Plasma Lutein Concentrations Research Articles

Study protocol for a 15-week randomised controlled trial assessing the independent effects of high-cholesterol and high-saturated fat diets on LDL cholesterol

IntroductionPrevious research has associated high dietary cholesterol intake with raised low-density lipoprotein cholesterol (LDL-C) and thus increased risk for cardiovascular disease (CVD). Emerging research suggests that it is saturated fat,...

Associations between dietary intake and glucose tolerance in clinical and metabolomics-based metabotypes

BackgroundMetabotyping is a novel concept to group metabolically similar individuals. Different metabotypes may respond differently to dietary interventions; hence, metabotyping may become an important future tool in precision nutrition strategies. However, it is not known if metabotyping based on comprehensive omic data provides more useful identification of metabotypes compared to metabotyping based on only a few clinically relevant metabolites.AimThis study aimed to investigate if associations between habitual dietary intake and glucose tolerance depend on metabotypes identified from standard clinical variables or comprehensive nuclear magnetic resonance (NMR) metabolomics.MethodsWe used cross-sectional data from participants recruited through advertisements aimed at people at risk of type 2 diabetes mellitus (n = 203). Glucose tolerance was assessed with a 2-h oral glucose tolerance test (OGTT), and habitual dietary intake was recorded with a food frequency questionnaire. Lipoprotein subclasses and various metabolites were quantified with NMR spectroscopy, and plasma carotenoids were quantified using high-performance liquid chromatography. We divided participants into favorable and unfavorable clinical metabotypes based on established cutoffs for HbA1c and fasting and 2-h OGTT glucose. Favorable and unfavorable NMR metabotypes were created using k-means clustering of NMR metabolites.ResultsWhile the clinical metabotypes were separated by glycemic variables, the NMR metabotypes were mainly separated by variables related to lipoproteins. A high intake of vegetables was associated with a better glucose tolerance in the unfavorable, but not the favorable clinical metabotype (interaction, p = 0.01). This interaction was confirmed using plasma concentrations of lutein and zeaxanthin, objective biomarkers of vegetable intake. Although non-significantly, the association between glucose tolerance and fiber intake depended on the clinical metabotypes, while the association between glucose tolerance and intake of saturated fatty acids and dietary fat sources depended on the NMR metabotypes.ConclusionMetabotyping may be a useful tool to tailor dietary interventions that will benefit specific groups of individuals. The variables that are used to create metabotypes will affect the association between dietary intake and disease risk.

Impacts of regular consumption of grapes on macular pigment accumulation in Singapore older adults: a randomized controlled trial.

Background: Oxidative stress is a key risk factor for visual impairment and consuming dietary antioxidant-rich foods may help in managing visual impairments. However, a limited number of studies have investigated the effect of dietary antioxidant-rich food including grapes on eye health in older adults. Objectives: To assess the effects on macular pigment accumulation of regular consumption of grapes in Singapore older adults. Methods: This was a 16 week, double-blind, randomized, placebo-controlled trial. Thirty-four Singapore older adults were randomized into regularly consuming either 46 g day-1 of freeze-dried table grape powder (the intervention group) or the same amount of placebo powder (the control group). Macular pigment optical density (MPOD), skin carotenoid status, advanced glycation end product (AGEs) status and dietary lutein intake were assessed every 4 weeks, and plasma lutein concentration, total antioxidant capacity and total phenolic content were measured every 8 weeks. Results: A significant time effect (p = 0.007) was observed for MPOD, and this is largely attributed to the improvement in the MPOD for the intervention group, as a significant increase was observed only in this group (week 0: 0.56 ± 0.04 D.U.; week 16: 0.61 ± 0.04 D.U., p < 0.01). Additionally, a significant increase in plasma total antioxidant capacity (week 0: 0.26 ± 0.13 mM TEAC; week 16: 0.36 ± 0.20 mM TEAC, p < 0.01) and total phenolic content (week 0: 10.50 ± 0.44 mg L-1 GAE; week 16: 12.58 ± 0.55 mg L-1 GAE, p < 0.001) was observed for the intervention group only. In contrast, a significant increase in skin AGE status was observed in the control group (week 0: 2.47 ± 0.24; week 16: 2.99 ± 0.12, p < 0.05) while this was mitigated in the intervention group. There were no differences in dietary lutein intake, plasma lutein concentration and skin carotenoid status between groups throughout the study. Conclusions: Regular intake of grapes may improve eye health in Singapore older adults, specifically in augmenting MPOD, which can be explained by an increase in plasma total antioxidant capacity and phenolic content, and the downregulation of AGEs. This study was registered at clinicatrials.gov as NCT05064865.

Plasma Micronutrient Profile of Prostate Cancer Cases Is Altered Relative to Healthy Controls-Results of a Pilot Study in South Australia.

Emerging evidence suggests possible roles of micronutrients in cancer prevention. The study was designed to test the hypothesis that the concentration profile of plasma micronutrients (i.e., the nutriome) in prostate cancer patients is different from that of healthy controls. Plasma samples from 116 Caucasian men diagnosed with late onset of prostate cancer and 132 matched controls from the South Australian population were collected and analysed for their concentration of micronutrients. Plasma concentrations of lutein, lycopene, α-carotene and β-carotene were found to be significantly lower in prostate cancer patients (p = 0.03, 0.008, 0.002 and 0.002, respectively). Plasma levels of elements such as iron, copper, calcium and sulphur were significantly higher (p &lt; 0.0001, &lt;0.0001, &lt;0.0001 and p = 0.0003, respectively) while that of selenium was significantly lower (p = 0.002) in prostate cancer patients. Higher prostate cancer risk is significantly associated with plasma levels below the median of lycopene (OR: 2.24), α-carotene (OR: 2.13), β-carotene (OR: 1.97) and high levels above the median of iron (OR: 2.31), calcium (OR: 4.35) and sulphur (OR: 2.39). The results of this study suggest that the plasma nutriome could be a useful diagnostic of prostate cancer risk.

Plasma lutein and zeaxanthin concentrations associated with musculoskeletal health and incident frailty in The Irish Longitudinal Study on Ageing (TILDA)

IntroductionLutein and zeaxanthin are diet-derived carotenoids that are proposed to help mitigate frailty risk and age-related declines in musculoskeletal health via their anti-oxidant and anti-inflammatory properties. Therefore, this study aimed to investigate the association between lutein and zeaxanthin status and indices of musculoskeletal health and incident frailty among community-dwelling adults aged ≥50 years in the Irish Longitudinal Study on Ageing (TILDA). MethodsCross-sectional analyses (n = 4513) of plasma lutein and zeaxanthin concentrations and grip strength, usual gait speed, timed up-and-go (TUG), probable sarcopenia (defined as grip strength <27 kg in men, <16 kg in women), and bone mass (assessed using calcaneal broadband ultrasound stiffness index) were performed at Wave 1 (2009–2011; baseline). In the longitudinal analyses (n = 1425–3100), changes in usual gait speed (at Wave 3, 2014–2015), grip strength (Wave 4, 2016) and TUG (at Wave 5, 2018), incident probable sarcopenia (at Wave 4) and incident frailty (Fried's phenotype, Frailty Index, FRAIL Scale, Clinical Frailty Scale-classification tree, at Wave 5) were determined. Data were analysed using linear and ordinal logistic regression, adjusted for confounders. ResultsCross-sectionally, plasma lutein and zeaxanthin concentrations were positively associated with usual gait speed (B [95 % CI] per 100-nmol/L higher concentration: Lutein 0.59 [0.18, 1.00], Zeaxanthin 1.46 [0.37, 2.55] cm/s) and inversely associated with TUG time (Lutein −0.07 [−0.11, −0.03], Zeaxanthin −0.14 [−0.25, −0.04] s; all p < 0.01), but not with grip strength or probable sarcopenia (p > 0.05). Plasma lutein concentration was positively associated with bone stiffness index (0.54 [0.15, 0.93], p < 0.01). Longitudinally, among participants who were non-frail at Wave 1, higher plasma lutein and zeaxanthin concentrations were associated lower odds of progressing to a higher frailty category (e.g. prefrailty or frailty) by Wave 5 (ORs 0.57–0.89, p < 0.05) based on the Fried's phenotype, FRAIL Scale and the Clinical Frailty Scale, and in the case of zeaxanthin, Frailty Index. Neither plasma lutein nor zeaxanthin concentrations were associated with changes in musculoskeletal indices or incident probable sarcopenia (p > 0.05). ConclusionHigher plasma lutein and zeaxanthin concentrations at baseline were associated with a reduced likelihood of incident frailty after ~8 years of follow up. Baseline plasma lutein and zeaxanthin concentrations were also positively associated with several indices of musculoskeletal health cross-sectionally but were not predictive of longitudinal changes in these outcomes over 4–8 years.

Dose-Response Relationship Between Oral Lutein Intake and Plasma Lutein Concentration: A Randomized Controlled Trial.

Lutein was shown to provide health benefits for a few diseases. The dose-response relation of oral lutein intake in humans has rarely been reported. The objective is to investigate the dose-response relation between oral lutein intake and plasma lutein concentration in humans. Forty subjects were recruited from Qingdao University, China in 2014. The subjects were randomly divided into four groups: (1–3) consuming 10, 20, or 40 mg lutein by one, two, or four capsules of lutein A, respectively; (4) consuming 20 mg lutein by two capsules of lutein B (containing 280 mg n-3 fatty acid). After a single oral dose, plasma lutein concentrations were measured at 9-time points. The raise of plasma lutein concentration by a 40 mg dose was significantly higher than by a 10 or 20 mg dose. Plasma lutein concentrations were not significantly different between taking 20 mg lutein A and 20 mg lutein B. A dose-response relation was demonstrated between oral lutein administration and plasma lutein concentration. The dose-response relation was more pronounced among men. The current work provides a scientific basis for recommending a dietary intake level of lutein. Future work should validate the results in other ethnic and age groups.

Plasma Choline Concentration Is Positively Correlated with Visual Acuity in 18-Month Old Toddlers: Preliminary Findings

Abstract Objectives Adequate dietary intake of key nutrients is critical for brain and eye development in the first 1000 days of life. In particular, docosahexaenoic acid (DHA) and lutein are known for their roles in the development of visual acuity during infancy and early childhood. Preliminary data suggest that choline may also play a role in visual acuity; however, little is known about choline's role in visual acuity during toddlerhood. We hypothesize thatbiomarkers for DHA, choline, and lutein status are positively correlated with visual acuity in toddler-aged children. Methods We studied cross-sectional baseline data from participants aged 18 months ± 2 weeks enrolled in a partially randomized controlled trial investigating associations between feeding patterns, nutrient biomarker status, and neurodevelopmental outcomes. Participants were recruited in Metro Vancouver, Canada. Visual acuity was measured using the Cardiff Acuity test with the logarithm of the minimum angle of resolution (LogMAR) as the measure of visual acuity. The child's confidence in test completion was rated using a 5-point Likert scale; test results with confidence scores below 3 were excluded from further analyses. Results Sixty-nine toddlers, with preliminary data available at the time of analysis, had an equal distribution of males and females, 68% were the first-born child, and 55%, 19%, and 26% were of European, Chinese or other ethnicity, respectively. Preliminary (unadjusted) findings showed a positive correlation between plasma choline and visual acuity (rho = 0.33, P &amp;lt; 0.05). No significant correlations were observed between visual acuity and DHA concentration (as a percentage of total fatty acids from red blood cells) nor between visual acuity and plasma lutein concentration. Conclusions Plasma choline may be positively associated with visual acuity at 18 months of age. These preliminary findings require confirmation in a larger sample size and testing of the causality of this relationship in a dose-dependency trial. Acknowledgment: We are grateful for Dr. Margaret Woodhouse's guidance in the methodology of the Cardiff Acuity test. Funding Sources This study is supported by The University of British Columbia, and the British Columbia Children's Hospital Research Institute and is funded by Société des Produits Nestlé S.A.

Nutritional Status in Breastfed 18-Month Old Toddlers: Cross-Sectional Findings

Abstract Objectives Adequate nutrition is critical for infant and toddler growth and development. Breastfeeding is recommended until 2 years of age or beyond, and breastmilk is an important source of energy and nutrients for many toddlers beyond 12 mo of age. The composition of breastmilk changes over time during the lactation period. It is not yet known how prolonged breastfeeding influences nutritional status in toddlers aged 12–24 mo. The objective of this research was to explore biomarker differences between breastfed and non-breastfed toddlers residing in Metro Vancouver, Canada. Methods We studied cross-sectional baseline data from 18 mo old toddlers enrolled in a partially randomized controlled trial. Toddlers were categorized as breastfed (currently receiving breastmilk as the primary milk source, i.e., ≥2 times/day) and non-/occasionally-breastfed. Results Sixty-five toddlers, with preliminary data available at the time of analysis, had an equal distribution of males and females, 68% were the first-born child, and 55%, 19%, and 26% were of European, Chinese or other ethnicity, respectively. Twenty-eight of the 18-mo old toddlers (43%) were still breastfed, with 93% (n = 26) receiving breastmilk as the primary source of milk. Plasma vitamin A was lower, and plasma betaine and docosahexaenoic acid (DHA) as a percentage of red blood cell fatty acids were significantly higher in breastfed toddlers compared to the other group (all P &amp;lt; 0.05; Mann-Whitney U test). There was a trend for lower plasma ferritin in breastfed toddlers (P &amp;lt; 0.1). Plasma lutein, vitamin D, and choline concentrations did not differ between groups. Conclusions These preliminary findings reflect possible differences in biomarker status between breastfed and non-/occasionally-breastfed toddlers. The analysis of total dietary intake and complementary feeding patterns is warranted to determine what types of food and beverages take the place of breastmilk in 18 mo old toddlers, and which dietary sources may explain the differing nutrient status. Funding Sources This study is supported by The University of British Columbia, and the British Columbia Children's Hospital Research Institute, Canada, and is funded by Société des Produits Nestlé S.A.

Effects of Lutein Supplementation in Japanese Patients with Unilateral Age-Related Macular Degeneration: The Sakai Lutein Study

This prospective randomized double-masked study investigated the effects of 20 mg lutein supplementation with two different capsules (beeswax or glycerol fatty acid esters) for 6 months on the fellow eyes of 39 Japanese patients with unilateral age-related macular degeneration, and assessed the factors associated with baseline plasma lutein concentration via lifestyle interviews. Macular pigment optical density (MPOD), determined with the two-wavelength autofluorescence method, increased over time in the beeswax group (ANOVA, p = 0.0451), although the increase from 3 months to 6 months was only marginally significant. No significant increase was observed in the glycerol fatty acid esters group (ANOVA, p = 0.7396). Plasma lutein concentrations significantly increased at 3 and 6 months from baseline in both groups (both p < 0.01). In a multiple regression model, age was negatively associated with higher plasma lutein concentration (p = 0.0305), while consumption of green vegetables was positively associated with baseline plasma lutein concentration (p = 0.0322). In conclusion, a significant increase in MPOD was not fully confirmed with 6 months intake duration despite a significant increase in plasma lutein concentrations. Consumption of green vegetable was confirmed to be associated with plasma lutein concentration after adjusting for other potential factors including age.

A Moderate-Fat Diet with One Avocado per Day Increases Plasma Antioxidants and Decreases the Oxidation of Small, Dense LDL in Adults with Overweight and Obesity: A Randomized Controlled Trial

Background:Avocados are a nutrient-dense source of MUFAs and are rich in antioxidants. Avocados have an additional LDL cholesterol (LDL-C) lowering effect beyond that observed when their MUFAs are substituted for SFAs, especially on small, dense LDL (sdLDL) particles, which are susceptible to in vivo oxidation and associated with increased risk of cardiovascular disease (CVD). Objectives:We investigated whether a healthy diet with 1 avocado daily decreased the following secondary outcomes: circulating oxidized LDL (oxLDL) and related oxidative stress markers. Methods:A randomized, crossover, controlled feeding trial was conducted with 45 men and women, aged 21–70 y, with overweight or obesity and elevated LDL-C (25th–90th percentile). Three cholesterol-lowering diets were provided (5 wk each) in random sequences: a lower-fat (LF) diet (24% calories from fat—7% SFAs, 11% MUFAs, 6% PUFAs) and 2 moderate-fat (MF) diets (34% calories from fat—6% SFAs, 17% MUFAs, 9% PUFAs): the avocado (AV) diet included 1 Hass avocado (~136 g) per day, and the MF diet used high oleic acid oils to match the fatty acid profile of 1 avocado. A general linear mixed model was used to analyze the treatment effects. Results:Compared with baseline, the AV diet significantly decreased circulating oxLDL (—7.0 U/L, –8.8%, P = 0.0004)and increased plasma lutein concentration (19.6 nmol/L, 68.7%, P < 0.0001), and both changes differed significantlyfrom that after the MF and LF diets (P ≤ 0.05). The change in oxLDL caused by the AV diet was significantly correlatedwith the changes in the number of sdLDL particles (r = 0.32, P = 0.0002) but not large, buoyant LDL particles. Conclusions:One avocado a day in a heart-healthy diet decreased oxLDL in adults with overweight and obesity, and the effect was associated with the reduction in sdLDL. This trial was registered at http://www.clinicaltrials.gov as NCT01235832.

Study of Formulation Development Based on the Pharmacokinetic Properties of Functional Food Components

Preventive medicine and anti-aging medicine have received much attention recently due to an increase in the proportion of elderly people in the population, and to an increase in patients with lifestyle diseases. Oxidative stress is involved in the onset of lifestyle diseases, and various antioxidant supplements and antioxidant-fortified functional foods have recently become available. Many epidemiological studies have shown relationships between the consumption of polyphenol and carotenoid-rich foods and the prevention of lifestyle diseases. We have focused on the absorption mechanism of these food components that show low bioavailability, and have made efforts to improve their poor absorption based on their pharmacokinetic properties. In this report, as examples, we describe the enhancement of the absorption of coenzyme Q10 (CoQ10) and lutein. To improve the absorption of CoQ10, we focused on the component of emulsion. We found that a higher plasma concentration of CoQ10 could be obtained by creating an emulsion containing a surfactant with a higher hydrophile-lipophile balance (HLB) value. For the improvement of lutein absorption, we prepared a solid dispersion and self-emulsifying drug delivery system. It was shown that the plasma concentrations of lutein in these two formulation groups were increased compared with that in the powder group. The absorption of lutein was also evaluated by its cumulative amount in the lymph system. Our data showed that lutein is transferred from the small intestine into the lymph stream, rather than into the blood stream. Further investigations to improve the absorption of these components are in progress.

Milk and Plasma Lutein and Zeaxanthin Concentrations in Chinese Breast-Feeding Mother–Infant Dyads With Healthy Maternal Fruit and Vegetable Intake*

Objectives: While others have reported that milk from coastal Chinese women contains high levels of lutein and zeaxanthin, no research has determined the corresponding infant plasma response. Whether infant plasma levels increase commensurately provides important guidance for supplementation of these increasingly intriguing carotenoids in breast-feeding mothers and formula-fed infants.Methods: Fifty-six mother–infant pairs with a maternal diet rich in eggs, green leafy vegetables, and fruit were enrolled between 6 and 16 weeks of lactation. Milk samples and blood samples from both the mother and infant were collected at entry. Maternal 3-day dietary records and a second milk sample were collected 1 to 3 weeks later.Results: Mean milk lutein concentrations in samples 1 and 2 were 6.5 and 7.7 μg/dL (range 1–22.5 μg/dL), and for zeaxanthin, 1.6 and 1.7 μg/dL (range 1–5.9 μg/dL). Lutein concentrations in infant plasma (18.2 μg/dL) were similar to those in maternal plasma (21.6 μg/dL); zeaxanthin was lower than lutein in both maternal (3.1 μg/dL) and infant (2.9 μg/dL) plasma. Infant and maternal mean plasma lutein and zeaxanthin concentrations were higher than those in both milk samples 1 and 2 (lutein, 6.9 and 8.2 μg/dL; zeaxanthin, 1.9 and 2.0 μg/dL). Infant plasma lutein and zeaxanthin concentrations positively correlated with those in milk sample 1 (lutein, r2 = 0.15, p = 0.004; zeaxanthin, r2 = 0.21, p < 0.001).Conclusions: Together, these results reveal that high milk concentrations of lutein and zeaxanthin driven by healthy maternal intakes of xanthophyll rich foods are associated with high infant plasma concentrations. These findings will be useful for determining appropriate lutein fortification strategies.Clinical Study.gov registration number: NCT01669655.

Plasma Concentrations of Lutein and Zeaxanthin, Macular Pigment Optical Density, and Their Associations With Cognitive Performances Among Older Adults

We investigated the cross-sectional associations between macular pigment optical density (MPOD), plasma lutein (L), and zeaxanthin (Z) concentrations and cognitive function in 184 older adults of the 3-City-Bordeaux cohort. MPOD was measured using the two-wavelength autofluorescence method with a modified scanning laser ophthalmoscope. Plasma L and Z (L+Z) concentrations were determined by high-performance liquid chromatography and were considered either crude or expressed as a ratio of the concentration of plasma lipids (total cholesterol [TC] + triglycerides [TG]). Cognitive performances were assessed using the following four separate neuropsychological tests: the Mini-Mental State Examination (MMSE), the Isaacs Set Test (IST), the Benton Visual Retention Test (BVRT), and the sum of the three free recalls of the Free and Cued Selective Reminding Test (FCSRT). These test results were summarized by a composite global cognitive z-score. Higher MPOD at 0.5° was significantly associated with a higher composite z-score (β = 0.15, 95% confidence interval [CI] 0.04-0.26), higher BVRT (β = 0.39, 95%CI 0.08-0.70), and higher IST (β = 1.16, 95%CI 0.11-2.22) performances. Higher plasma L+Z concentrations were significantly associated with higher IST scores (β = 0.97, 95%CI 0.01-1.94). Furthermore, a higher L+Z/TC+TG ratio was associated with a higher composite z-score (β = 0.12, 95%CI 0.01-0.23), along with higher IST (β = 1.02, 95%CI 0.002-2.04) and FCSRT (β = 1.55, 95%CI 0.41-2.69) performances. This analysis suggested that both higher MPOD and L+Z concentrations were significantly associated with higher cognitive performances. However, MPOD measurements have the advantage of being a fast and representative measure of long-term carotenoid intake.

Enhancement of lymphatic transport of lutein by oral administration of a solid dispersion and a self-microemulsifying drug delivery system

Lutein is located in the macula lutea in the human eye. Since humans cannot synthesize lutein de novo, it must be digested as food. Some studies including our previous study showed very low absorption of lutein after oral administration. These studies also suggested that the absorption route of lutein from the small intestine involves not only the blood but also the lymph. The aim of this study was to clarify the transfer of lutein into lymph and the tissue distribution after oral administration of a solid dispersion (SD) and a self-microemulsifying drug delivery system (SMEDDS) for improvement of the absorption. We used thoracic lymph-cannulated rats. It was shown that the plasma concentrations of lutein in the SD and SMEDDS groups were increased compared with that in the powder group. The absorption of lutein after oral administration of each formulation was clearly evaluated by its cumulative amount in lymph. Our data clearly showed that lutein is transferred into the lymph stream from the small intestine.

The Relationship Between Plasma Concentrations of Lutein and Zeaxanthin with Self-Reported and Actual Prevalence of AMD in an Irish Population-Based Sample

ABSTRACTPurpose: To investigate plasma lutein (L) and zeaxanthin (Z) concentrations with grading-confirmed and self-reported prevalence of age-related macular degeneration (AMD).Material and methods: Data collected from a nationally representative prospective cohort study of community-dwelling adults aged 50 years and over in the Republic of Ireland. Participants underwent a computer-assisted personal interview and a center-based health assessment. Plasma concentrations of L and total Z (Z and meso-zeaxanthin [MZ]) were measured by high performance liquid chromatography, and retinal photographs were graded using a version of the AMD International Classification and Grading System. Consumption of supplements containing L and/or Z and/or MZ was recorded as supplement use. Four groups were identified: Group 1 (n = 24): AMD-afflicted and correctly aware; Group 2 (n = 264): AMD-afflicted but unaware; Group 3 (n = 41): AMD-free and incorrectly believed that they were afflicted with the condition; Group 4 (n = 4094): AMD-free and correctly self-reported absence of AMD.Results: Of 4,423 participants with plasma concentrations of L and Z and gradable retinal photographs, 288 (6.5%) were afflicted with AMD, and 65 (1.5%) self-reported AMD. Controlling for family history and age, the relationship between grading-confirmed AMD and plasma L was positive and significant (p < 0.001). Mean plasma concentrations of L in Group 2 (mean = 0.2162 ± 0.132 µmol) and Group 4 (mean = 0.2040 ± 0.121 µmol/L) were significantly lower than Group 1 (mean = 0.4691 ± 0.0.372 µmol/L) and Group 3 (mean = 0.3176 ± 0.0.235 µmol/L). Supplement use was reported by 41.7% and 17.1% of participants in Groups 1 and 3, respectively, but only 2.7% and 1.9% of participants in Groups 2 and 4, respectively.Conclusion: A belief that one suffers from AMD, whether justified or not, is associated with supplement use and with higher plasma concentrations of L.

Consumption of 2 eggs per day as compared to an oatmeal breakfast increases plasma carotenoids and markers associated with reverse cholesterol transport in young, healthy individuals

Despite the fact that the Dietary Guidelines for Americans 2015–2020 withdrew the previous restriction on dietary cholesterol (300 mg/day), consumption outside of this range is met with resistance from the public. Eggs are a primary source of cholesterol in the diet, and are a good source of high quality protein, vitamins, minerals, and antioxidant carotenoids. Therefore, we investigated the effects of two different isocaloric breakfasts, either two eggs/day or one bowl of oatmeal/day, on lipid metabolism and HDL functionality to compare the impact of regular consumption of these two foods. In the randomized, cross‐over intervention, participants included 26 women and 24 men, aged 18–30 y, with a BMI of 23.3 ± 3.2 kg/m2, and normolipidemic profile. Blood was collected at the end of each period to assess apolipoproteins and carotenoid concentrations, and paraoxonase‐1 (PON1), lecithin cholesterol acyltransferase (LCAT) and cholesteryl ester transfer protein (CETP) activities. Our initial findings reported no increase in LDL/HDL ratio, as both LDL‐C and HDL‐C increased, while there were no significant increases in plasma triglycerides, glucose or liver enzymes following consumption of 2 eggs for breakfast every day for four weeks. However, we sought to further examine the effects of regular egg consumption on markers of HDL metabolism and HDL functionality. Apolipoproteins were assessed using a magnetic bead‐based multiplex assay. While there was no difference in apolipoproteins A‐II, B, C‐II, C‐III, or E between groups, apoA‐I was significantly increased following egg consumption (p &lt; 0.05). ApoA‐I is the primary apolipoprotein associated with reverse cholesterol transport (RCT), the transfer of excess cholesterol from extrahepatic tissues to HDL for clearance. Plasma lutein and zeaxanthin concentrations were increased following egg consumption (p &lt; 0.001), which suggests increased presence of antioxidants in circulation. There was no difference in PON1 activity or CETP activity between groups. Additionally, LCAT, the enzyme responsible for converting free cholesterol into cholesteryl esters in HDL, was significantly increased following consumption of eggs as compared to an oatmeal breakfast (p &lt; 0.05). These findings demonstrate that, compared to oatmeal, regular egg consumption (2/day) at breakfast may result in improvements in markers of HDL functionality in healthy populations.Support or Funding InformationFunding: award to MLF by the Esperance Family Foundation and Egg Nutrition Center Dissertation Fellowship awarded to ACM.

Superior Oral Bioavailability in Beagle Dogs of Lutein Derived from a Novel Manufacturing Process

ObjectiveLutein, an essential micronutrient that plays a critical role in promoting immune health, is being developed commercially (as Lutea® 20) using a novel manufacturing process. Lutea® 20 features reduced lutein crystal size (&gt;99%&lt;0.5 microns) compared to an existing lutein‐containing product, Existing Lutein Product (ELP) (64%&lt;0.5 microns), along with enhanced stability without the requirement for including protective antioxidants. The objective of this study was to compare the oral bioavailability of lutein derived from Lutea® 20 (manufactured using novel technology) to that of lutein derived from ELP (manufactured using traditional technology).MethodsThe study was performed in 12 healthy Beagle dogs [pre‐study mean body weight (bw) of 14.3 ± 2.6 kg)] using a cross‐over, 4 × 4 Latin square design. Each animal was randomly assigned to one sequence group, and 1 of 4 treatments administered by oral gavage during each period, i.e., Lutea® 20 at 2.5 and 5 mg/kg bw and ELP at 2.5 and 5 mg/kg bw. All animals received all the treatments in sequence, with a between‐period wash‐out of 13–15 days. For each period, blood samples were collected from each animal at −24 h (pre‐administration sample), and at 2 h, 4 h, 6 h, 9 h, 12 h, 18 h, 24 h, 36 h, and 48 h post‐dosing. Lutein concentration in plasma was determined using a novel, sensitive (theoretical limit of detection = 315 pg/ml; lower limit of quantitation = 2.5 ng/ml; upper limit of quantitation = 125 ng/ml), and precise [interday % coefficients of variation: 2.7% (2.5 ng/ml), 5.2% (12.5 ng/ml), 7.2% (125 ng/ml)] high performance liquid chromatographic method with ultraviolet‐visible detection, validated as specified by the European Agency for the Evaluation of Medicinal Products and the European Medicines Agency. Maximum plasma concentration (Cmax) and the area under the curve (AUC)0–48h were calculated for each animal in each period. Data were analyzed by analysis of variance followed Tukey's‐b post‐hoc test to determine differences in the Cmax and AUC0–48h among groups.ResultsFor both doses of each formulation, maximum plasma lutein concentrations occurred at 4–6 h and gradually returned to baseline by 24 h. For each dose, the Cmax (89, 112, 60, 79 ng/ml for 2.5 and 5 mg/kg Lutea, 2.5 and 5 mg/kg ELP, respectively) and the AUC0–48h (1390, 1874, 986, 1324 ng • h/ml for 2.5 and 5 mg/kg Lutea® 20, 2.5 and 5 mg/kg ELP, respectively) for lutein were approximately 40–50% greater in the Lutea® 20 formulation compared to the existing formulation (P &lt; 0.05, Lutea® 20 vs ELP, for each parameter at each dose).ConclusionLutein (Lutea® 20), produced using a novel manufacturing technology, possesses superior oral bioavailability compared to an existing lutein‐containing product (ELP), and this observed superiority was likely due to the smaller crystal size of lutein in Lutea® 20 compared to lutein in ELP.Support or Funding InformationNovus International, St. Charles, MO USA

Association Between Myopia, Ultraviolet B Radiation Exposure, Serum Vitamin D Concentrations, and Genetic Polymorphisms in Vitamin D Metabolic Pathways in a Multicountry European Study

Myopia is becoming increasingly common globally and is associated with potentially sight-threatening complications. Spending time outdoors is protective, but the mechanism underlying this association is poorly understood. To examine the association of myopia with ultraviolet B radiation (UVB; directly associated with time outdoors and sunlight exposure), serum vitamin D concentrations, and vitamin D pathway genetic variants, adjusting for years in education. A cross-sectional, population-based random sample of participants 65 years and older was chosen from 6 study centers from the European Eye Study between November 6, 2000, to November 15, 2002. Of 4187 participants, 4166 attended an eye examination including refraction, gave a blood sample, and were interviewed by trained fieldworkers using a structured questionnaire. Myopia was defined as a mean spherical equivalent of -0.75 diopters or less. Exclusion criteria included aphakia, pseudophakia, late age-related macular degeneration, and vision impairment due to cataract, resulting in 371 participants with myopia and 2797 without. Exposure to UVB estimated by combining meteorological and questionnaire data at different ages, single-nucleotide polymorphisms in vitamin D metabolic pathway genes, serum vitamin D3 concentrations, and years of education. Odds ratios (ORs) of UVB, serum vitamin D3 concentrations, vitamin D single-nucleotide polymorphisms, and myopia estimated from logistic regression. Of the included 3168 participants, the mean (SD) age was 72.4 (5) years, and 1456 (46.0%) were male. An SD increase in UVB exposure at age 14 to 19 years (OR, 0.81; 95% CI, 0.71-0.92) and 20 to 39 years (OR, 0.7; 95% CI, 0.62-0.93) was associated with a reduced adjusted OR of myopia; those in the highest tertile of years of education had twice the OR of myopia (OR, 2.08; 95% CI, 1.41-3.06). No independent associations between myopia and serum vitamin D3 concentrations nor variants in genes associated with vitamin D metabolism were found. An unexpected finding was that the highest quintile of plasma lutein concentrations was associated with a reduced OR of myopia (OR, 0.57; 95% CI, 0.46-0.72). Increased UVB exposure was associated with reduced myopia, particularly in adolescence and young adulthood. The association was not altered by adjusting for education. We found no convincing evidence for a direct role of vitamin D in myopia risk. The relationship between high plasma lutein concentrations and a lower risk of myopia requires replication.

Lutein and atherosclerosis: Belfast versus Toulouse revisited

In 1995 we reported that mean plasma lutein concentrations in salaried men and women from Toulouse in Southern France were double those in subjects recruited from general practitioner lists in Belfast, Northern Ireland. At the time incidence of coronary heart disease (CHD) in Southern France was among the lowest in Europe and was much higher in Northern Ireland. Plasma lutein is a biomarker of vegetable and fruit intake and evidence suggests that high concentrations are generally associated with better cardiometabolic health. At the time we speculated like others that role of the carotenoids may well have been to prevent oxidation of lipid in the lipoproteins and so reduce the uptake of oxidised lipid by macrophages and its deposition within the intimal layers of the major arteries as plaque.It is now widely accepted that CHD is an inflammatory disease and that macrophages within plaque together with tissue damage contribute to this inflammation. Stimulated macrophages release cytokines to activate the immune system both locally and systemically. Precursor complement proteins in the blood are activated to assist immune cells in phagocytosis and cell repair. Individuals with a history of arteriosclerosis display significantly higher concentrations of complement factors C3 and C3a than subjects without such a history. Metabolism of C3 via the alternate complement pathway can give rise to the membrane attack complex (MAC) which creates a hole or pore in pathogens or host cells, killing the cell. Recent studies in patients with early age related macular disease (AMD) who also exhibit similar elevated concentrations of complement proteins in their blood, showed supplementation with lutein progressively decreased the amount of the MAC and other complement factors in the blood. Lutein was used in the supplementation experiments because it is an important constituent of macular pigment. Thus the healthier cardiometabolic features displayed by the people in Toulouse may have been due to the effects of concurrent high concentrations of plasma lutein on the immune system and complement in particular. Other carotenoids may exert similar antioxidant effects but we and others found no differences in antioxidant nutrients between subjects in Toulouse and Belfast or between subjects with asymptomatic markers of atherosclerosis and controls.

Non-Dietary Correlates and Determinants of Plasma Lutein and Zeaxanthin Concentrations in the Irish Population.

To investigate non-dietary correlates and determinants of plasma lutein (L) and zeaxanthin (Z) concentrations in The Irish Longitudinal Study on Ageing (TILDA) sample. Cross-sectional study. Community dwelling adults in the Republic of Ireland (ROI). 3,681 participants aged 50 years and older. TILDA is a nationally representative prospective cohort study of community dwelling adults aged 50 years and over in the ROI. Demographic and health variables were collected during a face-to-face interview carried out in the home (n=8175), and a substantial proportion of these (n=5035; 62%) also attended a study visit in a health assessment centre. Blood samples collected at baseline (wave 1, the subject of the current study), were analysed for plasma concentrations of L and Z by reversed-phase high performance liquid chromatography, and macular pigment (MP) optical density was also measured (using customized heterochromatic flicker photometry). After excluding participants with eye disease, data from 3,681 participants were available for analysis. For this group of participants, plasma L and Z were inversely and significantly associated with body mass index (BMI), and were positively and significantly associated with MP, total cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) (p<0.001, for all). Plasma L and Z were significantly lower in males, current smokers, participants reporting less physical exercise, and participants reporting lower levels of education (p<0.05, for all). Plasma L was significantly higher in participants reporting a family history of age-related macular degeneration (AMD) (p=0.001), and in the group of ≥75 years old (p<0.05). For each of these variables, the significant associations remained after controlling for other potential confounding variables. The findings of this large study indicate that plasma concentrations of L and Z were lower in association with indicators of a poor lifestyle (high BMI, tobacco use, and less physical exercise) and in association with lower education, indicating that modifying lifestyle in a positive way is likely to be reflected in higher concentrations of plasma carotenoids, with consequential and putative health benefits.