Evidence of a role for fat-free body mass in modulation of plasma carotenoid concentrations in older men: studies with hydrodensitometry

Serum carotenoid interactions in premenopausal women reveal α-carotene is negatively impacted by body fat

Increasing body mass indices (BMIs) across the globe reflect pandemic shifts towards habitual positive energy imbalances. Excess body fat in individuals is often associated with high-energy and high-fat diets scanty in fresh produce. Carotenoids are fat-soluble pigments plentiful in many fruits and vegetables. They are well-known for provitamin A and antioxidant functions, but little research has been done related to carotenoid-body mass interactions. Serum carotenoids were analyzed relative to body fat to determine correlations between major serum carotenoids, retinol, BMI, fat mass, and lean mass. Healthy women ( n = 76), 19-50 years old, were categorized into two comparison groups determined by percent body fat measured by air displacement plethysomography (BOD POD®), i.e. <31% and ≥31% fat mass. Anthropometric and three-day diet records were completed for BMI and nutrient intake calculations, respectively. Serum α-carotene concentrations were strongly inversely associated with all measures of body composition ( P < 0.001 α-carotene) controlling for dietary intake and age, while β-carotene, lutein, and lycopene were not ( P > 0.05). Dietary intake between groups did not differ, including carrot consumption (a high dietary source of α-carotene). These results confirm previous carotenoid-health research and propose the need for further investigation of potential protective roles that α-carotene may perform for optimal health. Serum α-carotene may provide a deeper and clinically relevant purpose, beyond previous suggestions for its use as a biomarker for fruit and vegetable consumption, in that α-carotene may be a biomarker for chronic disease risk frequently linked with obesity. Impact statement Carotenoids are important pigments in fruit and vegetables and found in human serum. This study isolated a negative relationship between serum α-carotene and body fatness. As humans begin to live over a century, determining biomarkers of ultimate health is important. α-Carotene does not have the same distribution in the food supply as β-carotene and therefore is often overlooked in surveys. In part, this is due to the fact that β-carotene provides two molecules of vitamin A, while α-carotene provides one upon central cleavage. This study shows a very clear association between α-carotene and body fatness, which appears to go beyond its fat-soluble nature. Dietary intake data were not able to explain the association. Further work is needed to determine what dietary components infer health benefits.

Pre-pregnancy obesity and maternal nutritional biomarker status during pregnancy: a factor analysis

OBJECTIVE

Pre-pregnancy obesity has been associated with adverse birth outcomes. Poor essential fatty acid (EFA) and micronutrient status during pregnancy may contribute to these associations. We assessed the associations between pre-pregnancy BMI and nutritional patterns of maternal micronutrient and EFA status during mid-pregnancy.

DESIGN

A cross-sectional analysis from a prospective cohort study. Women provided non-fasting blood samples at ≥ 20 weeks’ gestation that were assayed for red cell EFA; plasma folate, homocysteine and ascorbic acid; and serum retinol, 25-hydroxyvitamin D, a-tocopherol, soluble transferrin receptors and carotenoids. These nutritional biomarkers were employed in a factor analysis and three patterns were derived: EFA, Micronutrients and Carotenoids.

SETTING

The Antidepressant Use During Pregnancy Study, Pittsburgh, PA, USA.

SUBJECTS

Pregnant women (n 129).

RESULTS

After adjustment for parity, race/ethnicity and age, obese pregnant women were 3.0 (95% CI 1.1, 7.7) times more likely to be in the lowest tertile of the EFA pattern and 4.5 (95% CI 1.7, 12.3) times more likely to be in the lowest tertile of the Carotenoid pattern compared with their lean counterparts. We found no association between pre-pregnancy obesity and the Micronutrient pattern after confounder adjustment.

CONCLUSIONS

Our results suggest that obese pregnant women have diminished EFA and carotenoid concentrations.

Relationships of body mass index with serum carotenoids, tocopherols and retinol at steady-state and in response to a carotenoid-rich vegetable diet intervention in Filipino schoolchildren

In marginally nourished children, information is scarce regarding the circulating concentrations of carotenoids and tocopherols, and physiological factors influencing their circulating levels. We determined the serum concentrations of carotenoids, tocopherols and retinol at steady state and in response to a 9-week vegetable diet intervention in 9-12-year-old girls (n=54) and boys (n=65) in rural Philippines. We determined cross-sectional relationships of BMI (body mass index) with serum micronutrient levels, and whether BMI is a determinant of serum carotenoid responses to the ingestion of carotenoid-rich vegetables. We measured dietary nutrient intakes and assessed inflammation by measurement of serum C-reactive protein levels. The children had low serum concentrations of carotenoids, tocopherols and retinol as compared with published values for similar-aged children in the U.S.A. The low serum retinol levels can be ascribed to inadequate diets and were not the result of confounding due to inflammation. Significant inverse correlations of BMI and serum all-trans-beta-carotene, 13-cis-beta-carotene, alpha-carotene, lutein, zeaxanthin and alpha-tocopherol (but not beta-cryptoxanthin, lycopene and retinol) were observed among girls at baseline. The dietary intervention markedly enhanced the serum concentrations of all carotenoids. Changes in serum all-trans-beta-carotene and alpha-carotene (but not changes in lutein, zeaxanthin and beta-cryptoxanthin) in response to the dietary intervention were inversely associated with BMI in girls and boys. Thus, in Filipino school-aged children, BMI is inversely related to the steady-state serum concentrations of certain carotenoids and vitamin E, but not vitamin A, and is a determinant of serum beta- and alpha-carotene responses, but not xanthophyll responses, to the ingestion of carotenoid-rich vegetable meals.

Age-related changes in plasma lycopene concentrations, but not in vitamin E, are associated with fat mass

The aim of the present study was to assess the influence of age on plasma concentration of α-tocopherol, retinol and carotenoids with a special attention paid to natural differences in body composition. Forty healthy subjects were recruited: twenty were less than 35 years old and twenty above 60 years old. Males and females were equally represented in each age group. Subjects were kept in energy balance and received controlled diets for 36 h. Fat mass and fat-free mass were determined with the180-enriched water dilution technique. Plasma vitamins A and E, and carotenoid levels were determined after 12 h fasting and were shown to be similar in women and men. Plasma α-tocopherol concentration increased with age (+44 % elderlyv.young), and correlated with % fat mass and plasma cholesterol. After adjustment for plasma cholesterol, the effect of age and % fat mass disappeared. In contrast, plasma lycopene level was 2-fold lower in the elderly than in the young group, and was inversely correlated with fat mass. When lycopene values were adjusted for fat mass, the effect of age disappeared. These results suggest that plasma levels of vitamin E and lycopene differed in the two age groups and that differences in plasma cholesterol and fat mass might participate in such an effect. Short-term vitamin intake did not appear to influence plasma vitamin concentrations.

Absorption of lycopene from single or daily portions of raw and processed tomato

To study the relationship between lycopene intake and plasma concentration, ten healthy female subjects were given one or more portions of tomato purée or fresh raw tomato containing 16.5mg total lycopene (all-trans + cis forms). In Expt 1 subjects (n 9) were randomly assigned the single portions of the two tomato products and blood samples were collected to follow the change in plasma carotenoid concentrations within the first 12 h and on each of the following 5 d (104 h). In Expt 2 subjects (n 10) were divided into two groups of five each receiving daily dietary portions of tomato purée or fresh raw tomato containing 16.5mg total lycopene for 7 d. Fasting blood samples were collected daily. In Expt 1 the plasma total lycopene (all-trans + cis forms) concentration, after the single portions of tomato purée and raw tomato, varied significantly over time, with a first peak reached after 6 h, a further increase after 12 h and a slow decrease until 104 h. In Expt 2, when the tomato products were given daily, there was a day-by-day increase in the plasma total lycopene concentration, and through the following week of a diet without tomato there was a gradual decrease. However, values did not return to basal concentrations. Plasma total lycopene concentration was higher after the tomato purée intake than after the raw tomato in both the first (F (1,8) 7.597; P < 0.025) and the second experiments (F (1,8) 12.193; P < 0.01) demonstrating a significant effect of food matrix on absorption.

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

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

Diet and Serum Carotenoid Concentrations Affect Macular Pigment Optical Density in Adults 45 Years and Older

The dietary carotenoids lutein (L) and zeaxanthin (Z) are the principal components of macular pigment (MP). Protection of the central retina by MP is suggested, but data are limited. Dietary practices and serum carotenoid concentrations were investigated in 98 adults, 45-73 y old, in relation to MP. Macular pigment optical density (MPOD) was measured at 4 loci: 10 min (10', 30 min (30'), 60 min (60'), and 120 min (120') retinal eccentricity. Serum L + Z concentrations in fasting subjects were correlated with MPOD: 10' (r = 0.29, P = 0.008), 30' (r = 0.342, P = 0.0006), and 60' (r = 0.73, P = 0.001) eccentricity. Dietary L + Z was positively correlated with MPOD: 10' (r = 0.24, P = 0.02), 30' (r = 0.237, P = 0.02), 60' (r = 0.27, P = 0.009), and 120' (r = 0.25, P = 0.02) eccentricity. The lowest fruit and vegetable consumers had lower MPOD at 30' (P = 0.01), 60' (P = 0.03), and 120' (P = 0.006) eccentricity compared with the highest consumers. Based on age quartiles (45-49 y), (50-55 y), (56-61 y), and (62-74 y), the youngest and oldest had higher MPOD than those 56-61 y at 60' (P < 0.05). Compared with those with a BMI (kg/m(2)) >/= 27, those with a BMI < 27 had higher serum concentrations of beta-carotene (P = 0.002), and higher MPOD at 60' (P = 0.04) and 120' (P = 0.01). These findings suggest that carotenoid-rich diets and serum carotenoids positively contribute to MP status.

Correlates of serum lutein + zeaxanthin: findings from the Third National Health and Nutrition Examination Survey

The determinants of blood levels of carotenoids were previously investigated in small or select samples. The relations of serum lutein + zeaxanthin to possible diet, lifestyle, and physiological determinants in 7059 participants of the Third National Health and Nutrition Examination Survey (1988-1994), > or = 40 y old, were examined. In a fully adjusted, multiple linear regression model, lower serum lutein + zeaxanthin was significantly associated with smoking, heavy drinking, being white, female, or not being physically active, having lower dietary lutein + zeaxanthin, higher fat-free mass, a higher percentage of fat mass, a higher waist-hip ratio, lower serum cholesterol, a higher white blood cell count, and high levels of C-reactive protein (P < 0.05). The model explained 24% of the variation present in serum lutein + zeaxanthin for the current sample. The correlation between dietary and serum lutein + zeaxanthin was 0.17 and increased to 0.18 after adjusting for the effects of given covariates. Each 10% increase in dietary lutein + zeaxanthin was associated with a 1% increase in serum conditional on other terms in the model. Many factors that influence the level of serum lutein + zeaxanthin remain unknown.

Consumption of watermelon juice increases plasma concentrations of lycopene and beta-carotene in humans

Watermelon is a rich natural source of lycopene, a carotenoid of great interest because of its antioxidant capacity and potential health benefits. Assessment of bioavailability of lycopene from foods has been limited to tomato products, in which heat processing promotes lycopene bioavailability. We examined the bioavailability of lycopene from fresh-frozen watermelon juice in a 19-wk crossover study. Healthy, nonsmoking adults (36-69 y) completed three 3-wk treatment periods, each with a controlled, weight-maintenance diet. Treatment periods were preceded by "washout" periods of 2-4 wk during which lycopene-rich foods were restricted. All 23 subjects consumed the W-20 (20.1 mg/d lycopene, 2.5 mg/d beta-carotene from watermelon juice) and C-0 treatments (controlled diet, no juice). As a third treatment, subjects consumed either the W-40 (40.2 mg/d lycopene, 5.0 mg/d beta-carotene from watermelon juice, n = 12) or T-20 treatment (18.4 mg/d lycopene, 0.6 mg/d beta-carotene from tomato juice, n = 10). After 3 wk of treatment, plasma lycopene concentrations for the W-20, W-40, T-20 and C-0 treatments were (least squares means +/- SEM) 1078 +/- 106, 1183 +/- 139, 960 +/- 117 and 272 +/- 27 nmol/L, respectively. Plasma concentrations of beta-carotene were significantly greater after W-20 (574 +/- 49 nmol/L) and W-40 (694 +/- 73 nmol/L) treatments than after the C-0 treatment (313 +/- 27 nmol/L). Plasma lycopene concentrations did not differ at wk 3 after W-20, W-40 and T-20 treatments, indicating that lycopene was bioavailable from both fresh-frozen watermelon juice and canned tomato juice, and that a dose-response effect was not apparent in plasma when the watermelon dose was doubled.

Serum carotenoid concentrations in US children and adolescents

BACKGROUND

Carotenoids, a class of phytochemicals, may affect the risk of several chronic conditions.

OBJECTIVE

Our objective was to describe the distributions and correlates of serum carotenoid concentrations in US children and adolescents.

DESIGN

Using data from the third National Health and Nutrition Examination Survey (1988-1994), a cross-sectional study, we examined the distributions of serum concentrations of alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein and zeaxanthin, and lycopene among 4231 persons aged 6-16 y.

RESULTS

After adjustment for age, sex, race or ethnicity, poverty-income ratio, body mass index status, HDL- and non-HDL-cholesterol concentrations, C-reactive protein concentration, and cotinine concentration, only HDL-cholesterol (P < 0.001) and non-HDL-cholesterol (P < 0.001) concentrations were directly related to all carotenoid concentrations. Age (P < 0.001) and body mass index status (P < 0.001) were inversely related to all carotenoid concentrations except those of lycopene. Young males had slightly higher carotenoid concentrations than did young females, but the differences were significant only for lycopene concentrations (P = 0.029). African American children and adolescents had significantly higher beta-cryptoxanthin (P < 0.001), lutein and zeaxanthin (P < 0.001), and lycopene (P = 0.006) concentrations but lower alpha-carotene (P < 0.001) concentrations than did white children and adolescents. Mexican American children and adolescents had higher alpha-carotene (P < 0.001), beta-cryptoxanthin (P < 0.001), and lutein and zeaxanthin (P < 0.001) concentrations but lower lycopene (P = 0.001) concentrations than did white children and adolescents. C-reactive protein concentrations were inversely related to beta-carotene (P < 0.001), lutein and zeaxanthin (P < 0.001), and lycopene (P = 0.023) concentrations. Cotinine concentrations were inversely related to alpha-carotene (P = 0.002), beta-carotene (P < 0.001), and beta-cryptoxanthin (P < 0.001) concentrations.

CONCLUSION

These data show significant variations in serum carotenoid concentrations among US children and adolescents and may be valuable as reference ranges for this population.

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

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

Lycopene: chemistry, biology, and implications for human health and disease

A diet rich in carotenoid-containing foods is associated with a number of health benefits. Lycopene provides the familiar red color to tomato products and is one of the major carotenoids in the diet of North Americans and Europeans. Interest in lycopene is growing rapidly following the recent publication of epidemiologic studies implicating lycopene in the prevention of cardiovascular disease and cancers of the prostate or gastrointestinal tract. Lycopene has unique structural and chemical features that may contribute to specific biological properties. Data concerning lycopene bioavailability, tissue distribution, metabolism, excretion, and biological actions in experimental animals and humans are beginning to accumulate although much additional research is necessary. This review will summarize our knowledge in these areas as well as the associations between lycopene consumption and human health.