The Association between Circulating Carotenoids and Risk of Breast Cancer: A Systematic Review and Dose-Response Meta-Analysis of Prospective Studies.

Carotenoids appear to have anticancer effects. Prospective evidence for the relation between serum carotenoids and breast cancer is controversial. The present systematic review and meta-analysis aimed to investigate the link between circulating carotenoids and the risk of breast cancer. We performed a systematic search of PubMed, Scopus, and Web of Science up to 30 November, 2022. Prospective studies on adults aged ≥18 y that have reported risk estimates for the association between circulating carotenoids and breast cancer risk were considered. Study quality was assessed using the Newcastle-Ottawa Scale. A random-effects model was used for combining studies' risk estimates. Dose-response relations were explored through a 1-stage random-effects model. Fifteen publications (17 nested case-control studies and 1 cohort study) with 20,188 participants and 7608 cases were included. We observed an inverse association between the highest level of circulating total carotenoids (relative risk [RR]: 0.76; 95% confidence interval [CI]: 0.62, 0.93; n = 8), α-carotene (RR: 0.77; 95% CI: 0.68, 0.87; n = 13), ß-carotene (RR: 0.80; 95% CI: 0.65, 0.98; n = 15), ß-cryptoxanthin (RR: 0.85; 95% CI: 0.74, 0.96; n = 11), lycopene (RR: 0.86; 95% CI: 0.76, 0.98; n = 13), and lutein (RR: 0.70; 95% CI: 0.52, 0.93; n = 6) and the risk of breast cancer compared with the lowest level. Additionally, each 10 µg/dL of total carotenoids, α-carotene, ß-carotene, and ß-cryptoxanthin was associated with 2%, 22%, 4%, and 10% lower risk of breast cancer, respectively. This relationship was stronger at lower levels of total carotenoids and ß-cryptoxanthin. The certainty of evidence was rated from very low to low. Most studies were performed among Western nations, which should be acknowledged for extrapolation of findings. Total circulating carotenoids, α-carotene, ß-carotene, ß-cryptoxanthin, lycopene, and lutein seem to be related to a decreased risk of breast cancer. Our findings could have practical importance for public health. This study was registered at PROSPERO as CRD42023434983.

HDL is the primary transporter for carotenoids from liver to retinal pigment epithelium in transgenic ApoA-I-/-/Bco2-/- mice.

Supplementation with antioxidant carotenoids is a therapeutic strategy to protect against age-related macular degeneration (AMD); however, the transport mechanism of carotenoids from the liver to the retina is still not fully understood. Here, we investigate if HDL serves as the primary transporter for the macular carotenoids. ApoA-I, the key apolipoprotein of HDL, was genetically deleted from BCO2 knockout (Bco2-/-) mice, a macular pigment mouse model capable of accumulating carotenoids in the retina. We then conducted a feeding experiment with a mixed carotenoid chow (lutein:zeaxanthin:ß-carotene = 1:1:1) for one month. HPLC data demonstrated that the total carotenoids were increased in the livers but decreased in the serum, retinal pigment epithelium (RPE)/choroids, and retinas of ApoA-I-/-/Bco2-/- mice compared to Bco2-/- mice. In detail, ApoA-I deficiency caused a significant increase of ß-carotene but not lutein and zeaxanthin in the liver, decreased all three carotenoids in the serum, blocked the majority of zeaxanthin and ß-carotene transport to the RPE/choroid, and dramatically reduced ß-carotene and zeaxanthin but not lutein in the retina. Furthermore, surface plasmon resonance spectroscopy (SPR) data showed that the binding affinity between ApoA-I and ß-carotene â‰« zeaxanthin > lutein. Our results show that carotenoids are transported from the liver to the eye mainly by HDL, and ApoA-I may be involved in the selective delivery of macular carotenoids to the RPE.

A Biological Index to Screen Multi-Micronutrient Deficiencies Associated with the Risk to Develop Dementia in Older Persons from the Community.

BACKGROUND: Low blood status in several nutritional compounds, including long-chain omega-3 fatty acids (LC n-3 PUFA), carotenoids, and vitamin D, have been associated with a higher risk to develop dementia. Nutritional deficiencies may potentiate each other regarding dementia risk; yet the association of multiple nutritional deficiencies with dementia has been little explored. OBJECTIVE: To develop an index of micronutritional biological status (MNBS) for the screening of multi-micronutritional deficiencies associated with the risk of dementia in a prospective population-based cohort of older persons. METHODS: We included participants from the Bordeaux Three-City study, who were free of dementia at baseline, had blood measurements of LC n-3 PUFA, carotenoids, and 25(OH)D, and who were followed for up to 18 years for dementia. We used penalized splines in Cox models to model dose-response relationships of each nutritional component with the risk of dementia and construct a risk index. RESULTS: 629 participants with an average age of 73.1 years were included in the study. Each increase of 1 SD of the MNBS index was associated with a 46%higher risk of dementia (HR = 1.46, 95%CI 1.23; 1.73). Participants with highest index ([mean+1SD; max]) had a 4-fold increased risk of dementia compared with participants with a low index ([min; mean-1SD]) (HR = 4.17, 95%CI 2.30; 7.57). CONCLUSION: This index of assessment of micronutritional biological status is a practical tool that may help identify populations with inadequate nutritional status, screen eligible individuals for nutritional prevention in primary care, or for supplementation in preventive trials of dementia.

The Gut Microbiome Is Associated with Circulating Dietary Biomarkers of Fruit and Vegetable Intake in a Multiethnic Cohort.

BACKGROUND: Results from observational studies suggest high diet quality favorably influences the human gut microbiome. Fruit and vegetable consumption is often a key contributor to high diet quality. OBJECTIVE: To evaluate measures of gut bacterial diversity and abundance in relation to serum biomarkers of fruit and vegetable intake. DESIGN: Secondary analysis of cross-sectional data. PARTICIPANTS AND SETTING: Men and women from Los Angeles, CA, and Hawai'i who participated in the Multiethnic Cohort-Adiposity Phenotype Study from 2013 to 2016 (N = 1,709). MAIN OUTCOME MEASURES: Gut microbiome diversity and composition in relation to dietary biomarkers. STATISTICAL ANALYSIS: Carotenoid (beta carotene, alpha carotene, cryptoxanthins, lutein, lycopene, and zeaxanthin), tocopherol (α, ß + γ, and δ), and retinol concentrations were assessed in serum. The α and ß diversity and composition of the gut microbiome were classified based on 16S rRNA gene sequencing of bacterial DNA from self-collected fecal samples. Global differences in microbial community profiles in relation dietary biomarkers were evaluated using multivariable permutational analysis of variance. Associations of α diversity (Shannon index), ß diversity (weighted and unweighted UniFrac) with center log-ratio-transformed phyla and genera abundances were evaluated using linear regression, adjusted for covariates. RESULTS: Increasing total carotenoid, beta carotene, alpha carotene, cryptoxanthin, and lycopene concentrations were associated with higher gut bacterial diversity (Shannon Index) (P < 0.001). Total tocopherol, α-tocopherol, and δ-tocopherol concentrations contributed significantly to more than 1% of the microbiome variation in gut bacterial community: total tocopherol: 1.74%; α-tocopherol: 1.70%; and δ-tocopherol: 1.16% (P < 0.001). Higher total carotenoid was associated with greater abundance of some genera relevant for microbial macronutrient metabolism (P < 0.001). CONCLUSIONS: Objective biomarkers of fruit and vegetable intake, particularly carotenoids, were favorably associated with gut bacterial composition and diversity in this multiethnic population. These observations provide supportive evidence that fruit and vegetable intake is related to gut bacterial composition; more work is needed to elucidate how this influences host health.

Plasma Carotenoids and Premenstrual Symptoms in a Multi-Ethnic Population of Young Women.

Premenstrual symptoms are experienced by most women of reproductive age, but effective therapies are limited. Carotenoids may have an attenuating effect on premenstrual symptoms; however, studies to date are equivocal. The objective of the present study was to examine the association between plasma concentrations of seven carotenoids and premenstrual symptom severity in 553 women from the Toronto Nutrigenomics and Health study. Participants provided information on fifteen common premenstrual symptoms and severities. Each participant completed a General Health and Lifestyle Questionnaire and provided a fasting blood sample from which plasma carotenoid concentrations were measured. Multinomial logistic regressions were used to determine associations between plasma carotenoid concentrations and premenstrual symptom severity. Beta-cryptoxanthin was associated with moderate/severe increased appetite for women in the highest compared to the lowest tertile (OR: 2.33; 95% CI: 1.39, 3.89). This association remained significant after adjusting for multiple comparisons. There were no observed associations between other plasma carotenoids and any premenstrual symptoms. In summary, higher concentrations of beta-cryptoxanthin were associated with an increased appetite as a premenstrual symptom, but no associations were observed for any other carotenoid and for any other symptom.

A pilot study of the effects of crocin on high-density lipoprotein cholesterol uptake capacity in patients with metabolic syndrome: A randomized clinical trial.

A randomized clinical trial high-density lipoprotein (HDL) cholesterol uptake capacity (CUC) is reduced in patients with metabolic syndrome (MetS). We have assessed the effect of crocin supplementation on HDL CUC in patients with MetS. Forty-four subjects with MetS were randomly allocated to one of two groups: one group received placebo and the other group received crocin at a dose of 30 mg (two tablets of 15 mg per day) for 8 weeks. Serum biochemical parameters were measured using an AutoAnalyzer BT3000 (BioTechnica). The modified CUC method is a cell free, simple, and high-throughput assay that used to evaluate HDL CUC of serum samples. The decision tree analysis was undertaken using JMP Pro (SAS) version 13. The mean age of the crocin and placebo groups were 38.97 ± 13.33 and 43.46 ± 12.77 years, respectively. There was a significant increase in serum HDL CUC in the crocin group compared to that of the placebo group in patients with MetS (p-value< 0.05). The decision tree analysis showed that serum HDL functionality was more important variable than HDL-C level in predicting patients with hypertension at baseline (p-value < 0.05). Crocin administration (30 mg for a period of 8 weeks) was found to improve serum HDL CUC in patients with MetS. TRIAL REGISTRATION: IRCT2013080514279N1.

Mediterranean Diet Affects Blood Circulating Lipid-Soluble Micronutrients and Inflammatory Biomarkers in a Cohort of Breast Cancer Survivors: Results from the SETA Study.

Breast cancer (BC) is a major public health concern and substantial research has shown that adhering to a healthy dietary pattern, such as the Mediterranean Diet (MD), may prevent the onset of cancer and BC relapses. This study aims at specifically investigating the association of MD with circulating dietary-related biomarkers in a cohort of BC survivors. Eighty patients (mean age of 54.9 ± 10.6) with a histologically confirmed diagnosis of BC who had not received any pharmacological or radiotherapy treatment for at least two months were enrolled. Fasting serum lipid-soluble vitamins (retinol, tocopherol), plant pigments (ß-carotene, lutein + zeaxanthin, cryptoxanthin, lycopene), inflammatory and oxidative stress markers (ceruloplasmin; haptoglobin; paraoxonases; reactive oxygen molecule; thiol groups, Ferric reducing antioxidant power), and cardiometabolic parameters (body mass index (BMI); glucose; insulin; HOMA-IR; total cholesterol; LDL-cholesterol; HDL-cholesterol; triglycerides) were analyzed. Adherence to the MD was assessed through the Mediterranean Diet Score (MDS) questionnaire. Fasting blood samples were collected for the evaluation of selected biomarkers. MDS resulted positively correlated with ß-carotene (r 0.331; p < 0.01) and lycopene (r 0.274; p < 0.05) and negatively with retinol (r -0.346; p < 0.05). Among the investigated inflammatory biomarkers, MDS was only correlated with antioxidant capacity (r 0.256; p < 0.05), while none of the investigated cardiometabolic parameters were significantly correlated with this index. The strong significant correlation between ß-carotene and MDS encourages us to consider this pro-vitamin as a putative biomarker to take into account for evaluating the adherence to the MD.

Changes in Lutein Status Markers (Serum and Faecal Concentrations, Macular Pigment) in Response to a Lutein-Rich Fruit or Vegetable (Three Pieces/Day) Dietary Intervention in Normolipemic Subjects.

Lutein is mainly supplied by dietary fruit and vegetables, and they are commonly jointly assessed in observational and interventional studies. Lutein bioavailability and health benefits depend on the food matrix. This study aimed to assess the effect of dietary intervention with lutein-rich fruit or vegetables on lutein status markers, including serum and faecal concentrations (by high pressure liquid chromatography), dietary intake (24 h recalls ×3), and macular pigment optical density (MPOD) and contrast threshold (CT) as visual outcomes. Twenty-nine healthy normolipemic subjects, aged 45-65 y, consumed 1.8 mg lutein/day supplied from fruits (14 subjects, 500 g/day of oranges, kiwi and avocados) or vegetables (15 subjects, 180 g/day of green beans, pumpkin, and sweet corn) for four weeks. Serum lutein concentration increased by 37%. The effect of the food group intervention was statistically significant for serum lutein+zeaxanthin concentration (p = 0.049). Serum α- and ß-carotene were influenced by food type (p = 0.008 and p = 0.005, respectively), but not by time. Serum lutein/HDL-cholesterol level increased by 29% (total sample, p = 0.008). Lutein+zeaxanthin/HDL-cholesterol increased, and the intervention time and food group eaten had an effect (p = 0.024 and p = 0.010, respectively) which was higher in the vegetable group. The MPOD did not show variations, nor did it correlate with CT. According to correlation matrixes, serum lutein was mainly related to lutein+zeaxanthin expressed in relation to lipids, and MPOD with the vegetable group. In faecal samples, only lutein levels increased (p = 0.012). This study shows that a relatively low amount of lutein, supplied by fruit or vegetables, can have different responses in correlated status markers, and that a longer intervention period is needed to increase the MPOD. Therefore, further study with larger sample sizes is needed on the different responses in the lutein status markers and on food types and consumption patterns in the diet, and when lutein in a "pharmacological dose" is not taken to reduce a specific risk.

Higher circulating α-carotene was associated with better cognitive function: an evaluation among the MIND trial participants.

There is emerging evidence linking fruit and vegetable consumption and cognitive function. However, studies focusing on the nutrients underlying this relationship are lacking. We aim to examine the association between plasma nutrients and cognition in a population at risk for cognitive decline with a suboptimal diet. The Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) trial is a randomized controlled intervention that examines the effects of the MIND diet to prevent cognitive decline. The primary outcome is global cognition. A multivariate linear model was used to investigate the association between blood nutrients and global and/or domain-specific cognition. The model was adjusted for age, sex, education, study site, smoking status, cognitive activities and physical activities. High plasma α-carotene was associated with better global cognition. Participants in the highest tertile of plasma α-carotene had a higher global cognition z score of 0⋅17 when compared with individuals in the lowest tertile (P 0⋅002). Circulating α-carotene levels were also associated with higher semantic memory scores (P for trend 0⋅007). Lutein and zeaxanthin (combined) was positively associated with higher semantic memory scores (P for trend 0⋅009). Our study demonstrated that higher α-carotene levels in blood were associated with higher global cognition scores in a US population at risk for cognitive decline. The higher α-carotene levels in blood reflected greater intakes of fruits, other types of vegetables and lesser intakes of butter and margarine and meat. The higher circulating levels of lutein plus zeaxanthin reflected a dietary pattern with high intakes of fruits, green leafy, other vegetables and cheese, and low consumption of fried foods. Objective nutrient markers in the blood can better characterize dietary intake, which may facilitate the implementation of a tailored dietary intervention for the prevention of cognitive decline.

Associations of Subtype and Isomeric Plasma Carotenoids with Prostate Cancer Risk in Low-Income African and European Americans.

BACKGROUND: Various carotenoids in circulation, including isomers, may have different influences on cancer risk. METHODS: We conducted a nested case-control study including 343 incident prostate cancer cases and 640 controls individually matched on age, race, study site, and time of blood collection. Carotenoids investigated were carotene, cryptoxanthin, lycopene, dihydrolycopene, lutein, anhydrolutein, and zeaxanthin, including α versus ß configurations and cis versus trans isomers. General linear model and conditional logistic regression were applied to evaluate associations for prostate cancer risk, with adjustment for potential confounders. We conducted additional analyses with further stratification by race, multivitamin use, and smoking status. RESULTS: Case-control differences were found in carotenoid subtype levels, although not all reached the multiple comparison adjusted threshold for significance. Plasma lycopene [ORT1 vs. T3 = 0.51; 95% confidence interval (CI), 0.29-0.87; P trend = 0.014], dihydrolycopene (ORT1 vs. T3 = 0.37; 95% CI, 0.18-0.74; P trend = 0.006), and cis-anhydrolutein (ORT1 vs. T3 = 0.57; 95% CI, 0.33-0.96; P trend = 0.037) were inversely, while ß-trans-carotene (ORT1 vs. T3 = 2.13; 95% CI, 1.32-3.43; P trend = 0.002) and trans-lutein (ORT1 vs. T3, 1.86; 95% CI, 1.20-2.88; P trend = 0.006) were positively associated with prostate cancer risk. Stratified analyses showed inverse associations of lycopene, dihydrolycopene, and cis-anhydrolutein with prostate cancer risk in subjects without multivitamin use; lycopene and dihydrolycopene in African-Americans and current smokers; and dihydrolycopene in nonsmokers. Positive associations of ß-trans-carotene and trans-lutein were observed in African-Americans, nonsmokers, and multivitamin users. CONCLUSIONS: The associations of carotenoids with risk of prostate cancer differed by carotenoid subtypes. IMPACT: Public health recommendations on carotenoid intakes for prostate cancer prevention should take subtypes and isomers into consideration.

Plasma Lutein, a Nutritional Biomarker for Development of Advanced Age-Related Macular Degeneration: The Alienor Study.

Lutein and zeaxanthin may lower the risk of age-related macular degeneration (AMD). We evaluated the associations of plasma lutein and zeaxanthin with the incidence of advanced AMD in the Alienor study (Antioxydants Lipides Essentiels Nutrition et Maladies Oculaires). Alienor study is a prospective population-based cohort of 963 residents of Bordeaux, France, who were 73 years or older at baseline (2006-2008). The present study included 609 participants with complete ophthalmologic and plasma carotenoids data. Examinations were performed every two years over an eight-year period (2006 to 2017). Plasma lutein and zeaxanthin were determined at baseline from fasting blood samples using high-performance liquid chromatography. Cox proportional hazard models were used to assess associations between plasma lutein, zeaxanthin, and their (total cholesterol (TC) + triglycerides (TG)) ratios with AMD. Among the 609 included participants, 54 developed advanced incident AMD during a median follow-up time of 7.6 years (range 0.7 to 10.4). Participants with higher plasma lutein had a reduced risk for incident advanced AMD in the fully adjusted model (HR = 0.63 per 1-SD increase (95% CI, 0.41-0.97), p = 0.03). A similar association was observed using the lutein/(TC + TG) ratio (HR = 0.59 (95% CI, 0.39-0.90), p = 0.01). No associations were evidenced for other carotenoids. Higher plasma lutein was associated with a 37% reduced risk of incident advanced AMD.

The Associations of Plasma/Serum Carotenoids with Alzheimer's Disease: A Systematic Review and Meta-Analysis.

BACKGROUND: Multiple lines of evidence indicate protective effects of carotenoids in Alzheimer's disease (AD). However, previous epidemiological studies reported inconsistent results regarding the associations between carotenoids levels and the risk of AD. OBJECTIVE: Our study aims to evaluate the associations of six major members of carotenoids with the occurrence of AD by conducting a systematic review and meta-analysis. METHODS: Following PRISMA guidelines, a comprehensive literature search of PubMed, Web of Science, Ebsco, and PsycINFO databases was conducted, and the quality of each included studies was evaluated by a validated scoring systems. Standardized mean differences (SMD) with 95% confidence intervals (CI) were determined by using a random effects model. Heterogeneity was evaluated by I2 statistics. Publication bias was detected using funnel plots and Egger's test. RESULTS: Sixteen studies, with 10,633 participants were included. Pooled analysis showed significantly lower plasma/serum levels of lutein (SMD = -0.86, 95% CI: -1.67 to -0.05, p = 0.04) and zeaxanthin (SMD = -0.59; 95% CI: -1.12 to -0.06, p = 0.03) in patients with AD versus cognitively intact controls, while α-carotene (SMD = 0.21, 95% CI: -0.68 to 0.26, p = 0.39), ß-carotene (SMD = 0.04, 95% CI: -0.57 to 0.65, p = 0.9), lycopene (SMD = -0.12, 95% CI: -0.96 to 0.72, p = 0.78), and ß-cryptoxanthin (SMD = -0.09, 95% CI: -0.83 to 0.65, p = 0.81) did not achieve significant differences. CONCLUSION: Of six major members of carotenoids, only lutein and zeaxanthin concentrations in plasma/serum were inversely related to the risk of AD. More high-quality longitudinal studies are needed to verify these findings.

Analysis of Repeated Measurements of Serum Carotenoid Levels and All-Cause and Cause-Specific Mortality in Japan.

Importance: The associations of levels of diverse serum carotenoids ascertained via repeated measurements with all-cause, cancer, and cardiovascular disease (CVD) mortality risk have not been considered in previous prospective studies. Objective: To investigate the association between repeated measurement of serum carotenoid levels and all-cause and cause-specific mortality risk. Design, Setting, and Participants: This cohort study's baseline data were collected using information from physical examinations from 1990 to 1999. Eligible participants were followed up until December 2017, with a median (interquartile range) follow-up period of 22.3 (15.5-25.3) years. Included individuals were age 40 years or older at the baseline data collection, were residents of the study site in the town of Yakumo, Hokkaido, Japan, and participated in a physical examination at least once from 1990 to 1999. Among eligible participants, after excluding 332 individuals, 3116 individuals were included in the analysis. Data analysis was conducted in April 2020. Exposures: Repeated measurements of 6 serum carotenoid levels and 4 associated indices. Main Outcomes and Measures: All-cause, cancer, and CVD mortality, categorized by International Classification of Diseases, Ninth Revision and International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes, were recorded. A time-dependent Cox regression model was performed to examine associations between time-varying serum carotenoid levels and mortality. Results: Among 3116 individuals who received physical examinations, the mean (SD) age was 54.7 (10.6) years and 1883 (60.4%) were women. During the follow-up period, 762 deaths from all causes, 253 deaths from cancer, and 210 deaths from CVD were ascertained. In a time-dependent Cox regression analysis, for every 25% higher serum levels of total carotenoids, risks were statistically significantly lower for all-cause mortality (hazard ratio [HR], 0.85; 95% CI, 0.82-0.87; P < .001), cancer mortality (HR, 0.82; 95% CI, 0.78-0.87; P < .001), and CVD mortality (HR, 0.86; 95% CI, 0.81-0.91; P < .001). Using only baseline measures, for every 25% higher serum levels of total carotenoids, risks were also statistically significantly lower for all-cause mortality (HR, 0.92; 95% CI, 0.89-0.95; P < .001), cancer mortality (HR, 0.87; 95% CI, 0.83-0.93; P < .001), and CVD mortality (HR, 0.93; 95% CI, 0.88-0.99; P = .03) but with larger HRs than those associated with repeated measurements. Conclusions and Relevance: This study found that higher levels of serum carotenoids in analysis using repeated measurements were associated with significantly lower all-cause and cause-specific mortality over a follow-up period of 25 years.

Fruit and vegetable intake is inversely associated with perceived stress across the adult lifespan.

BACKGROUND & AIMS: Poor nutritional habits are linked to higher perceived stress, but the relationship between fruit and vegetable (FV) intake and stress is uncertain. The primary aim of this cross-sectional study was to explore the relationship between FV intake and perceived stress in a population-based cohort of men and women aged ≥25 years from the Australian Diabetes, Obesity and Lifestyle (AusDiab) Study. A secondary aim was to investigate the relationship between serum carotenoids, biomarkers of FV intake, and perceived stress. METHODS: In Australian men and women, dietary intake was assessed using a Food Frequency Questionnaire in 1999-2000 (n = 8689). Perceived stress was assessed using a validated Perceived Stress Questionnaire [PSQ index values ranging from 0 (lowest) to 1 (highest)]. Serum carotenoids were measured in a subset of participants (n = 1187) using high-performance liquid chromatography. Multivariable-adjusted linear and logistic regression were performed to investigate the associations between FV intake and perceived stress. RESULTS: Mean age of participants was 47.4 (SD 14.1) years (49.8% females). Participants with the highest intakes of FV had 10% lower PSQ index values than those with the lowest intake [Q4: 0.27 ± 0.004 vs. Q1: 0.30 ± 0.004 (mean ± SE), p = 0.004]. Similar associations were found for fruits and vegetables, analysed separately. In subgroup analyses higher FV intake was associated with lower perceived stress in the middle-aged adults [≥45-<65 years (p = 0.004)], but not in the younger (<45 years) and older participants (≥65 years). Higher FV intake was also significantly associated with lower perceived stress in men (p = 0.009) and women (p = 0.012), separately. Serum carotenoid levels were inversely associated with perceived stress before, but not after adjusting for age and other confounding factors. CONCLUSION: In Australian adults, higher FV intake was associated with lower perceived stress, particularly in the middle-aged adults. These findings support current recommendations that fruit and vegetables are essential for health and well-being.

Association between Serum Concentration of Carotenoid and Visceral Fat.

Consumption of fruits and vegetables rich in carotenoids has been widely reported to prevent cardiovascular diseases. However, the relationship between serum carotenoid concentrations and visceral fat area (VFA), which is considered a better predictor of cardiovascular diseases than the body-mass index (BMI) and waist circumference, remains unclear. Therefore, we examined the relationship in healthy individuals in their 20s or older, stratified by sex and age, to compare the relationship between serum carotenoid concentrations and VFA and BMI. The study was conducted on 805 people, the residents in Hirosaki city, Aomori prefecture, who underwent a health checkup. An inverse relationship between serum carotenoid concentrations and VFA and BMI was observed only in women. In addition, the results were independent of the intake of dietary fiber, which is mainly supplied from vegetables as well as carotenoids. This suggests that consumption of a diet rich in carotenoids (especially lutein and beta-carotene) is associated with lower VFA, which is a good predictor of cardiovascular disease, especially in women. This study is the first to comprehensively evaluate the association between serum carotenoid levels and VFA in healthy individuals.

Carotenoid status in type 2 diabetes patients with and without retinopathy.

Diabetic retinopathy (DR) is one of the leading causes of blindness. Carotenoids are plant-derived pigments required for general health and particularly for vision. In this study, we evaluated the dietary intake and blood carotenoid levels of type 2 diabetes (T2D) patients with and without DR. A cross-sectional case-control study was conducted among 151 age-matched controls and 344 T2D patients, of which 194 had DR and 150 had no DR (NDR). After a complete ophthalmic examination, the demographic, anthropometric and clinical profiles were obtained. Carotenoids in the plasma were measured by HPLC and dietary intakes were obtained using a food frequency questionnaire. The mean plasma levels of carotenoids (except γ-carotene) were significantly lower in the DR group compared to the Control and NDR groups. The dietary intakes of zeaxanthin, lycopene, α-carotene and ß-carotene were significantly lower in the NDR group compared to the Control group, and were further lower in the DR group compared to the NDR group. Plasma carotenoid levels were significantly inversely associated with the duration of diabetes, RBS and HbA1c but positively associated with HDL. This study demonstrated decreased plasma levels and lower dietary intakes of carotenoids in DR subjects.

Physiological significance of link between polycyclic aromatic hydrocarbons and serum nutritional biomarkers.

It is well-known that exposure to polycyclic aromatic hydrocarbons (PAH) may cause adverse health impacts. However, there are few investigations assessing the association between PAH exposure and the nutritional status of the general population. Thus, the purpose of this investigation was to assess the correlation between PAH metabolites and nutritional biomarkers in the U.S. general population. From the 2003-2006 National Health and Nutrition Examination Survey, 4,545 eligible participants were included in this cross-sectional study. To assess PAH exposure, ten urinary PAH metabolites were measured. Eleven serum nutritional biomarkers including carotenoids and vitamins were measured. The association between PAH metabolites and serum nutritional biomarkers was investigated using multivariate linear regression models. Increased 2-hydroxyfluorene was inversely correlated with elven serum nutritional biomarkers: α-carotene (ß = -0.529, p < 0.001), ß-cryptoxanthin (ß = -0.968, p < 0.001), cis-ß carotene (ß = -0.149, p < 0.001), lutein and zeaxanthin (ß = -1.188, p < 0.001), retinyl palmitate (ß = -0.145, p < 0.001), retinyl stearate (ß = -0.025, p = 0.006), total lycopene (ß = -1.074, p < 0.001), trans-ß carotene (ß = -2.268, p < 0.001), trans-lycopene (ß = -0.466, p < 0.003), retinol (ß = -0.694, p = 0.004) and 25-hydroxyvitamin D (ß = -1.247, p = 0.007). Increased 3-hydroxyfluorene was inversely correlated with eleven serum nutritional biomarkers: α-carotene (ß = -0.740, p < 0.001), ß-cryptoxanthin (ß = -1.377, p < 0.001), cis-ß carotene (ß = -0.205, p < 0.001), lutein and zeaxanthin (ß = -1.521, p < 0.001), retinyl palmitate (ß = -0.209, p < 0.001), retinyl stearate (ß = -0.034, p = 0.014), total lycopene (ß = -1.20, p = 0.007), trans-ß carotene (ß = -3.185, p < 0.001), trans-lycopene (ß = -0.490, p = 0.039), retinol (ß = -1.366, p < 0.001) and 25-hydroxyvitamin D (ß = -2.483, p < 0.001). Increased 1-hydroxypyrene was inversely correlated with eight serum nutritional biomarkers: α-carotene (ß = -0.601, p = 0.001), ß-cryptoxanthin (ß = -1.071, p = 0.001), cis-ß carotene (ß = -0.170, p = 0.001), lutein and zeaxanthin (ß = -1.074, p < 0.001), retinyl palmitate (ß = -0.214, p = 0.005), retinyl stearate (ß = -0.041, p = 0.043), total lycopene (ß = -1.664, p = 0.011) and retinol (ß = -1.381, p = 0.011). These results demonstrate that PAH exposure is significantly correlated with decreased levels of serum nutritional biomarkers.

Reduced plasma carotenoids in individuals suffering from metabolic diseases with disturbances in lipid metabolism: a systematic review and meta-analysis of observational studies.

This review summarises the association between serum carotenoids, serum retinoids and dietary intake outcomes with obesity/overweight and individuals with metabolic diseases with disturbances in lipid metabolism. Observational studies reporting dietary intakes and serum concentrations of carotenoids and retinol were collected from Medline and Web of Science. Mean differences were calculated between "cases" (classified as obese, overweight or having a metabolic disease with disturbances in lipid metabolism; i.e. non-alcoholic fatty liver disease, type 2 diabetes, dyslipidaemia or metabolic syndrome) and "comparator group" (classified as normal weight healthy individuals) and summarised in meta-analyses. Significant summary measures were observed for most serum provitamin A and non-provitamin A carotenoids. Studies reporting total serum carotenoids had shown the greatest decrease (-0.28 µmol/l [-0.33, -0.23], p<.001, I2=62.5%, n = 7). There were no significant summary measures for dietary outcomes, suggesting a physiological role of low serum carotenoids in the development of obesity and associated diseases.

Plasma carotenoids and medial temporal lobe atrophy in older adults.

BACKGROUND & AIMS: Carotenoids are vegetable pigments with neuroprotective properties. Clinical studies found efficacy of specific carotenoids on improving brain perfusion and functioning with aging. However, evidence of an effect on neurodegeneration, which may require longer follow-up period to observe, is more limited. Leveraging biomarkers from a large population-based cohort study of older adults, we investigated whether blood carotenoids were associated with atrophy of the medial temporal lobe (a biomarker of neurodegeneration in aging) over 10 years. METHODS: This study included 461 dementia-free participants from the Three-City Bordeaux study (aged ≥65) who had plasma carotenoids measured at baseline and up to three repeated brain imaging exams in the subsequent 10 years. RESULTS: In adjusted linear mixed models, each increase of 1 SD in plasma level of total carotenoids and of ß-carotene was associated with 0.02 cm3 (95% CI, 0.001-0.04; P = 0.04) and 0.02 cm3 (95% CI, 0.01-0.04; P = 0.008) smaller medial temporal lobe volume loss per year, respectively. CONCLUSIONS: Our results based on a unique long-term prospective evaluation of a neuroimaging biomarker suggest a beneficial role of carotenoids for the prevention of age-related neurodegeneration.