Tomato consumption and plasma lycopene concentration in people aged 65 y and over in a British national survey

Lycopene destabilizes preformed Aβ fibrils: Mechanistic insights from all-atom molecular dynamics simulation

The therapeutic strategy employing destabilization of the preformed Aβ fibril by various natural compounds, as studied by experimental and computational methods, has been reported significant in curing Alzheimer's disease (AD). However, lycopene (a carotenoid), from terpenes family, needs investigation for its destabilization potential of Aβ fibril. The highest antioxidant potential and ability to cross blood brain barrier makes lycopene a preferred choice as drug lead for treating AD. The current study focuses on investigating the destabilization potential and underpinning mechanism of lycopene on different polymorphic forms of Aβ fibril via Molecular Dynamics (MD) simulation. The key findings highlight binding of lycopene to the outer surface of the chain F of the fibril (2NAO). Herein G9, K16 and V18 residues were found to be involved in van der Waals with the methyl groups of the lycopene. Additionally, Y10 and F20 residues were observed to interact via π-π interactions with CC bonds of the lycopene. The surface mediated binding of lycopene to the fibril is attributed to the large size and structural rigidity of lycopene along with the bulky size of 2NAO and narrow space of fibrillar cavity. The destabilization of the fibril is evident by breakage of inherent H-bonds and hydrophobic interactions in the presence of one lycopene molecule. The lesser β-sheet content explains disorganization of the fibril and bars the higher order aggregation curbing neurotoxicity of the fibril. The higher concentration of the lycopene is not found to be linearly correlated with the extent of destabilization of the fibril. Lycopene is also observed to destabilize the other polymorphic form of Aβ fibril (2BEG), by accessing the fibrillar cavity and lowering the β-sheet content. The destabilization observed by lycopene on two major polymorphs of Aβ fibril explains its potency towards developing an effective therapeutic approach in treating AD.

A narrative review on the potential of tomato and lycopene for the prevention of Alzheimer's disease and other dementias

Oxidative stress is a major factor in aging and is implicated in the pathogenesis of tumors, diabetes mellitus, cardiovascular and neurodegenerative diseases, including Alzheimer Disease (AD). Bioactive constituents of tomato as polyphenols and carotenoids, among which lycopene (LYC) are effective in reducing markers of oxidative stress, and appear to have a protective modulator role on the pathogenetic mechanisms, cognitive symptoms and behavioral manifestations of these diseases in cell cultures and animal models. Epidemiological evidence indicates a consistent association between the intake of tomatoes and reduced cardiovascular and neoplastic risk. LYC deficiency is common in elders and AD patients and it is strongly predictive of mortality and poor cardiovascular (CV) outcomes. Dietary intake of tomatoes seems to be more effective than tomato/LYC supplementation. Limited evidence from human intervention trials suggests that increasing tomato intake, besides improving CV markers, enhances cognitive performances. In this narrative review, we analyze the existing evidence on the beneficial effects of tomatoes on AD-related processes or risk factors. Results support the development of promising nutritional strategies to increase the levels of tomato consumption for the prevention or treatment of AD and other dementias. Extensive well-structured research, however, is mandatory to confirm the neuroprotective effects of tomato/LYC in humans.

Lower serum levels of alpha tocopherol and lycopene are associated with higher pain and physical disability in subjects with primary knee osteoarthritis: A case-control study

Background: We aimed to determine dietary intake and serum concentration of α-tocopherol and lycopene in subjects with knee osteoarthritis (KOA) in relation to pain intensity and functional status and comparing them with healthy controls. Methods: This case-control study was conducted among 35 patients with primary KOA and 35 matched healthy subjects selected using convenience sampling method. Dietary intakes of alpha-tocopherol and lycopene were estimated from 24-hour dietary records. Visual Analogue Scale (VAS) and Western Ontario and McMaster (WOMAC) index were used to assess the pain and functional status, respectively. Results: Serum concentrations of alpha-tocopherol (0.024 ± 0.005 vs. 0.028 ± 0.007 μmol/ml, p-value =  0.021) and lycopene (0.616 ± 0.191 vs. 0.727 ± 0.159 μmol/l, p-value = 0.011) were significantly lower in OA patients in comparison with healthy controls. Dietary intake of alpha-tocopherol was negatively associated with total WOMAC score (r = -0.401, p-value = 0.021) and pain (r = -0.356, p-value = 0.042) and physical function (r = -0.355, p-value = 0.043) subscales. Dietary intake of lycopene was negatively associated with total WOMAC score (r = -0.616, p-value < 0.001) and pain (r = -0.348, p-value = 0.047) and physical function (r = -0.606, p-value < 0.001) subscales. Additionally, serum concentration of alpha-tocopherol was negatively associated with total WOMAC score (r = -0.574, p-value < 0.001) and physical function subscale (r = -0.571, p-value < 0.001). Serum concentration of lycopene was negatively associated with total WOMAC score (r = -0.360, p-value = 0.040) and physical function subscale (r = -0.350, p-value = 0.046) Conclusion: Serum concentrations of α-tocopherol and lycopene were significantly lower in patients with KOA than in healthy controls. Significant negative association was detected between serum concentration and dietary intake of α-tocopherol and lycopene with functional disability in patients with KOA.

Lycopene and cognitive function

Decreases in cognitive function related to increases in oxidative stress and inflammation occur with ageing. Acknowledging the free radical-quenching activity and anti-inflammatory action of the carotenoid lycopene, the aim of the present review was to assess if there is evidence for a protective relationship between lycopene and maintained cognitive function or between lycopene and development or progression of dementia. A systematic literature search identified five cross-sectional and five longitudinal studies examining these outcomes in relation to circulating or dietary lycopene. Among four studies evaluating relationships between lycopene and maintained cognition, three reported significant positive relationships. Neither of the two studies reporting on relationship between lycopene and development of dementia reported significant results. Of four studies investigating circulating lycopene and pre-existing dementia, only one reported significant associations between lower circulating lycopene and higher rates of Alzheimer's disease mortality. Acknowledging heterogeneity among studies, there is insufficient evidence and a paucity of data to draw firm conclusions or tease apart direct effects of lycopene. Nevertheless, as low circulating lycopene is a predictor of all-cause mortality, further investigation into its relationship with cognitive longevity and dementia-related mortality is warranted.

Fractionation and Characterization of Lycopene-Oxidation Products by LC-MS/MS (ESI)+: Elucidation of the Chemopreventative Potency of Oxidized Lycopene in Breast-Cancer Cell Lines

Lycopene (LYC) has been correlated with the reduction of certain cancers and chronic diseases. However, the existence and biofunctionality of degraded, oxidized, and biotransformed LYC products in vivo have not been revealed. Therefore, this study aimed to screen and elucidate the potential bioactive lycopene-derived products in breast-cancer and non-cancerous cells. LYC-oxidation or -cleavage products were generated using KMnO₄. These oxidation products were separated as fractions I-III by silica column chromatography using gradient solvent systems. Further, LC-MS/MS (ESI)⁺ was used to elucidate their possible fragmentation patterns and structures. Fraction II showed higher cytotoxicity (IC₅₀ value of 64.5 μM), cellular uptake, and apoptosis-inducing activity in MCF-7 cells. This fraction consists of major peak m/ z 323, identified as apo-8,6'-carotendial. The cytotoxicity-inducing activity may be due to partial ROS generation with mitochondrial dysfunction. Further, the role of apo-8,6'-carotendial in the induction of apoptosis is demonstrated for the first time. These results illustrated that LYC-oxidation derivatives or metabolites are involved in growth inhibition of cancer cells. Exploration of specific oxidized-carotenoid products will give further insight into the field of nutritional biochemistry.

Validation of biomarkers of food intake-critical assessment of candidate biomarkers

Biomarkers of food intake (BFIs) are a promising tool for limiting misclassification in nutrition research where more subjective dietary assessment instruments are used. They may also be used to assess compliance to dietary guidelines or to a dietary intervention. Biomarkers therefore hold promise for direct and objective measurement of food intake. However, the number of comprehensively validated biomarkers of food intake is limited to just a few. Many new candidate biomarkers emerge from metabolic profiling studies and from advances in food chemistry. Furthermore, candidate food intake biomarkers may also be identified based on extensive literature reviews such as described in the guidelines for Biomarker of Food Intake Reviews (BFIRev). To systematically and critically assess the validity of candidate biomarkers of food intake, it is necessary to outline and streamline an optimal and reproducible validation process. A consensus-based procedure was used to provide and evaluate a set of the most important criteria for systematic validation of BFIs. As a result, a validation procedure was developed including eight criteria, plausibility, dose-response, time-response, robustness, reliability, stability, analytical performance, and inter-laboratory reproducibility. The validation has a dual purpose: (1) to estimate the current level of validation of candidate biomarkers of food intake based on an objective and systematic approach and (2) to pinpoint which additional studies are needed to provide full validation of each candidate biomarker of food intake. This position paper on biomarker of food intake validation outlines the second step of the BFIRev procedure but may also be used as such for validation of new candidate biomarkers identified, e.g., in food metabolomic studies.

Cardiovascular benefits of lycopene: fantasy or reality?

Epidemiological evidence indicates that high consumption of tomatoes and tomato-based products reduces the risk of chronic diseases such as CVD and cancer. Such potential benefits are often ascribed to high concentrations of lycopene present in tomato products. Mainly from the results of in vitro studies, potential biological mechanisms by which carotenoids could protect against heart disease and cancer have been suggested. These include cholesterol reduction, inhibition of oxidation processes, modulation of inflammatory markers, enhanced intercellular communication, inhibition of tumourigenesis and induction of apoptosis, metabolism to retinoids and antiangiogenic effects. However, with regard to CVD, results from intervention studies gave mixed results. Over fifty human intervention trials with lycopene supplements or tomato-based products have been conducted to date, the majority being underpowered. Many showed some beneficial effects but mostly on non-established cardiovascular risk markers such as lipid peroxidation, DNA oxidative damage, platelet activation and inflammatory markers. Only a few studies showed improvement in lipid profiles, C reactive protein and blood pressure. However, recent findings indicate that lycopene could exert cardiovascular protection by lowering HDL-associated inflammation, as well as by modulating HDL functionality towards an antiatherogenic phenotype. Furthermore, in vitro studies indicate that lycopene could modulate T lymphocyte activity, which would also inhibit atherogenic processes and confer cardiovascular protection. These findings also suggest that HDL functionality deserves further consideration as a potential early marker for CVD risk, modifiable by dietary factors such as lycopene.

Plasma Lycopene Is Associated with Pizza and Pasta Consumption in Middle-Aged and Older African American and White Adults in the Southeastern USA in a Cross-Sectional Study

BACKGROUND

The role of dietary lycopene in chronic disease prevention is not well known.

METHODS

This study examined intake of lycopene and other antioxidants from lycopene-rich foods (e.g., pizza and pasta) simultaneously with plasma levels of lycopene and other antioxidants in a representative cross-sectional sample (187 Blacks, 182 Whites, 40-79 years old) from the Southern Community Cohort Study (SCCS). The SCCS is an ongoing study conducted in populations at high risk for chronic diseases living in Southeastern United States. Dietary intake was assessed using a validated food frequency questionnaire (FFQ), and plasma levels of lycopene and other antioxidants were measured at baseline (2002-2005). The participants were classified into tertiles according to consumption of pizza and pasta food groups.

RESULTS

Lycopene dietary intake and plasma lycopene concentrations were significantly higher in the highest (tertile 3) compared to tertiles 1 and 2 (both P < 0.01). Total energy intake ranged from 1964.3 ± 117.1 kcal/day (tertile 1) to 3277.7 ± 115.8 kcal/day (tertile 3) (P<0.0001). After adjusting for age and energy intake, total dietary fat, saturated fatty acids, trans-fatty acids, and sodium intakes were significantly higher in tertile 3 than tertiles 2 and 1 (all P <0.01). Vitamin C intake was significantly lower in tertile 3 than tertiles 1 and 2 (P = 0.003). Except for γ-tocopherol being higher in tertile 3 than tertiles 1 and 2 (P = 0.015), the plasma concentrations of antioxidants were lower in tertile 3 than tertiles 1 and 2 (β-carotene, α-carotene, lutein and zeaxanthin, all P<0.05).

CONCLUSIONS

In the SCCS population, pizza and pasta were the main sources of dietary lycopene and their intake was associated with plasma lycopene concentration. Diets with frequent pizza and pasta consumption were high in energy, saturated fatty acids, trans-fatty acids, sodium and low in other antioxidants. Future studies of lycopene as a protective dietary factor against chronic disease should consider the overall nutritional quality of lycopene-containing foods.

Lycopene Deficiency in Ageing and Cardiovascular Disease

Lycopene is a hydrocarbon phytochemical belonging to the tetraterpene carotenoid family and is found in red fruit and vegetables. Eleven conjugated double bonds predetermine the antioxidant properties of lycopene and its ability to scavenge lipid peroxyl radicals, reactive oxygen species, and nitric oxide. Lycopene has a low bioavailability rate and appears in the blood circulation incorporated into chylomicrons and other apo-B containing lipoproteins. The recent body of evidence suggests that plasma concentration of lycopene is not only a function of intestinal absorption rate but also lycopene breakdown via enzymatic and oxidative pathways in blood and tissues. Oxidative stress and the accumulation of reactive oxygen species and nitric oxide may represent a major cause of lycopene depletion in ageing, cardiovascular disease, and type 2 diabetes mellitus. It has been shown recently that low carotenoid levels, and especially decreased serum lycopene levels, are strongly predictive of all-cause mortality and poor outcomes of cardiovascular disease. However, there is a poor statistical association between dietary and serum lycopene levels which occurs due to limited bioavailability of lycopene from dietary sources. Hence, it is very unlikely that nutritional intervention alone could be instrumental in the correction of lycopene and carotenoid deficiency. Therefore, new nutraceutical formulations of carotenoids with enhanced bioavailability are urgently needed.

Protection against chemotaxis in the anti-inflammatory effect of bioactives from tomato ketchup

The consumption of tomato products has been associated with a decreased risk for chronic inflammatory diseases. In this study, the anti-inflammatory potential of tomato ketchup was evaluated by studying the effect of tomato ketchup extracts and bioactives from tomato ketchup on human monocytes and vascular endothelial cells (HUVEC). HUVEC were pre-treated for 1 h with either individual bioactives (7.5 µM lycopene, 1.4 µM α-tocopherol or 55 µM ascorbic acid) or a combination of these three compounds, or with the hydrophilic or lipophilic tomato ketchup extracts or with the two extracts combined. After the pretreatment, the cells were washed and challenged with TNF-α (10 ng/ml) for 6 h. The medium was used for the determination of the release of cytokines and the chemotaxis of monocytes. Inflammatory protein expression and production were assayed with real-time RT-PCR and ELISA. It was found that tomato ketchup extracts significantly reduced gene expression and release of the pro-inflammatory cytokines TNF-α and IL-8 in HUVEC after the inflammatory challenge, whereas the release of the anti-inflammatory cytokine IL-10 was increased. Chemotaxis was effectively impeded as demonstrated by a reduced monocyte migration. This effect correlated with the reduction of IL-8 production in the presence of the test compounds and extracts. The results consistently emphasize the contribution of lycopene to the anti-inflammatory effect of tomato ketchup. Other compounds in tomato ketchup such as α-tocopherol and ascorbic acid appeared to strengthen the anti-inflammatory effect of lycopene. The tomato ketchup extracts subtly interfered with several inflammatory phases that inhibit chemotaxis. Such a pleotropic mode of action exemplifies its potential mitigation of diseases characterized by prolonged low grade inflammation.

Whole food versus supplement: comparing the clinical evidence of tomato intake and lycopene supplementation on cardiovascular risk factors

Cardiovascular disease (CVD) is a major contributor to morbidity and mortality in the United States and worldwide. A link between diet and CVD is well established, with dietary modification a foundational component of CVD prevention and management. With the discovery of bioactive components beyond the essential nutrients of foods, a new era of nutritional, medical, botanical, physiologic, and analytical sciences has unfolded. The ability to identify, isolate, purify, and deliver single components has expanded the dietary supplement business and health opportunity for consumers. Lycopene is an example of a food component that has attracted attention from scientists as well as food, agriculture, and dietary supplement industries. A major question, however, is whether delivering lycopene through a supplement source is as effective as or more effective than consuming lycopene through whole food sources, specifically the tomato, which is the richest source of lycopene in the Western diet. In this review, we examined clinical trials comparing the efficacy of lycopene supplements with tomato products on intermediate CVD risk factors including oxidative stress, inflammation, endothelial function, blood pressure, and lipid metabolism. Overall, the present review highlights the need for more targeted research; however, at present, the available clinical research supports consuming tomato-based foods as a first-line approach to cardiovascular health. With the exception of blood pressure management where lycopene supplementation was favored, tomato intake provided more favorable results on cardiovascular risk endpoints than did lycopene supplementation. Indeed, future research that is well designed, clinically focused, mechanistically revealing, and relevant to human intake will undoubtedly add to the growing body of knowledge unveiling the promise of tomatoes and/or lycopene supplementation as an integral component of a heart-healthy diet.

Tomato Consumption and Health: Emerging Benefits

Tomatoes and tomato products are one of the most familiar vegetables in the American diet. Quantitatively, they are the most consumed nonstarchy vegetable and are the most significant source of dietary lycopene; a powerful antioxidant that has greater bioavailability after cooking and processing (eg, canning). A large body of research supports an inverse relationship between consuming tomatoes and tomato products and risk of certain cancers, while emerging research is exploring the protective relationship between tomato intake and a host of conditions, including cardiovascular disease, osteoporosis, ultraviolet light—induced skin damage, and cognitive dysfunction. Initial studies of tomato consumption and disease risk reduction focused on lycopene and antioxidant activity. More recent hypotheses recognize the advantages of the whole tomato; and hence, research on the role of tomato products in health and disease risk reduction extends beyond antioxidant function to include other protective mechanisms such as antithrombotic and anti-inflammatory functions. Increasing daily vegetable intake in the American diet offers the potential to yield significant health benefits. In addition to the specific benefits of tomato consumption, encouraging greater tomato and tomato product consumption may help increase overall vegetable intake because of their wide availability, well-established acceptability, cost-effectiveness, and convenience of multiple forms. Leveraging emerging science about tomatoes and tomato products may be one simple and effective strategy to help individuals increase vegetable intake, leading to improved overall eating patterns, and ultimately, better health.

Geographical location has greater impact on carotenoid content and bioaccessibility from tomatoes than variety

The suggested health benefits of consuming tomatoes and tomato-based products have been attributed, in part, to the carotenoids present in these foods. Therefore, the objectives of the present study were to (i) analyse carotenoid content and bioaccessibility from different tomato (Lycopersicon esculentum L.) types namely cherry, plum, round, and certain tomatoes-on-the-vine; and (ii) determine if geographical location (Ireland vs Spain) influenced the content and bioaccessibility of carotenoids in tomatoes of the same variety. Carotenoid bioaccessibility is defined as the amount of ingested carotenoids that, after digestion, are available for absorption by intestinal cells. Differences were seen in carotenoid content and bioaccessibility between the different tomato types tested. For instance, Irish round high-lycopene tomatoes contained the greatest amounts of lycopene and lutein but lowest levels of beta-carotene compared with the other Irish tomatoes. Furthermore, the content and bioaccessibility of carotenoids that were sourced from Ireland and Spain also varied greatly. Spanish tomatoes were generally superior in the content, bioaccessibility, and micelle content of carotenoids. To conclude, our findings suggest that geographical location, rather than the type of tomato, seems to have a more pronounced effect on carotenoid bioaccessibility from tomatoes.

Lycopene enrichment of cultured airway epithelial cells decreases the inflammation induced by rhinovirus infection and lipopolysaccharide

Rhinovirus infection results in increased release of inflammatory mediators from airway epithelial cells in asthma. As an antioxidant, lycopene offers protection from adverse effects of inflammation. The aim of this study was to find an appropriate method of lycopene enrichment of airway epithelial cells and to determine the effects of lycopene enrichment on the inflammatory response of cells infected by rhinovirus or exposed to lipopolysaccharide. Lycopene enrichment of airway epithelial cells using solubilisation in tetrahydrofuran versus incorporation in liposomes was compared. After determining that solubilisation of lycopene in tetrahydrofuran was the most suitable method of lycopene supplementation, airway epithelial cells (Calu-3) were incubated with lycopene (dissolved in tetrahydrofuran) for 24 h, followed by rhinovirus infection or lipopolysaccharide exposure for 48 h. The release of interleukin-6, interleukin-8 and interferon-gamma induced protein-10 (IP-10) and their messenger RNA levels were measured using enzyme linked immunosorbent assay and reverse transcription polymerase chain reaction, respectively. Viral replication was measured by tissue culture infective dose of 50% assay. Lycopene concentration of cells and media were analysed using high-performance liquid chromatography. Preincubation of airway epithelial cells with lycopene (dissolved in tetrahydrofuran) delivered lycopene into the cells and resulted in a 24% reduction in interleukin-6 after rhinovirus-1B infection, 31% reduction in IP-10 after rhinovirus-43 infection and 85% reduction in rhinovirus-1B replication. Lycopene also decreased the release of IL-6 and IP-10 following exposure to lipopolysaccharide. We conclude that lycopene has a potential role in suppressing rhinovirus induced airway inflammation.

Reduced growth and integrin expression of prostate cells cultured with lycopene, vitamin E and fish oil in vitro

Integrins are transmembrane proteins that facilitate the interaction of cells with the extracellular environment. They have also been implicated in cancer progression. The effects of nutrients thought to be involved in the prevention of prostate cancer on integrin expression have not been determined. Prostate cancer cell lines representing a range of malignancy from normal (RWPE-1) to highly invasive phenotypes (22Rv1 < LNCaP < PC-3) were cultured with or without lycopene (10 nm), vitamin E (5 μm) or fish oil (100 μm) for 48 h. Growth and integrin (α2β1, αvβ3 and αvβ5) expression were assessed using Trypan Blue exclusion and monoclonal antibodies combined with flow cytometry. Vitamin E enhanced (P < 0·001) whereas fish oil reduced the growth of all the cell lines tested (P < 0·001). Lycopene had no effect on growth. All the malignant cell lines exhibited lower expression of α2β1 with the addition of lycopene to culture media. Supplemental fish oil reduced α2β1 in most invasive cell lines (LNCaP and PC-3). Each nutrient at physiological levels reduced integrins αvβ3 and αvβ5 in most invasive cell lines (PC-3). The results suggest that integrins may represent an additional target of bioactive nutrients and that the effects of nutrients may be dependent on the type of cell line used.

Hispanic and non-Hispanic white elders from Massachusetts have different patterns of carotenoid intake and plasma concentrations

Carotenoids have been linked with protective roles against diseases associated with aging, including cancer, cardiovascular disease, cataracts, and age-related macular degeneration. With data from a semiquantitative, validated FFQ, we examined carotenoid intake of 340 Puerto Ricans, 98 Dominicans, and 146 non-Hispanic whites (>60 y old) in Massachusetts. Compared with non-Hispanic white men, Hispanic men reported a higher intake of lycopene and lower intakes of alpha-carotene, lutein + zeaxanthin, beta-carotene (from diet only), and total beta-carotene (diet and supplements) (P < 0.001). Hispanic women reported higher intakes of beta-cryptoxanthin and lycopene but lower intakes of lutein + zeaxanthin (P < 0.001) than non-Hispanic white women. The frequency of consumption of fruit and vegetables was higher among Hispanic women, relative to non-Hispanic white women (P < 0.05). Plasma concentrations of alpha-carotene and lycopene were higher in Hispanic than in non-Hispanic white men and women. For both ethnic groups, higher intakes of carotenoids were associated with higher plasma concentrations of the respective carotenoids, except for lycopene (Hispanics) and lutein + zeaxanthin (non-Hispanic whites). Food sources contributing most to total intakes differed among the groups. The major sources of alpha- and beta-carotene were carrots for non-Hispanic whites and winter squash for Hispanics. The major source of lycopene was cooked tomato products for Hispanics, and pasta dishes for non-Hispanic whites. Traditional foods such as beans and plantains were also important contributors of carotenoids for Hispanics. Because of the potential importance of carotenoids as protective factors against chronic diseases, more attention to food-related practices associated with carotenoid intake in differing population groups is warranted.

Plasma lycopene, other carotenoids, and retinol and the risk of cardiovascular disease in men

BACKGROUND

Emerging evidence suggests a possible role of lycopene in the primary prevention of cardiovascular disease (CVD).

OBJECTIVE

We examined whether plasma lycopene concentrations in the Physicians' Health Study were associated with CVD in a prospective, nested, case-control design.

DESIGN

Baseline blood samples were collected starting in 1996. During a mean follow-up of 2.1 y, we identified 499 cases of CVD (confirmed myocardial infarction, stroke, CVD death, or revascularization procedures) and an equal number of men free of CVD and matched for age (x: 69.7 y), follow-up time, and smoking status. We collected self-reported coronary disease risk factors and measured plasma carotenoids, retinol, lipids, and C-reactive protein.

RESULTS

In matched analyses with additional adjustment for plasma total cholesterol and randomized treatment, the relative risks (RRs) of CVD for men in the lowest to highest quartiles of plasma lycopene were 1.00 (reference), 0.92, 1.04, and 0.95 (P for linear trend = 0.93). With multivariate adjustment, the RRs of total CVD were 1.00 (reference), 1.08, 0.94, and 1.03 (P for linear trend = 0.98). For important vascular events (241 cases), excluding revascularization procedures, the multivariate RRs remained nonsignificant (P for linear trend = 0.50). Adding plasma carotenoids, lipids, or C-reactive protein to multivariate models had a minimal effect on the RRs of total CVD for plasma lycopene. Compared with lycopene, higher concentrations of plasma lutein/zeaxanthin and retinol suggested a moderate increase in CVD risk, whereas no association was found for beta-cryptoxanthin, alpha-carotene, and beta-carotene.

CONCLUSIONS

Higher plasma lycopene concentrations were not associated with the risk of CVD in this study of older men. Further evaluation in diverse populations is necessary.

Population determinants of serum lycopene concentrations in the United States: data from the Third National Health and Nutrition Examination Survey, 1988-1994

Serum lycopene is inversely related to the risk for cancer and cardiovascular diseases. We used data from the Third National Health and Nutrition Examination Survey, 1988-1994, to investigate the relation between serum lycopene concentrations and sex, age, geographical location, race-ethnicity, education, alcohol, smoking, BMI, blood pressure, serum total cholesterol and triacylglycerol, and intakes of fat, tomatoes and tomato-based products in 3413 individuals aged 17-90 y. Multivariate adjusted mean lycopene concentrations were 48.3% lower in individuals > or =70 y old than in those 17 to <30 y old (P < 0.0001), 7.6% lower in women than in men (P = 0.0045), 15.1% lower in people living in the South than those in the West (P < 0.0001), 10.3 and 61.0% lower in the 1st quartile than in the 4th quartile for dietary fat intake (P = 0.0173) and serum cholesterol (P < 0.0001), respectively, 11.1% lower in tomato noneaters than those who ate tomatoes > or =31 times/mo (P = 0.0085), 13.5% lower in pizza noneaters than those who ate pizza > or =16 times/mo (P = 0.0016), and 20.6% lower in pasta noneaters than those who ate pasta (with tomato sauce) > or =16 times/mo (P < 0.0001). Race-ethnicity, alcohol, BMI, blood pressure, and consumption of non-tomato vegetables, and fruits and juices had no association with serum lycopene concentrations. Sex, age, geographical region, socioeconomic status, serum total cholesterol, smoking, and intakes of fat, tomatoes, pizza, and pasta were significant determinants of serum lycopene concentrations in the United States.