Plasma Beta-carotene Concentrations Research Articles

β-Carotene Supplementation Increases Antioxidant Capacity of Plasma in Older Women , ,

The antioxidant effect of dietary beta-carotene supplementation on the peroxidation potential of plasma was investigated in a randomized double-blind, placebo-controlled study. Twelve healthy women (62-80 y) supplemented their usual daily diet with 90 mg of beta-carotene (n = 6) or placebo (n = 6) capsules for 3 wk. Plasma concentrations of beta-carotene, alpha- and gamma-tocopherol, ascorbate, urate, bilirubin and in vitro production of phosphatidylcholine hydroperoxides (PC-OOH) and utilization of plasma antioxidants in the presence of 50 mmol/L 2,2'-azobis (2-aminopropane) hydrochloride (AAPH), a free radical generator, at 37 degrees C were measured before and after dietary treatment. Plasma beta-carotene increased from 0.76 +/- 0.16 to 6.45 +/- 1.16 micromol/L (P < 0.05) in supplemented but not placebo-treated subjects. The plasma concentrations of other antioxidants did not change significantly in either group. beta-Carotene supplementation did not affect basal levels of plasma PC-OOH as measured by HPLC post-column chemiluminescence but did affect AAPH-induced production of PC-OOH. Before supplementation, the induction period of plasma PC-OOH production was 2.4 +/- 0.4 h, with levels reaching 5.39 +/- 1.50 micromol/L after 6 h of incubation. After supplementation, the induction period increased significantly to 4.2 +/- 0.4 h (P < 0.01), with a lower PC-OOH production of 2.16 +/- 0.90 micromol/L after 6 h (P < 0.05). In this system, plasma ascorbate concentrations were depleted first, followed by loss of bilirubin and alpha-tocopherol and then by the sequential loss of gamma-tocopherol, urate and beta-carotene. These results indicate that beta-carotene supplementation increases the plasma antioxidant capacity of older women.

Influence of specific management practices on blood selenium, vitamin E, and beta‐carotene concentrations in horses and risk of nutritional deficiency

BackgroundSelenium or alpha‐tocopherol deficiency can cause neuromuscular disease. Beta‐carotene has limited documentation in horses.ObjectiveTo evaluate the effect of owner practices on plasma beta‐carotene concentration and risk of selenium and alpha‐tocopherol deficiencies.AnimalsThree‐hundred and forty‐nine adult (≥1 year), university and privately owned horses and mules.MethodsCross‐sectional study. Whole blood selenium, plasma alpha‐tocopherol, and plasma beta‐carotene concentrations were measured once. Estimates of daily selenium and vitamin E intake, pasture access, and exercise load were determined by owner questionnaire. Data were analyzed using t tests, Mann‐Whitney tests, parametric or nonparametric analysis of variance (ANOVA), Kruskal‐Wallis test, Spearman's correlation and contingency tables (P < .05).ResultsNearly 88% of the horses received supplemental selenium; 71.3% received ≥1 mg/d. Low blood selenium concentration (<80 ng/mL) was identified in 3.3% of horses, and 13.6% had marginal concentrations (80‐159 ng/mL). Non‐supplemented horses were much more likely to have low blood selenium (odds ratio [OR], 20.2; 95% confidence interval [CI], 9.26‐42.7; P < .001). Supplemental vitamin E was provided to 87.3% of horses; 57.7% received ≥500 IU/d. Deficient (<1.5 μg/mL) and marginal (1.5‐2.0 μg/mL) plasma (alpha‐tocopherol) occurred in 15.4% and 19.9% of horses, respectively. Pasture access (>6 h/d) and daily provision of ≥500 IU of vitamin E was associated (P < .001) with higher plasma alpha‐tocopherol concentrations. Plasma beta‐carotene concentration was higher in horses with pasture access (0.26 ± 0.43 versus 0.12 ± 0.13 μg/mL, P = .003).Conclusions and Clinical ImportanceSuboptimal blood selenium and plasma alpha‐tocopherol concentrations occurred in 16.7% and 35.5% of horses, respectively, despite most owners providing supplementation. Inadequate pasture access was associated with alpha‐tocopherol deficiency, and reliance on selenium‐containing salt blocks was associated with selenium deficiency.

Association of concentrations of beta-carotene in plasma on pregnancy per artificial insemination and pregnancy loss in lactating Holstein cows

The objective of this study was to determine the association of beta-carotene concentration in plasma at the moment of artificial insemination (AI) on pregnancy/AI in lactating Holstein cows. A total of 399 events from 364 lactating Holstein cows were enrolled in the trial (143 primiparous and 221 multiparous). All cows were assigned to a timed AI protocol based on estradiol and progesterone. Blood samples were collected at the moment of AI and at 24 and 31d post-AI (samples on 31 d post-AI were collected only from cows that were diagnosed pregnant). The BCS were recorded at the time of AI. Plasma beta-carotene was quantified from blood samples taken at the time of AI using a single step denaturation and extraction into a solvent, followed by measurement using a portable spectrophotometer. Pregnancy-associated glycoproteins (PAG) were analyzed in blood samples taken at 24 and 31 d post-AI of pregnant cows. Milk production was collected for the entire experimental period. Pregnancy diagnosis was performed by ultrasound 31 and 60 d post-AI. Data was analyzed using the MIXED and GLIMMIX procedures of SAS. Cows classified as thin (<2.75) tended to have lower concentration of beta-carotene at AI when compared with those classified as Moderate (≥3.00; 3.8 ± 0.1 vs. 4.3 ± 0.1 μg/mL; P = 0.09). Concentration of beta-carotene were greater in multiparous compared with primiparous (P < 0.01). There was no correlation between concentration of beta-carotene and milk production (r = 0.04; P = 0.10). When plasma beta-carotene was categorized in quartiles, cows in the 1st quartile had lower pregnancy/AI and higher pregnancy losses when compared with cows that were in the 2nd, 3rd and 4th quartile (pregnancy/AI = 19.2 ± 4.5, 33.7 ± 4.7, 36.9 ± 5.0 and 39.8 ± 5.4%, respectively; P = 0.05; pregnancy losses = 41.9 ± 4.8, 20.4 ± 3.7, 22.1 ± 4.1, and 15.7 ± 4.2%, respectively; P < 0.05). There was no association between concentrations of beta-carotene at AI and PAG at 24 d post-AI (P = 0.60). Cows with greater concentrations of beta-carotene at AI were more likely to have greater concentrations of PAG at 31 d post-AI (P < 0.01). In conclusion, the concentration of beta-carotene at AI was affected by BCS and parity. Cows with higher concentrations of plasma beta-carotene at AI had greater pregnancy/AI, lower pregnancy losses and greater concentrations of PAG at d 31 post-AI, suggesting it may be associated with placental function in lactating dairy cows.

Red palm olein supplementation on cytokines, endothelial function and lipid profile in centrally overweight individuals: a randomised controlled trial.

The consumption of antioxidant-rich cooking oil such as red palm olein may be cardioprotective from the perspective of subclinical inflammation and endothelial function. Using a crossover design, we conducted a randomised controlled trial in 53 free-living high-risk abdominally overweight subjects, comparing the effects of incorporating red palm olein (with palm olein as control) in a supervised isocaloric 2100 kcal diet of 30% en fat, two-thirds (45 g/day) of which were derived from the test oil for a period of 6 weeks each. We did not observe a significant change in interleukin-6 (IL-6), in parallel with other pro-inflammatory (tumour necrosis factor-β, interleukin-1β, IL-1β, high sensitivity C-reactive protein, hsCRP) and endothelial function (soluble intercellular adhesion molecules, sICAM, soluble intravascular adhesion molecules, sVCAM) parameters. Interestingly, we observed a significant reduction in oxidised LDL levels (P < 0.0386) while on the red palm olein diet, together with the increase in plasma alpha tocopherol (P < 0.0002), alpha carotene (P < 0.0001) and beta carotene (P < 0.0001) concentrations compared with palm olein diet. Red palm olein did not improve subclinical inflammation and endothelial function despite profound increase in antioxidant levels. The positive improvement in oxidised LDL merits further attention in this group of subjects at risk of developing cardiovascular disease.

Effect of regular consumption of provitamin A biofortified staple crops on Vitamin A status in populations in low-income countries

Biofortification of staple crops with provitamin A (PVA) carotenoids is an innovative strategy for controlling vitamin A (VA) deficiency in low-income countries (LIC). Plant breeding programs have been successful in developing biofortified varieties of cassava, maize, and orange-fleshed sweet potatoes that contain amounts of PVA-carotenoids that have the potential to impact VA status in human populations. Nutrition studies indicate that beta-carotene in biofortified staple crops is converted efficiently to VA in the body. Randomized, controlled, community-based efficacy and effectiveness trials have been conducted to assess the effect of regular consumption of PVA-carotenoid biofortified staple crops on VA status. Results indicate that regular consumption of biofortified staple crops increases plasma beta-carotene concentrations consistently, but has a moderate effect, or no effect, on VA status, when assessed by serum retinol concentration, breast milk retinol concentration, or total body VA stores. Studies are currently underway to further investigate whether consumption of biofortified staple crops improves VA status in population subgroups at risk of VA deficiency, and to better understand how to optimize the biological impact of these interventions in resource-poor settings. Keywords: Beta-carotene, Biofortification, Bioavailability, Cassava, Maize, Provitamin A, Sweet potatoes, Vitamin A

Consuming High-Carotenoid Fruit and Vegetables Influences Skin Yellowness and Plasma Carotenoids in Young Women: A Single-Blind Randomized Crossover Trial

BackgroundConsumption of dietary carotenoids from fruits and vegetables (F/V) leads to accumulations in human skin, altering skin yellowness. The influence of the quantity of F/V consumed on skin yellowness and plasma carotenoid concentrations has not been examined previously. ObjectiveTo compare the influence of consuming high-carotenoid-containing F/V (HCFV) (176,425 μg beta carotene/wk) vs low-carotenoid F/V (LCFV) (2,073 μg beta carotene/wk) on skin yellowness and plasma carotenoid concentrations, over 4 weeks. Design and interventionA single-blind randomized controlled crossover trial from October 2013 to March 2014. Thirty women were randomized to receive 7 daily servings of HCFV or LCFV for 4 weeks. Following a 2-week washout period they followed the alternate intervention. Main outcome measuresSkin color (Commission Internationale de l'Eclairage L*a*b* color space, where L* represents skin lightness and positive values of a* and b* represent degrees of redness and yellowness, respectively) was assessed by reflectance spectroscopy in both sun-exposed and nonexposed skin areas. Fasting plasma carotenoids were determined by high-performance liquid chromatography, before and after each intervention period. Statistical analyses performedLinear mixed models were used to determine the HCFV and LCFV response on skin color and plasma carotenoids, adjusting for intervention order, time, and interaction between baseline differences and time. ResultsThere were no significant differences in mean daily fruit (P=0.42) and vegetable (P=0.17) intakes between HCFV and LCFV groups. Dietary alpha carotene, beta carotene, lutein, and beta cryptoxanthin intakes were significantly different between the two groups (P<0.01). Following HCFV there was a significantly greater increase in skin yellowness (b*) in both sun-exposed (P<0.001) and unexposed areas, (P<0.001), with no change in skin lightness (L*) or redness (a*). Significantly higher plasma alpha carotene (P=0.004), beta carotene (P=0.001), and lutein (P=0.028) concentrations were found following the HCFV intervention. Skin yellowness correlated with alpha carotene and beta carotene. ConclusionsSkin yellowness (b*) and fasting plasma carotenoid concentrations were significantly higher following HCFV than LCFV over 4 weeks.

Assessment of nutritional status in subjects of non‐MonaVie product users, before and after supplementation ő a longitudinal study (1044.20)

BACKGROUND: An antioxidant is a molecule that inhibits the oxidation of other molecules. Oxidation reactions can produce free radicals that cause various diseases. Antioxidants can inhibit the oxidation reactions and increase the body's immune system. To boost antioxidant levels, the human body relies on a healthy diet. However, very few people eat enough fruits and vegetables to provide their bodies with sufficient levels of antioxidants. To fill in the nutritional gaps of modern diets, many people turn to supplementation. OBJECTIVE: This is a continuation study in non users from the cross sectional study; we evaluated the improvement on skin and plasma levels of carotenoids in subjects of non MonaVie product users after 8‐week MonaVie juice consumption. METHODS: Total 33 non users from the cross sectional study were enrolled; 18 subjects having MonaVie juice formulated with proprietary carotenoid powder blend; 15 subject having MonaVie juice formulated with commercial carotenoid granules. All subjects had the weekly reflectance score measurements. and blood draw was taken at t=0 and 8 weeks. The plasma concentration of carotenoids were extracted and assayed by validated extraction and HPLC methods. RESULTS: The group having juice with proprietary carotenoid blend showed a good correlation between reflectance scores as well as the plasma beta carotene concentration (before r2 = 0.44 vs. after r2 = 0.44); while the group having juice with commercial carotenoids showed no correlation between reflectance scores and plasma beta carotene concentration (before r2 = 0.37 vs. after r2 = 0.095). CONCLUSION: The results show that both skin carotenoid levels and plasma carotenoid concentration were increased significantly after 8 week consumption of MonaVie juices; The juice with the proprietary carotenoid blend showed a good correlation between skin levels and plasma concentrations, suggesting a consistent and stable absorption rate and good bioavailability.

Fortification of vitamin A in a phytosterol enriched milk maintains plasma beta-carotene levels

The aim of the current study was to investigate if the supplementation of vitamin A via a phytosterol enriched low-fat milk could prevent the reduction of plasma beta-carotene concentrations than often occurs after plant sterols' or stanols' intake. A sample of 108 hypercholesterolaemic adults (40-60years old) was randomized to an enriched milk group that contained among other nutrients phytosterols (0.5g/100ml) and vitamin A (111μg/100ml) (EMG: n = 40), a placebo plain milk group (PMG: n = 37), and a control group (CG: n = 31) following their usual diet; the EMG and the PMG consumed 500ml milk per day and in order to ensure compliance with the intervention scheme, attended health and nutrition counselling sessions biweekly over a 3-month period. Dietary intake of vitamin A significantly increased in the EMG compared to the PMG and the CG (P < 0.001) and all groups significantly increased their vegetable consumption. However, no significant differences were found among groups regarding changes in dietary intake of beta-carotene and consumption of fruits. Regarding biochemical indices, total cholesterol, LDL-cholesterol and apolipoprotein-B decreased significantly within all study groups, with the decreases being significantly higher in the EMG compared to the CG (-25.4 vs. -9.9; -21.7 vs. -8.2 and -13.2 vs. -3.4mg/dl, respectively; P < 0.05). Plasma concentrations of beta-carotene did not change in any of the three groups. Extra fortification of a phytosterol enriched milk with vitamin A seems to be useful in maintaining plasma beta-carotene levels of hypercholesterolemic adults after consumption of 2.5g/d of phytosterols over a 3-month intervention period.

Associations of Soluble Fiber, Whole Fruits/Vegetables, and Juice with Plasma Beta-Carotene Concentrations in a Free-Living Population of Breast Cancer Survivors

Objective: Soluble fiber and the physical state of fruits/vegetables affect plasma ß-carotene concentrations; however, most of this research was conducted in laboratory-based settings. These analyses investigated the relationship between soluble fiber and juiced versus whole fruits/vegetables to plasma ß-carotene concentrations in a free-living population. Method: This cross-sectional analysis used 12-month follow-up data from the Women's Healthy Eating & Living Study (1995–2006), a study to improve diet in breast cancer survivors in the Western United States. The dietary nutrients considered in this analysis included intake of soluble fiber (g), ß-carotene from fruit/vegetable juice (mg), and ß-carotene from whole fruits/vegetables (mg). A linear regression model was used to assess the relationship of the variables to plasma ß-carotene concentrations. Results: Out of 3,088 women enrolled in the Women's Healthy Eating & Living Study, 2,397 women had complete data (mean age = 54). The final model accounted for approximately 49% of the explained variance in plasma ß-carotene concentrations. Fruit/vegetable juice had the largest positive relation to plasma ß-carotene concentrations (standardized parameter estimate = 0.23, p < 0.01), followed by whole fruits/vegetables (standardized parameter estimate = 0.09, p < 0.01). Conclusion: Soluble fiber may inhibit ß-carotene absorption; therefore, consumption of juice may increase plasma ß-carotene concentrations more than whole fruits/vegetables in free-living populations.

Lifestyle Characteristics and Dietary impact on Plasma Concentrations of Beta-carotene and Retinol

Mechanisms of dietary micronutrients and personal characteristics of the human body are intricately complicated. These mechanisms, however, can be easily interpreted through appropriate mathematical relationships. The present study aims to detect the statistically significant impact of personal characteristics and diet on plasma concentrations of retinol and beta-carotene using statistical modeling. The present analyses indicate that age, sex, smoking habit, quetelet, vitamin use, consumed calories, fiber, and dietary beta-carotene are statistically significant factors on plasma beta-carotene levels. On the other hand age, sex, smoking status, consumed fat, and dietary beta-carotene are significant factors on plasma retinol. These analyses indicate that changes in the variances of plasma beta-carotene and retinol are non-constant. Impacts of personal characteristics and dietary factors on human plasma concentrations of retinol and beta-carotene are explained based on mathematical relationships. These analyses support many earlier researches findings. However, the analyses also identify many additional casual factors that explain the means and variances of plasma beta-carotene and retinol, which earlier researches have not reported.

Effect of dietary fat supplementation during late pregnancy and first six months of lactation on maternal and infant vitamin A status in rural Bangladesh.

Dietary fat intake is extremely low in most communities with vitamin A deficiency. However, its role in vitamin A status of pregnant and lactating women is poorly understood. The aim of the study was to examine the effect of supplementing women with fat from mid-/late pregnancy until six months postpartum on their vitamin A status and that of their infants. Women recruited at 5-7 months of gestation were supplemented daily with 20 mL of soybean-oil (n = 248) until six months postpartum or received no supplement (n = 251). Dietary fat intake was assessed by 24-hour dietary recall at enrollment and at 1, 3 and 6 months postpartum. Concentrations of maternal plasma retinol, beta-carotene, and lutein were measured at enrollment and at 1, 3 and 6 months postpartum, and those of infants at six months postpartum. Concentration of breastmilk retinol was measured at 1, 3 and 6 months postpartum. The change in concentration of plasma retinol at three months postpartum compared to pregnancy was significantly higher in the supplemented compared to the control women (+0.04 vs -0.07 micromol/L respectively; p < 0.05). Concentrations of plasma beta-carotene and lutein declined in both the groups during the postpartum period but the decline was significantly less in the supplemented than in the control women at one month (beta-carotene -0.07 vs -0.13 micromol/L, p < 0.05); lutein -0.26 vs -0.49 micromol/L, p < 0.05) and three months (beta-carotene -0.04 vs -0.08 micromol/L, p < 0.05; lutein -0.31 vs -0.47 micromol/L, p < 0.05). Concentration of breastmilk retinol was also significantly greater in the supplemented group at three months postpartum than in the controls (0.68 +/- 0.35 vs 0.55 +/- 0.34 micromol/L respectively, p < 0.03). Concentrations of infants' plasma retinol, beta-carotene, and lutein, measured at six months of age, did not differ between the groups. Fat supplementation during pregnancy and lactation in women with a very low intake of dietary fat has beneficial effects on maternal postpartum vitamin A status.

18 Impact of dietary augmentation with dried whole fruit, vegetable and berry juice concentrates upon outcomes of periodontal therapy: a randomized controlled trial

M.M. Milward1, N. Ling-Mountford1, P. Weston1, G.E. Dallal2, J.B. Matthews1, S. De-Spirt3, W. Stahl3, I.L.C. Chapple1. 1Periodontal Research Group, College of Medical and Dental Sciences, The University of Birmingham, UK; 2Biostatistics Unit, USDA HNRC at Tufts University, Boston, MA, USA; 3Institut fuer Biochemie und Molekularbiologie I Heinrich-Heine-Universitaet, Duesseldorf, Germany E-mail: m.r.milward@bham.ac.uk Chronic periodontitis is the most prevalent chronic inflammatory disease of humans [1], a major cause of tooth loss [2] and an independent risk factor for systemic inflammatory diseases, such as atherogenic vascular disease [3], type-2 diabetes [4] and rheumatoid arthritis [5]. It is caused by a dysregulated inflammatory response to the microbial plaque biofilm, characterised by oxidative stress [6], and which fails to remove causative pathogens, creating a non-resolving inflammation that destroys the attachment of the teeth to jaw bone. Large epidemiological studies have demonstrated an inverse association between serum antioxidant micronutrient levels and periodontitis prevalence [7]. Therefore, the aim of this placebo-controlled, randomized, double blind trial, was to assess whether additional benefit could be obtained by use of dietary augmentation with dried whole fruit, vegetable and berry extracts (Juice Plus+®), employed during and after non-surgical periodontal therapy. Primary outcome measures were reductions in periodontal pocket depth (PPD) and gain in connective tissue attachment level (CAL) to teeth, 2-months following standard therapy. Test interventions were fruit/vegetable (FV, n = 16) and FV/berry (FVB, n = 15) verses placebo (PL, n = 17). Statistical analysis employed 2-tailed ANCOVA (baseline PPD and CAL as covariates) and interim data on 48 never smokers are reported. Plasma beta-carotene concentrations increased over the study period in FV and FVV groups (p 0.05), and were higher at 2-months in FV and FVV than PL (p < 0.006). Non-surgical therapy produced statistically significant improvements in PPD (FV = 0.86±0.4mm; FVB = 0.88±0.4mm; PL = 0.81±0.5mm) and for CAL (p < 0.0001). Despite such large improvements, additional benefit was seen for PPD with FV (p < 0.03) and FVB (p < 0.04) supplementation versus PL, and a trend towards additional gains in CAL with FV (p = 0.07). Thus, adjunctive antioxidant micronutrients (Juice Plus+®) may offer additional therapeutic benefit to standard non-surgical periodontal therapy. Support: NSA (TN, USA).

Preoperative levels of plasma micronutrients are related to endometrial cancer risk

To examine the relation between the plasma concentration of antioxidant micronutrients and endometrial cancer risk in Korean women. Hospital-based case-control study. Seven tertiary medical institutes in Korea. Incidence of 28 endometrial cancer cases were identified and 140 age-matched controls selected for the same period. Preoperative plasma concentrations of beta-carotene, lycopene, zeaxanthin plus lutein, retinol, alpha-tocopherol, and gamma-tocopherol were measured by reverse-phase, gradient high-pressure liquid chromatography. Conditional logistic regression was used to evaluate micronutrient effect after adjustment for body mass index (BMI), menopause, parity, oral contraceptive use, smoking status, and alcohol consumption status. Effect of micronutrients on endometrial cancer risk. The mean concentration of plasma beta-carotene (p=0.001), lycopene (p=0.008), zeaxanthin plus lutein (p=0.031), retinol (p=0.048), and gamma-tocopherol (p=0.046) were significantly lower in endometrial cancer patients than in controls. Plasma levels of beta-carotene (p for trend=0.0007) and lycopene (p for trend=0.007) were inversely associated with endometrial cancer risk across tertiles. Women in the highest tertile of plasma beta-carotene and lycopene had a 0.12-fold (95% confidence intervals (CIs) 0.03-0.48) and 0.15-fold (95% CIs 0.04-0.61) decreased risk of endometrial cancer compared to women in the lowest tertile, respectively. Other micronutrients such as zeaxanthin plus lutein (p for trend=0.142), retinol (p for trend=0.108), alpha-tocopherol (p for trend=0.322), and gamma-tocopherol (p for trend=0.087) showed no association with endometrial cancer risk. Plasma levels of beta-carotene and lycopene are inversely associated with the risk of endometrial cancer in Korean women.

Development and validation of a food frequency index using nutritional biomarkers in a sample of middle‐aged and older adults

An index of diet quality, which examines different aspects of a diet concurrently, may facilitate the identification of poor dietary habits in population sub-groups. The objectives of the present study were to develop a food frequency index (FFI) and to test its associations with nutritional biomarkers and nutrient intake. The study comprised a cross-sectional survey among 444 adults aged 55 years and older in Vienna, Austria, and a sub-sample of 226 subjects who provided fasting blood specimen. Data from a qualitative 28-item food-frequency questionnaire were used to develop the FFI. FFI scores were positively correlated with plasma concentrations of beta-carotene (r = 0.26), beta-cryptoxanthin (r = 0.31), zeaxanthin (r = 0.19), lutein (r = 0.21), phylloquinone (r = 0.19), 25-hydroxyvitamin D (r = 0.20), and serum high-density lipoprotein (HDL)-cholesterol (r = 0.24) and were negatively correlated with the ratio of total : HDL-cholesterol (r = -0.23). Sub-groups with higher FFI scores had, on average, lower intakes of total fat, saturated fat, and dietary cholesterol and higher intakes of total carbohydrates, dietary fibre, and most of the examined micronutrients. The FFI as a measure of diet quality has the ability to discern population sub-groups, with reasonable validity, into low- or high-risk dietary habits.

The total antioxidant capacity of the diet is an independent predictor of plasma β-carotene

To investigate the contribution of the total antioxidant capacity (TAC) of the diet to plasma concentrations of beta-carotene. Cross-sectional study. Department of Public Health and Department of Internal Medicine and Biomedical Sciences, University of Parma. A total of 247 apparently healthy adult men (n=140) and women (n=107). A medical history, a physical exam including height, weight, waist circumference and blood pressure measurements, a fasting blood draw, an oral glucose tolerance test and a 3-day food record. We observe a negative trend across quartiles of plasma beta-carotene for most biological variables clustering in the insulin resistance syndrome, as well as for traditional and new risk factors for type II diabetes and cardiovascular disease (CVD), including C-reactive protein and gamma-glutamyltranspeptidase (P<0.05). Regarding dietary characteristics, energy-adjusted intake of fat, fiber, fruits, vegetables, beta-carotene, vitamin C, vitamin E and dietary TAC significantly increased with increasing plasma beta-carotene (P<0.05), whereas alcohol intake decreased (P=0.013). Adjusted geometric means (95% confidence interval) of plasma beta-carotene significantly increased across quartiles of dietary TAC, even when single dietary antioxidants were considered in the model (QI=0.087 mg/dl (0.073-0.102); QII=0.087 mg/dl (0.075-0.103); QIII=0.114 mg/dl (0.098-0.132) and QIV=0.110 mg/dl (0.093-0.130); P for linear trend=0.026). When the population was divided on the basis of alcohol consumption, this trend was also observed in subjects drinking <20 g alcohol/day (P=0.034), but not in those with higher alcohol intake (P=0.448). Dietary TAC is an independent predictor of plasma beta-carotene, especially in moderate alcohol drinkers. This may explain, at least in part, the inverse relationship observed between plasma beta-carotene and risk of chronic diseases associated to high levels of oxidative stress (i.e., diabetes and CVD), as well as the failure of beta-carotene supplements alone in reducing such risk.

&lt;a name="home"&gt;&lt;/a&gt;Lycopene and ß-carotene protect in vivo iron-induced oxidative stress damage in rat prostate

It has been suggested that iron overload may be carcinogenic. In the present study, we evaluated the effect of plasma and prostate carotenoid concentration on oxidative DNA damage in 12-week-old Wistar rats treated with intraperitoneal (ip) ferric nitrilotriacetate (Fe-NTA) (10 mg Fe/kg). Plasma beta-carotene and lycopene concentrations were measured as a function of time after ip injection of carotenoids (10 mg kg(-1) day(-1) beta-carotene or lycopene) in rats. The highest total plasma concentration was reached 3 and 6 h after ip injection of lycopene or beta-carotene, respectively. After 5 days of carotenoid treatment, lycopene and beta-carotene were present in the 0.10-0.51 nmol/g wet tissue range in the prostate. Using a sensitive method to detected 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) by HPLC/EC, the level of 8-oxodGuo in rat prostate DNA was significantly higher (6.3 +/- 0.6 residues/10(6) dGuo) 3 h after Fe-NTA injection compared with control rats (1.7 +/- 0.3 residues/10(6) dGuo). Rats supplemented with lycopene or beta-carotene for 5 days prior to Fe-NTA treatment showed a reduction of about 70% in 8-oxodGuo levels to almost control levels. Compared with control rats, the prostate of Fe-NTA-treated animals showed a 78% increase in malondialdehyde accumulation. Lycopene or beta-carotene pre-treatment almost completely prevented lipid damage. Epidemiological studies have suggested a lower risk of prostate cancer in men reporting a higher consumption of tomato products. However, before associating this effect with tomato sauce constituents, more information is required. The results described here may contribute to the understanding of the protective effects of carotenoids against iron-induced oxidative stress.

The physiological and production effects of increased dietary intake of vitamins E and C in feedlot cattle challenged with bovine herpesvirus 11

The physiological and production effects of feeding additional vitamin E and ruminally protected vitamin C were examined in cattle challenged with bovine herpesvirus 1 (BHV 1). Forty-eight individually penned 6-mo-old Angus and Angus crossbred heifer calves with a mean BW of 151 kg were allocated randomly to four diets in a 2 x 2 factorial arrangement of treatments. Pelleted diets provided either 15 or 185 IU/kg of DM of vitamin E, with or without 3.7 g of ruminally protected vitamin C/kg of DM. Blood samples were taken at start of the experiment and at wk 4, 5, and 6. At the start of wk 5, half of each of the dietary groups was challenged with BHV 1. Feeding additional vitamin E was associated with greater (P < 0.001) mean plasma alpha-tocopherol. In contrast, feeding ruminally protected vitamin C was not associated with greater (P = 0.59) mean plasma ascorbate concentration; however, feeding ruminally protected vitamin C was associated with lower (P = 0.03) mean blood total superoxide dismutase (Cu/Zn SOD and Mn SOD) concentration. Calves fed additional vitamin E had greater (P = 0.05) mean plasma beta-carotene concentrations. There were interactions between dietary intake of vitamins E and C with respect to serum ceruloplasmin concentration (P = 0.01) and G:F (P = 0.05). Bovine herpesvirus 1 challenge was associated with lower white cell count (P = 0.007), lymphocyte count (P < 0.001), and DMI (P = 0.03). Feeding additional vitamin E to calves challenged with BHV 1 was associated with a lower (P = 0.03) serum ceruloplasmin concentration. There was a non-significant trend towards an interaction (P = 0.06) between the feeding of vitamins E and C, with virus-challenged calves fed additional vitamin E alone having greater plasma retinol concentrations. The feeding of vitamins E and/or C in calves challenged with BHV 1 was associated with alterations in the concentrations of other antioxidants. More severe disease may have translated these cellular effects to changes in health and performance.

Smoking during Pregnancy and Plasma Concentrations of beta-Carotene and alpha-Tocopherol in the Immediate Postpartum Period in Brazilian Women

This study investigated the relationship between plasma concentrations of beta-carotene and the alpha-tocopherol/lipid ratio, and smoking in 233 postpartum women, from July to November 2002, in the city of Joinville, Brazil. Thirty-seven percent (37%) of the women included in this study had low concentrations of alpha-tocopherol (< 11.63 micromol/L) and 61% of the women presented low concentrations of beta-carotene (< 0.39 micromol/L). Multivariate regression analysis investigated the relationship between smoking and the concentration of the vitamins, adjusting by confounding variables. The final regression model showed inverse associations between beta-carotene concentrations and smoking (p = 0.036), and beta-carotene concentrations and triglyceride levels (p = 0.021). There was an association between the plasma alpha-tocopherol/lipid ratio and per capita income (p = 0.003), but no association with smoking. We advise further studies to evaluate the impact of smoking and oxidative stress on the concentrations of these vitamins.

Effects of Dietary Taurocholate, Fat and Protein on the Storage and Metabolism of Dietary beta-Carotene and alpha-Tocopherol in Ferrets

Dietary factors affecting tissue storage of beta-carotene (BC), alpha-tocopherol (alpha-T), and retinol (ROL) in mammals include taurocholate, protein, and fat. Few studies have examined the effects of these factors on the storage of BC, retinyl esters, and alpha-T in a mammalian system that is similar to humans. The main objective of the study was to investigate the effects of taurocholate (TC), fat, and protein on the absorption and metabolism of BC and alpha-T in ferret tissues. Three 4-week experiments were conducted using groups of 5-6 ferrets per treatment. All diets contained 0.2% BC. In Experiment 1, taurocholate was fed at concentrations of 0, 0.5, or 1%. Effects of two concentrations of dietary fat (6 and 23%) and three concentrations of protein (10, 20, and 40%) were also studied in Experiments 2 and 3, respectively. Tissues were analyzed for BC, retinoids, and alpha-T by high-pressure liquid chromatography (HPLC). Taurocholate enhanced hepatic and plasma concentrations of BC (2.3- to 3-fold), retinyl palmitate [(RP) 3.2- to 9.5-fold], retinyl stearate [(RS) 2.9- to 6- fold], and hepatic alpha-T (6- to 13- fold) at p < 0.05. High-fat diets elevated hepatic BC, RP, RS, and retinyl linoleate (RL) concentrations (2- to 3.6-fold, p < 0.05). In contrast, high-protein diets lowered hepatic RL 1.8-fold and alpha-T 8-fold (p < 0.05). Our results indicate the importance of taurocholate, fat, and protein in achieving adequate levels of vitamins A and E in mammals.

Increased intake of fruit and vegetables and a low‐fat diet, with and without low‐fat plant sterol‐enriched spread consumption: effects on plasma lipoprotein and carotenoid metabolism

Regular intake of plant sterol (phytosterol)-enriched foods enhances the cholesterol lowering effect of diets. One side effect associated with plant sterol consumption is a modest reduction in plasma carotenoid concentrations. This study investigated the effect of consuming a low-fat National Cholesterol Education Programme (NCEP) Step 1 diet, including a low-fat plant sterol ester (PSE)-enriched spread on cholesterol metabolism to determine if specific dietary advice to increase daily fruit and vegetable intake could prevent reduced plasma carotenoid concentrations. In this randomised, crossover double-blind trial, 48 hypercholesterolaemic men received 21 g day(-1) of a low-fat PSE-enriched spread or placebo for 3 weeks, interrupted by 3 weeks washout. Individuals also adhered to a NCEP Step 1 diet and repeated 3-day food diaries monitored adherence. Specific advice was provided to increase dietary fruit and vegetable intakes. Fasting blood samples were collected at pre- and post-intervention for lipoprotein and carotenoid analysis. Plasma total and low-density lipoprotein (LDL) cholesterol concentrations were significantly (P <0.05) reduced, by 4.6 and 7.1%, respectively, after the PSE-enriched low-fat spread. Plasma apo B concentrations were significantly (P <0.0005) lower after the PSE spread. PSE consumption was also associated with significantly (P <0.05) lower total plasma beta-carotene concentrations, but this change was not significant after lipid standardisation. PSE consumption had no effect on retinol, alpha-carotene, gamma-tocopherol, alpha-tocopherol, lutein, zeaxanthin, beta-crypyoxanthin or lycopene concentrations. Dietary advice to increase daily fruit and vegetable consumption may be effective in preventing a reduction in plasma carotenoid concentrations previously associated with PSE consumption. Further, PSE incorporated in a low-fat spread and consumed as part of a NCEP Step 1 diet are effective in reducing total and LDL cholesterol.