the high-density lipoprotein (HDL) and non-HDL fractions was not significantly different during the egg yolk phases compared with baseline despite the significant increases in lutein and zeaxanthin carried on HDL and non-HDL fractions. In conclusion, increased dietary cholesterol, lutein, and zeaxanthin consumed as egg yolks did not decrease the absorption of other carotenoids, and increased γ-tocopherol but not retinol as evidenced by their serum and lipoprotein concentrations. Two and 4 egg yolk consumption increases serum and retinal lutein and zeaxanthin without altering the serum status of the other carotenoids, tocopherol, and retinol.     

Supplementation of highly concentrated β-cryptoxanthin in a satsuma mandarin beverage improves adipocytokine profiles in obese Japanese women

Background

Serum ??-cryptoxanthin levels are lower in overweight subjects than in normal subjects. Abnormalities of adipocytokine profiles in obesity subjects have been reported. There are several reports that serum ??-cryptoxanthin levels in them were relatively lower than normal subjects.

Objective

We hypothesize that supplementation of highly concentrated ??-cryptoxanthin improves serum adipocytokine profiles in obese subjects. This study tested the association between ??-cryptoxanthin intake and serum adipocytokine levels.

Methods

An intervention study consisted of a 3-week long before-and-after controlled trial, where ??-cryptoxanthin (4.7?mg/day) was given to 17 moderately obese postmenopausal women.

Results

The results indicated no significant changes in body weight or body mass index (BMI). Serum ??-cryptoxanthin levels increased significantly by 4-fold. Serum high molecular weight (HMW)-adiponectin levels increased significantly, while serum plasminogen activator inhibitor (PAI)-1 levels decreased.

Conclusions

We concluded that increasing the intake of ??-cryptoxanthin to approximately 4?mg per day for 3?weeks may have beneficial effects on the serum adipocytokine status and consequently alleviate progression of metabolic syndrome.     

Olive oil improves the intestinal absorption and bioavailability of lutein in lutein-deficient mice

Purpose

To investigate the influence of olive (OO), groundnut (GNO), soybean (SBO), sunflower (SFO), rice bran (RBO), corn (CO), palm (PO) oil or mixed micelle (control) on absorption kinetics and bioavailability of lutein in lutein-deficient mice. Additional aim was to correlate the activity of intestinal triacylglycerol lipase with intestinal and plasma lutein levels.

Methods

After induction of lutein deficiency, mice (n = 165) were divided into eight groups (OO, SFO, GNO, RBO, PO, CO, SBO and control; n = 20/group) and the remaining (n = 5) were used as baseline (0 h). Groups were further divided into four subgroups (n = 5/subgroup) and were intubated with lutein (200 μM) dispersed in different vegetable oils. Plasma and tissue (intestine, liver and eyes), lutein, triglycerides, intestinal triacylglycerol lipases and fatty acid profile of plasma and tissues were measured at different time intervals.

Results

The percentage area under the curve value for plasma lutein in OO and GNO was higher by 41.8 and 5.1 %, while it was lower in other groups (18.2–53.3 %), when compared to control. Similarly, the percentage area under the curve for eye lutein in OO and GNO groups was higher by 35.2 and 4.8 %, whereas in other groups it was lower (5.4–69 %) than in control. Results show that olive oil facilitates the lutein absorption more compared to other vegetable oils, which may be due to the difference in fatty acid composition and higher activity of intestinal triacylglycerol lipase.

Conclusions

Dietary olive oil rich in oleic acid improves the bioavailability and accumulation of lutein in lutein-deficient mice by modifying the intestinal triacylglycerol lipase activity.     

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。     

Association Between Serum Levels of Carotenoids and Serum Asymmetric Dimethylarginine Levels in Japanese Subjects

Background

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelium nitric oxide synthase (NOS). ADMA binds to a substrate-binding site of NOS and then inhibits nitric oxide production from vascular endothelial cells. Elevated ADMA levels are a risk factor for cardiovascular disease. Recently, it was reported that plasma ADMA levels were negatively correlated with vegetable and fruit consumption. The purpose of this study was to examine the association between serum levels of carotenoids and serum ADMA levels in Japanese subjects.

Methods

We conducted a cross-sectional study of 470 subjects (203 men and 267 women) who attended a health examination in August 2011. Serum levels of several carotenoids were separately measured by high-performance liquid chromatography. Serum ADMA levels were determined by using an enzyme-linked immunosorbent assay kit.

Results

In women, the multivariate-adjusted odds ratios (ORs) of elevated serum ADMA levels were significantly decreased in the highest tertile for β-cryptoxanthin (OR 0.47, 95% CI 0.23–0.95), α-carotene (OR 0.39, 95% CI 0.18–0.79), and β-carotene (OR 0.36, 95% CI 0.17–0.73) compared to the lowest tertile. In men, significantly decreased ORs were observed in the highest tertiles of serum zeaxanthin/lutein (OR 0.23, 95% CI 0.06–0.69) and α-carotene (OR 0.26, 95% CI 0.07–0.82), and in the middle and the highest tertiles of serum β-carotene (OR 0.27, 95% CI 0.09–0.74 and OR 0.20, 95% CI 0.03–0.88, respectively) when the tertile cutoff points of women were extrapolated to men.

Conclusions

Higher serum levels of carotenoids, such as α-carotene and β-carotene, may help to prevent elevated serum ADMA levels in Japanese subjects.Key words: asymmetric dimethylarginine, carotenoids, cross-sectional study     

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。     

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.     

Effect of increasing fruit and vegetable intake by dietary intervention on nutritional biomarkers and attitudes to dietary change: a randomised trial

Purpose

Low fruit and vegetable consumption is linked with an increased risk of death from vascular disease and cancer. The benefit of eating fruits and vegetables is attributed in part to antioxidants, vitamins and phytochemicals. Whether increasing intake impacts on markers of disease remains to be established. This study investigates whether increasing daily intake of fruits, vegetables and juices from low (approx. 3 portions), to high intakes (approx. 8 portions) impacts on nutritional and clinical biomarkers. Barriers to achieving the recommended fruit and vegetable intakes are also investigated.

Method

In a randomised clinical trial, the participants [19 men and 26 women (39–58 years)] with low reported fruit, juice and vegetable intake (<3 portions/day) were randomised to consume either their usual diet or a diet supplemented with an additional 480 g of fruit and vegetables and fruit juice (300 ml) daily for 12 weeks. Nutritional biomarkers (vitamin C, carotenoids, B vitamins), antioxidant capacity and genomic stability were measured pre-intervention, at 4-, 8- and 12 weeks throughout the intervention. Samples were also taken post-intervention after a 6-week washout period. Glucose, homocysteine, lipids, blood pressure, weight and arterial stiffness were also measured. Intake of fruit, fruit juice and vegetables was reassessed 12 months after conducting the study and a questionnaire was developed to identify barriers to healthy eating.

Results

Intake increased significantly in the intervention group compared to controls, achieving 8.4 portions/day after 12 weeks. Plasma vitamin C (35%), folate (15%) and certain carotenoids [α-carotene (50%) and β-carotene (70%) and lutein/zeaxanthin (70%)] were significantly increased (P < 0.05) in the intervention group. There were no significant changes in antioxidant capacity, DNA damage and markers of vascular health. Barriers to achieving recommended intakes of fruits and vegetables measured 12 months after the intervention period were amount, inconvenience and cost.

Conclusion

While increasing fruit, juice and vegetable consumption increases circulating level of beneficial nutrients in healthy subjects, a 12-week intervention was not associated with effects on antioxidant status or lymphocyte DNA damage.

Trial registration

This trial was registered at Controlled-Trials.com; registration ISRCTN71368072.

     

Low levels of plasma carotenoids are associated with an increased risk of atrial fibrillation

Systemic inflammation, oxidative stress, and atrial fibrosis are identified as the main mechanisms for atrial fibrillation (AF). Antioxidant micronutrients may have antiarrhythmic benefit in humans. We studied whether plasma carotenoids are related to the risk of AF in elderly subjects. The study population consisted of 1,847 Finnish subjects (620 women and 1,227 men) aged 61–82 years from the Kuopio Ischaemic Heart Disease Risk Factor study cohort. Plasma concentrations of carotenoids were measured by high-performance liquid chromatography. The multivariable-adjusted hazard ratios (HRs) and 95 % confidence intervals (CIs) of plasma carotenoids were analyzed using the Cox proportional hazard’s model. During a median follow-up of 2.8 years a total of 105 subjects developed incident AF. The HRs of AF among subjects with levels in the highest through the lowest tertile after adjustment for age, examination year, gender, systolic blood pressure, smoking, alcohol consumption, education, diabetes, use of antihypertensive medication, congestive heart failure, recurrent AF, prevalent coronary heart disease and baseline prevalence of myocardial infarction were 1.70 (95 % CI: 1.01–2.86, p = 0.047) for lutein, 1.99 (95 % CI: 1.14–3.48, p = 0.016) for zeaxanthin. Risk of AF was borderline significant for β-carotene (HR = 1.69, 95 % CI: 1.00–2.87, p = 0.050). Results remained unchanged, when season was added to the multivariable model. Lycopene, β-cryptoxanthin, α-carotene and total carotenoids were not associated with the risk of AF. Results of the present study suggest that low plasma concentrations of lutein and zeaxanthin were associated with an increased risk of AF in elderly population.     

Genetic diversity of nutritionally important carotenoids in 94 pea and 121 chickpea accessions

Biofortification of staple crops via breeding is an attractive strategy for reducing human micronutrient deficiencies. The objective of this research was to examine the concentration of carotenoids in diverse pea and chickpea accessions grown in Saskatchewan (Canada) using high performance liquid chromatography. In pea accessions mean concentration of lutein was highest (11.2 μg g⁻¹) followed by β-carotene (0.5 μg g⁻¹), zeaxanthin (0.3 μg g⁻¹), and violaxanthin (0.3 μg g⁻¹). Green cotyledon pea accessions were richer in β-carotene and total carotenoids compared to yellow cotyledon accessions. In chickpea accessions mean concentration of lutein (8.2 μg g⁻¹) was highest followed by zeaxanthin (6.2 μg g⁻¹), β-carotene (0.5 μg g⁻¹), β-cryptoxanthin (0.1 μg g⁻¹), and violaxanthin (0.1 μg g⁻¹). Desi chickpea accessions had higher carotenoid concentration than kabuli accessions. This research identified pea and chickpea accessions that can be utilized in breeding for the improvement of carotenoid concentration through biofortification.     

Industrially viable processes for synthesis of biologically active hydroxycarotenoids commonly found in fruits and vegetables

Human plasma and tissues contain in excess of 12 dietary carotenoids and several metabolites that originate from consumption of fruits and vegetables. The major hydroxycarotenoids absorbed by humans are: (3R,3′R,6′R)-lutein (1), (3R,3′R)-zeaxanthin (2), (3R,6′R)-α-cryptoxanthin (3), and (3R)-β-cryptoxanthin (4) and their E/Z-stereoisomers. In addition, several hydroxycarotenoids that result from metabolic transformation of 1 have also been identified in human plasma and ocular tissues. Epidemiological and experimental evidence to date suggest hydroxycarotenoids may protect against chronic diseases such as cancer, cardiovascular disease and age-related macular degeneration (AMD). Therefore, supplementation with these carotenoids in individuals with a low dietary intake of fruits and vegetables is essential. However, with the exception of 1 and 2, industrial production of 3 and 4 have not yet materialized. A relatively straightforward semisynthetic process has been developed that transform 1 into a mixture of 3 (12%) and 4 (80%). Hydroxycarotenoid 3 can also be directly prepared from allylic deoxygenation of 1 in a single step in an excellent yield. These two processes provide an easy access to optically active 3 and 4 that are normally prepared by numerous synthetic steps.     

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.