Intakes of fruits, vegetables, and related vitamins and lung cancer risk: results from the Shanghai Men's Health Study (2002-2009)

Impact of antioxidants on PM2.5 oxidative potential, radical level, and cytotoxicity

Antioxidants are typically seen as agents that mitigate environmental health risks due to their ability to scavenge free radicals. However, our research presents a paradox where these molecules, particularly those within lung fluid, act as prooxidants in the presence of airborne particulate matter (PM2.5), thus enhancing PM2.5 oxidative potential (OP). In our study, we examined a range of antioxidants found in the respiratory system (e.g., vitamin C, glutathione (GSH), and N-acetylcysteine (NAC)), in plasma (vitamin A, vitamin E, and β-carotene), and in food (tert-butylhydroquinone (TBHQ)). We aimed to explore antioxidants' prooxidant and antioxidant interactions with PM2.5 and the resulting OP and cytotoxicity. We employed OH generation assays and electron paramagnetic resonance assays to assess the pro-oxidative and anti-oxidative effects of antioxidants. Additionally, we assessed cytotoxicity interaction using a Chinese hamster ovary cell cytotoxicity assay. Our findings revealed that, in the presence of PM2.5, all antioxidants except vitamin E significantly increased the PM2.5 OP by generating more OH radicals (OH generation rate: 0.16-24.67 pmol·min-1·m-3). However, it's noteworthy that these generated OH radicals were at least partially neutralized by the antioxidants themselves. Among the pro-oxidative antioxidants, vitamin A, β-carotene, and TBHQ showed the least ability to quench these radicals, consistent with their observed impact in enhancing PM2.5 cytotoxicity (PM2.5 LC50 reduced to 91.2 %, 88.8 %, and 75.1 % of PM2.5's original level, respectively). Notably, vitamin A and TBHQ-enhanced PM2.5 OP were strongly associated with the presence of metals and organic compounds, particularly with copper (Cu) contributing significantly (35 %) to TBHQ's pro-oxidative effect. Our study underscores the potential health risks associated with the interaction between antioxidants and ambient pollutants.

Dietary and supplementary vitamin C intake and the risk of lung cancer: A meta‑analysis of cohort studies

Previous cohort studies reported inconsistent findings regarding the association between dietary or supplementary vitamin C intake and lung cancer risk. These associations were investigated by conducting a meta-analysis of cohort studies. The PubMed and EMBASE databases were utilized, using keywords related to the topic from inception to April 15, 2022. Pooled effect sizes, such as relative risk (RR) or hazard ratio (HR) with 95% confidence intervals (CIs), were calculated using a random-effects model. A total of 20 cohort studies from 13 articles were included in the final analysis. In a meta-analysis of all studies, there was no significant association between dietary or supplementary vitamin C intake and lung cancer risk (RR/HR, 0.90; 95% CI, 0.80-1.01; I2=56.4%; n=20). In the subgroup meta-analysis by the source of vitamin C, dietary vitamin C intake decreased the risk of lung cancer (RR/HR, 0.82; 95% CI, 0.73-0.92; I2=42.5%; n=14), whereas there was no association between supplementary vitamin C intake and lung cancer risk (RR/HR, 1.01; 95% CI, 0.84-1.22; n=4). The present meta-analysis of cohort studies found that dietary vitamin C intake is beneficial for preventing lung cancer, whereas its supplementary intake does not have a beneficial effect.

Vitamin K Intake and Risk of Lung Cancer: The Japan Collaborative Cohort Study

BACKGROUND

Limited reports from prospective human studies investigated the possible role of vitamin K in the development of lung cancer although vitamin K's anticarcinogenic activities were verified from several in vitro and in vivo studies. We investigated the associations between total vitamin K intake from food and the development of lung cancer based on this large prospective cohort study.

METHODS

A validated food frequency questionnaire was used to examine vitamin K intake among 42,166 (16,341 men and 25,825 women) at the Japan Collaborative Cohort Study's baseline (1988-1990). Hazard ratios (HRs) and 95% confidence intervals (CIs) of incident lung cancer were calculated using the Cox proportional hazard regression method based on vitamin K consumption quartiles.

RESULTS

430 cases (308 males and 122 women) of lung cancer were documented during a total of 564,127 person-years of follow-up (median follow-up, 14.6 years). Vitamin K consumption was shown to be inversely related to lung cancer risk; the multivariable hazard ratio [HR] for the highest versus lowest quartiles was 0.67 (95% confidence interval [CI], 0.46-0.96; P for trend = 0.010). This relationship appears to be stronger in males (HR 0.62; 95% CI, 0.40-0.96; P for trend = 0.016) than in females (HR 0.82; 95% CI, 0.42-1.61; P for trend = 0.39) (P for interaction = 0.012), and in ever smokers (HR 0.57; 95% CI, 0.36-0.91; P for trend = 0.006) than in never smokers (HR 0.79; 95% CI, 0.40-1.55; P for trend = 0.37) (P for interaction = 0.30). The individuals' age, body mass index, or alcohol consumption status had no effect on the observed connection.

CONCLUSION

Vitamin K consumption reduces the risk of lung cancer. More research is needed to clarify the molecular processes behind this connection.

Quantity and Variety in Fruit and Vegetable Consumption and Mortality in Older Chinese: A 15-year Follow-Up of a Prospective Cohort Study

BACKGROUND

Independent associations of quantity and variety of fruit and vegetables (FVs) with mortality in older people are still unclear.

OBJECTIVES

This study aimed to explore the association between the quantity and variety in FV consumption and mortality in older Chinese.

METHODS

A total of 19,597 participants of the Guangzhou Biobank Cohort Study aged >50 y were recruited from 2003 to 2006 and followed up until April 2021. The diet was assessed using a 300-item validated FFQ. Variety as a continuous variable was defined as the number of unique FV items (excluding potatoes, legumes, and fruit juices) intake per week over the past week. The associations of quantity and variety of FVs with mortality were analyzed, and analyses by the color of edible parts was performed. Multivariable Cox regression yielded HRs and 95% CIs.

RESULTS

During 286,821 person-year of follow-up, 4385 deaths occurred, including 1678 cardiovascular diseases (CVD), 1450 cancer, and 1257 other causes. Compared with the lowest quintile of variety in FV, the highest quintile was associated with lower risks of all-cause (HR: 0.81; 95% CI: 0.73-0.89) and CVD mortality (HR: 0.79; 95% CI 0.67-0.92). A greater variety of green and white FV intake was associated with lower risks of all-cause and CVD morality, and a greater variety of red/purple FV intake was associated with lower risks of all-cause and cancer mortality. However, the quantity of FV intake showed no association with all-cause, CVD, and cancer mortality.

CONCLUSION

Our findings have first showed that the variety, rather than quantity, in FV intake was associated with a lower risk of mortality in older Chinese. Dietary guidelines may recommend increasing the variety in FV intake, especially green, red/purple, and white FVs in older people.

Overexpressing Carotenoid Biosynthetic Genes in Synechocystis sp. PCC 6803 Improved Intracellular Pigments and Antioxidant Activity, Which Can Decrease the Viability and Proliferation of Lung Cancer Cells In Vitro

In the antioxidant system in cyanobacteria, non-enzymatic antioxidants, such as carotenoids, are considered good candidates for coping with oxidative stress, particularly light stress, and pharmaceutical therapeutic applications. A significant amount of carotenoid accumulation has been recently improved by genetic engineering. In this study, to achieve higher carotenoid production with higher antioxidant activity, we successfully constructed five Synechocystis sp. PCC 6803 strains overexpressing (OX) native genes related to the carotenoids biosynthetic pathway, including OX_CrtB, OX_CrtP, OX_CrtQ, OX_CrtO, and OX_CrtR. All of the engineered strains maintained a significant quantity of myxoxanthophyll, while increasing zeaxanthin and echinenone accumulation. In addition, higher components of zeaxanthin and echinenone were noted in all OX strains, ranging from 14 to 19% and from 17 to 22%, respectively. It is worth noting that the enhanced echinenone component responded to low light conditions, while the increased β-carotene component contributed to a high light stress response. According to the higher antioxidant activity of all OX strains, the carotenoid extracts presented lower IC₅₀ in lung cancer cell lines H460 and A549, with values less than 157 and 139 µg/mL, respectively, when compared with those of WTc, particularly OX_CrtR and OX_CrtQ. A higher proportion of zeaxanthin and β-carotene in OX_CrtR and OX_CrtQ, respectively, may considerably contribute to the ability to treat lung cancer cells with antiproliferative and cytotoxic effects.

Carotenoids for lung cancer chemoprevention and chemotherapy: Promises and controversies

BACKGROUND

Lung cancer is one of the leading causes of malignancy in the world. Several therapeutical and chemopreventive approaches have been practised to mitigate the disease. The use of phytopigments including carotenoids is a well-known approach. However, some of the prominent clinical trials interrogated the efficacy of carotenoids in lung cancer prevention.

METHODS

A elaborate literature survey have been performed investigating in vitro, in vivo, and clinical studies reported on the administration of carotenoids for chemoprevention and chemotherapy.

RESULTS

Tobacco consumption, genetic factors, dietary patterns, occupational carcinogens, lung diseases, infection, and sex disparities are some of the prominent factors leading to lung cancer. Significant evidence has been found underlining the efficiency of carotenoids in alleviating cancer. In vitro studies have proven that carotenoids act through PI3K/ AKT/mTOR, ERK-MAPK pathways and induce apoptosis through PPAR, IFNs, RAR, which are p53 intermediators in lung cancer signaling. Animal models and cell lines studies showed promising results, while the outcomes of clinical trials are contradictory and require further verification.

CONCLUSION

The carotenoids exert chemotherapeutic and chemopreventive effects on lung tumors which has been evidenced in numerous investigations. However, further analyses are necessary to the answer the uncertainties raised by several clinical trials.

Environment and chronic disease in rural areas of Heilongjiang, China (ECDRAHC)

PURPOSE

Environmental factors such as long-term exposure to cold can increase the risk of chronic diseases. However, few studies have focused on the impact of environmental factors and lifestyle changes on chronic diseases. To fully explore the association between exposure to environmental factors and the prevalent risk of various chronic diseases, we conducted a large cohort study (Environment and Chronic Disease in Rural Areas of Heilongjiang, China (ECDRAHC)). The ECDRAHC collected detailed questionnaire data covering 10 sections, physical measurements and blood and urine samples. In this study, we describe the design and implementation of the cohort study and present the findings for the first 10 000 participants.

PARTICIPANTS

The ECDRAHC study was carried out in rural areas where the annual average temperature is 2.9°C, and aimed to recruit 40 000 participants who are long-term residents aged 35-74 years. The participants will be followed up every 5 years. Currently, ECDRAHC has reached 26.7% (n=10 694) of the targeted population.

FINDINGS TO DATE

A total of 10 694 adults aged 35-74 years were recruited, including 61.7% women. The prevalence of current smokers was 46.8% in men and 35.4% in women. The mean blood pressure was 140.2/89.9 mm Hg and 135.7/85.0 mm Hg in men and women, respectively. The mean body mass index was 24.74 kg/m² in men and 24.65 kg/m² in women, with >7.3% being obese (>30 kg/m²). The main non-communicable diseases found in phase 1 were hypertension, diabetes, hypertriglyceridaemia and metabolic syndrome, with a higher prevalence of 51.0%, 21.6%, 46.8% and 42.6%, respectively.

FUTURE PLANS

We plan to complete the follow-up for the first phase of the ECDRAHC in 2024. The second and third phase of the cohort will be carried out steadily, as planned. This cohort will be used to investigate the relationship between environmental factors, lifestyle, and genetic and common chronic diseases.

Watermelon Intake Is Associated with Increased Nutrient Intake and Higher Diet Quality in Adults and Children, NHANES 2003-2018

Watermelon is a nutrient-dense, low energy food that provides vital nutrients and contributes to overall fruit intake. Previous studies have found positive associations between watermelon and nutrient intake but few focused on raw watermelon intake or had small sample sizes. Therefore, the objective of this study was to utilize a large, nationally representative sample to determine associations between watermelon intake and nutrient intake and diet quality. Data from children (2-18 y) and adults (19+ y) who participated in the National Health and Nutrition Examination Survey (NHANES) cycles 2003-2018 were utilized in the current study. Watermelon intake was 7.51 and 7.29 g/d per capita in children and adults, respectively. In watermelon consumers, usual intake was 125 and 161 g/d in children and adults, respectively. Total diet quality was higher in watermelon consumers as compared to non-consumers as well as several subcomponent scores. Children and adult watermelon consumers had greater than 5% higher intake of dietary fiber, magnesium, potassium, and vitamin A as well as more than 5% lower intake of added sugars and total saturated fatty acids as well as higher intake of lycopene and other carotenoids. This study suggests watermelon can increase nutrient intake as well as diet quality in both children and adult Americans.

Dietary Carotenoids in Head and Neck Cancer-Molecular and Clinical Implications

Head and neck cancer (HNC) is one of the most common cancers in the world according to GLOBCAN. In 2018, it was reported that HNC accounts for approximately 3% of all human cancers (51,540 new cases) and is the cause of nearly 1.5% of all cancer deaths (10,030 deaths). Despite great advances in treatment, HNC is indicated as a leading cause of death worldwide. In addition to having a positive impact on general health, a diet rich in carotenoids can regulate stages in the course of carcinogenesis; indeed, strong epidemiological associations exist between dietary carotenoids and HNS, and it is presumed that diets with carotenoids can even reduce cancer risk. They have also been proposed as potential chemotherapeutic agents and substances used in chemoprevention of HNC. The present review discusses the links between dietary carotenoids and HNC. It examines the prospective anticancer effect of dietary carotenoids against intracellular cell signalling and mechanisms, oxidative stress regulation, as well as their impact on apoptosis, cell cycle progression, cell proliferation, angiogenesis, metastasis, and chemoprevention; it also provides an overview of the limited preclinical and clinical research published in this arena. Recent epidemiological, key opinion-forming systematic reviews, cross-sectional, longitudinal, prospective, and interventional studies based on in vitro and animal models of HNC also indicate that high carotenoid content obtained from daily supplementation has positive effects on the initiation, promotion, and progression of HNC. This article presents these results according to their increasing clinical credibility.

Causal associations between dietary antioxidant vitamin intake and lung cancer: A Mendelian randomization study

Background

Oxidative stress is currently considered to be closely related to the occurrence of respiratory tumors, especially lung cancer. Many observational studies have shown that increased antioxidant intake can reduce the risk of lung cancer, but the results are still controversial. Therefore, we performed a two-sample Mendelian randomized (MR) analysis to clarify the causal relationship between antioxidant vitamins and lung cancer.

Methods

To assess the causal effect of dietary antioxidant vitamin intake on lung cancer, we conducted a two-sample MR analysis and we extracted single-nucleotide polymorphisms (SNPs) that are associated with antioxidants from genome-wide association studies (GWASs) of the UK biobank. We gathered summary data for lung cancer from the International Lung Cancer Consortium (ILCCO), including 11,348 cases and 15,861 controls, and applied the inverse-variance weighted (IVW) method as the primary MR analysis, and performed a sensitivity analysis to verify the results.

Results

The results showed that higher dietary retinol intake was causally associated with lung cancer overall [odds ratio (OR) = 1.844, 95% CI, 1.359-2.502, p = 0.00009], squamous cell lung cancer (OR = 2.162, 95% CI, 1.117-4.183, p = 0.022), and lung adenocarcinoma (OR = 1.706, 95% CI, 1.084-2.685, p = 0.021). Additionally, carotene was positively correlated with lung adenocarcinoma (OR = 1.510, 95% CI, 1.002-2.276, p = 0.049). However, there was a non-significant relationship between the intake of other dietary antioxidants (vitamin C and vitamin E) and lung cancer.

Conclusion

Our research showed that dietary retinol intake has an adverse impact on lung cancer, and carotene might increase the risk of adenocarcinoma. This highlights the importance of revealing the underlying mechanisms of dietary antioxidant vitamins in lung cancer and delivers an important health message that dietary antioxidant vitamin intake may not be necessary for the prevention of lung cancer. It also provides a basis for future research.

Physiological Effects of Green-Colored Food-Derived Bioactive Compounds on Cancer

Green-colored foods, such as broccoli, sprouts, soybean, and green leafy vegetables are considered one of the representative healthy foods for containing various functional ingredients that can combat chronic diseases, including diabetes, obesity, and cancer. Herein, we reviewed the anti-cancer activities and the underlying mechanisms of some important bioactive compounds, such as sulforaphane, catechins, chlorophyll, isoflavone, indole dervatives, and lutein, present in green-colored foods. In vivo and clinical studies suggest that sulforaphane, a sulfur-containing compound found in cruciferous vegetables, can ameliorate prostate and breast cancer symptoms by arresting cell-cycle progression and modulating Ki67 and HDAC expression. A green tea compound, known as epigallocatechin-3-gallate (EGCG), has shown remarkable anti-cancer effects against prostate cancer and lung adenocarcinoma in human trials through its antioxidative defense and immunomodulatory functions. Chlorophyll, a natural pigment found in all green plants, can regulate multiple cancer-related genes, including cyclin D1, CYP1A, CYP1B1, and p53. Epidemiological studies indicate that chlorophyll can substantially reduce aflatoxin level and can mitigate colon cancer in human subjects. Remarkably, the consumption of soy isoflavone has been found to be associated with the lower incidence and mortality of breast and prostate cancers in East Asia and in Canada. In vivo and in vitro data point out that isoflavone has modulatory effects on estrogen and androgen signaling pathways and the expression of MAPK, NfκB, Bcl-2, and PI3K/AKT in different cancer models. Other green food bioactive compounds, such as indole derivatives and lutein, also exhibited suppressing effects in rodent models of lung, liver, stomach, cervical, and prostate cancers. In addition, some micronutrients, such as folate, riboflavin, retinoic acid, and vitamin D3 present in green foods, also showed potential cancer suppressing effects. Taken together, these data suggest potential chemopreventive functions of the bioactive compounds from green-colored foods. This paper could be beneficial for further research on the anti-carcinogenic effects of green-colored food-derived compounds, in order to develop green chemotherapeutics for cancers.

Phytochemicals from Indian Ethnomedicines: Promising Prospects for the Management of Oxidative Stress and Cancer

Oxygen is indispensable for most organisms on the earth because of its role in respiration. However, it is also associated with several unwanted effects which may sometimes prove fatal in the long run. Such effects are more evident in cells exposed to strong oxidants containing reactive oxygen species (ROS). The adverse outcomes of oxidative metabolism are referred to as oxidative stress, which is a staple theme in contemporary medical research. Oxidative stress leads to plasma membrane disruption through lipid peroxidation and has several other deleterious effects. A large body of literature suggests the involvement of ROS in cancer, ageing, and several other health hazards of the modern world. Plant-based cures for these conditions are desperately sought after as supposedly safer alternatives to mainstream medicines. Phytochemicals, which constitute a diverse group of plant-based substances with varying roles in oxidative reactions of the body, are implicated in the treatment of cancer, aging, and all other ROS-induced anomalies. This review presents a summary of important phytochemicals extracted from medicinal plants which are a part of Indian ethnomedicine and Ayurveda and describes their possible therapeutic significance.

Antitumor Effects of Astaxanthin on Esophageal Squamous Cell Carcinoma by up-Regulation of PPARγ

Esophageal squamous cell carcinoma is a malignant tumor that is difficult to find and has a poor prognosis. The aim of this study is to explore the chemoprevention effect of Astaxanthin (AST) and reveal the possible mechanism of AST on the development of esophageal cancer based on PPARγ. We found that a stable and strong binding between PPARγ molecules and AST molecules using Autodock 4.0 software. AST significantly inhibited the viability of EC109 cells in a dose and time dependent manners (all P < 0.05), and up-regulated the protein expression level of PPARγ from the concentration of 6.25 µM (P < 0.05). Animal experiment showed that AST significantly decreased the incidences of NMBzA-induced esophageal carcinogenesis at 50 mg/kg AST in F344 rats (P < 0.05). AST inhibited the oxidative stress by improving the levels of superoxide dismutase (SOD), total antioxidant capacity (TAOC) and suppressing malondialdehyde (MDA) in serum, and increasing the protein of PPARγ, Bax/Bcl-2, Caspase-3 in esophagus tissue, especially in the 50 mg/kg of AST intervention group (all P < 0.05). In conclusion, our data suggested that protective effect of AST on esophageal cancer by inhibiting oxidative stress, up-regulating PPARγ, and activating the apoptotic pathway, which could provide a basis for clinical application of AST.

Circulating vitamin C concentration and risk of cancers: a Mendelian randomization study

BACKGROUND

Circulating vitamin C concentrations have been associated with several cancers in observational studies, but little is known about the causal direction of the associations. This study aims to explore the potential causal relationship between circulating vitamin C and risk of five most common cancers in Europe.

METHODS

We used summary-level data for genetic variants associated with plasma vitamin C in a large vitamin C genome-wide association study (GWAS) meta-analysis on 52,018 Europeans, and the corresponding associations with lung, breast, prostate, colon, and rectal cancer from GWAS consortia including up to 870,984 participants of European ancestry. We performed two-sample, bi-directional Mendelian randomization (MR) analyses using inverse-variance-weighted method as the primary approach, while using 6 additional methods (e.g., MR-Egger, weighted median-based, and mode-based methods) as sensitivity analysis to detect and adjust for pleiotropy. We also conducted a meta-analysis of prospective cohort studies and randomized controlled trials to examine the association of vitamin C intakes with cancer outcomes.

RESULTS

The MR analysis showed no evidence of a causal association of circulating vitamin C concentration with any examined cancer. Although the odds ratio (OR) per one standard deviation increase in genetically predicted circulating vitamin C concentration was 1.34 (95% confidence interval 1.14 to 1.57) for breast cancer in the UK Biobank, this association could not be replicated in the Breast Cancer Association Consortium with an OR of 1.05 (0.94 to 1.17). Smoking initiation, as a positive control for our reverse MR analysis, showed a negative association with circulating vitamin C concentration. However, there was no strong evidence of a causal association of any examined cancer with circulating vitamin C. Sensitivity analysis using 6 different analytical approaches yielded similar results. Moreover, our MR results were consistent with the null findings from the meta-analysis exploring prospective associations of dietary or supplemental vitamin C intakes with cancer risk, except that higher dietary vitamin C intake, but not vitamin C supplement, was associated with a lower risk of lung cancer (risk ratio: 0.84, 95% confidence interval 0.71 to 0.99).

CONCLUSIONS

These findings provide no evidence to support that physiological-level circulating vitamin C has a large effect on risk of the five most common cancers in European populations, but we cannot rule out very small effect sizes.

Possible Biochemical Processes Underlying the Positive Health Effects of Plant-Based Diets-A Narrative Review

Plant-based diets are becoming more popular for many reasons, and epidemiological as well as clinical data also suggest that a well-balanced vegan diet can be adopted for the prevention, and in some cases, in the treatment of many diseases. In this narrative review, we provide an overview of the relationships between these diets and various conditions and their potential biochemical background. As whole plant foods are very rich in food-derived antioxidants and other phytochemicals, they have many positive physiological effects on different aspects of health. In the background of the beneficial health effects, several biochemical processes could stand, including the reduced formation of trimethylamine oxide (TMAO) or decreased serum insulin-like growth factor 1 (IGF-1) levels and altered signaling pathways such as mechanistic target of rapamycin (mTOR). In addition, the composition of plant-based diets may play a role in preventing lipotoxicity, avoiding N-glycolylneuraminic acid (Neu5Gc), and reducing foodborne endotoxin intake. In this article, we attempt to draw attention to the growing knowledge about these diets and provide starting points for further research.

Biofortified orange corn increases xanthophyll density and yolk pigmentation in egg yolks from laying hens

Plant breeding has developed corn genotypes with grain higher in levels of carotenoids. Dietary consumption of specific carotenoids by humans has been associated with improved eye health, notably with some protection against age-related macular degeneration. Increasing dietary sources of macular carotenoids in the standard American diet might be accomplished by using high carotenoid Orange Corn in poultry diets to increase macular carotenoid concentrations in egg yolks. Three hundred sixty laying hens (Novogen White) were fed three different diets over 31 days. Each diet had six replicates of 20 hens housed in enrichable colony cages. The only difference was the type of corn included - white, yellow, and orange, in order to assess the impact of each type of corn on egg production, yolk pigmentation, and carotenoid deposition. This study assessed yolk color and carotenoid densities using a portable colorimeter and the DSM YolkFan, and by high performance liquid chromatography (HPLC) on eggs from the feeding study and on 43 cartons of 12 eggs commercially available and produced in various production settings: conventional cage, cage-free, cage-free organic, free-range/pasture, and free-range/pasture organic. Yolks from hens fed with the Orange Corn diet produced eggs with higher (P < 0.01) DSM yolk color (6 to 10) and total xanthophylls (23.5 to 35.3 μg/g of egg yolk) compared to the yellow diet (5 to 6 DSM and 12.3 to 17.7 μg/g xanthophylls) and white diet (1 to 2 DSM and 2.5 to 3.0 μg/g xanthophylls). Egg yolks reached a maximum xanthophyll accumulation with the Orange Corn diet (35.3 μg/g of egg yolk) after twelve days of treatment and maintained steady levels at subsequent time points. In general, xanthophyll levels in yolks from the Orange Corn diet were superior (30–61% higher) to any of the commercial egg brands, suggesting that feeding high carotenoid Orange Corn increases xanthophyll density in eggs.

Citrus fruit intake and lung cancer risk: A meta-analysis of observational studies

OBJECTIVE

To explore the hypothesis that Citrus intake may reduce the risk of lung cancer.

DESIGN

Meta-analyses of Dichotomy and dose-response relationship.

DATA SOURCES

We searched online literature databases including PubMed, Embase, and Cochrane Library to screen relevant articles available up to 27 July 2020. Search terms included (i) Citrus, Fruit, Diet, Dietary; (ii) cancer, neoplasm, tumor (iii)lung; (iv)case-control, cohort, prospective.

STUDY SELECTION

The selection of studies and the meta-analysis were carried out by following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The following inclusion criteria were chosen: (i) epidemiological studies with case-control or cohort design; (ii) human participants; (iii) studies investigated the relationship between Citrus fruit intake and lung cancer risk; (iv) if data were duplicated in more than two studies, we brought the most recent or all-sided study into this analysis. We collected all full-text articles that met the inclusion criteria. We applied the following exclusion criteria to the full-text articles, including possible articles listed by manual search: (i) there was no represented odds ratio (OR) or relative risk (RR) estimate and its corresponding 95 % confidence interval (95 % CI) (or data to calculate them) for the highest versus lowest levels of Citrus fruit consumption (ii) reviews, systematic reviews and meta-analyses; (iii) there was no data of Citrus fruit intake at the individual level.

DATA EXTRACTION

Two reviewers independently performed the extraction of data from eligible studies.

STATISTICAL METHODS

Adjusted odds ratios (ORs) and 95 % CIs were combined and weighted by the method of "Dersimonian and Laird" to produce pooled ORs using a random-effects model. Moreover, we utilized the method reported by "Longnecker and Greenland" to evaluate linear trends and 95 % CIs by the ORs' natural logs and corresponding CIs from categories of Citrus intake. Finally, we evaluated the risk of publication bias and selection bias by inspecting for asymmetry in the pre-specified funnel plots of the study OR against the standard error of the OR's logarithm and by "Egger's test".

RESULTS

We included twenty-one studies in the final review. Pooled analyses suggested that those with the highest Citrus fruit intake compared to the lowest intake had a 9% reduction in lung cancer risk [OR 0.91 (95 % CI 0.84-0.98)]. We found a nonlinear association between Citrus intake and lung cancer risk in the dose-response analysis (p = 0.0054) and that the risk reached the minimum (OR = 0.91) around 60 g/d. However, no obvious dose-response association was observed with intakes above 80 g/d.

CONCLUSION

We found that Citrus fruit intake was negatively associated with the risk of lung cancer. Besides, there was a nonlinear dose-response relationship between Citrus intake and lung cancer risk within a certain range.

Dietary carotenoids in cancer chemoprevention and chemotherapy: A review of emerging evidence

In recent years, natural products have reemerged as biotherapeutic options, with several dietary carotenoids, viz. astaxanthin, fucoxanthin, siphonaxanthin, β-cryptoxanthin, α-carotene, β-carotene, and lycopene, developing as potential candidates for chemoprevention and chemotherapeutics of breast, colorectal, lung, and prostate cancers. The potent cytotoxic and antiproliferative effects of carotenoids against various cancer cells are mediated by a wide range of molecular mechanisms modulating oxidative stress and redox balance, mitogen-activated protein kinases (MAPK) and other cellular signaling proteins, transcription factors, caspase cascade pathways of apoptosis, cell cycle progression and proliferation, angiogenesis, metastasis, gap junction intercellular communication (GJIC), and multidrug resistance (MDR). This review discusses recent evidence demonstrating the crucial roles of carotenoids in these cellular and molecular events of cancer cell cytotoxicity. In addition, recent case-control and cohort studies are discussed to support the potential role of carotenoids in cancer prevention and therapy.

Association of Lung Cancer and Tea-Drinking Habits of Different Subgroup Populations: Meta-Analysis of Case-Control Studies and Cohort Studies

BACKGROUND

We aimed to investigate the association between lung cancer and tea-drinking habits of different subgroup populations.

METHODS

Systematic search of the PubMed, Web of Science, China National Knowledge Infrastructure (CNKI) and Sinomed databases from database construction until January 2017 for English and Chinese language articles on association of lung cancer and tea drinking. Meta-analysis was used to calculate the combined odds ratio (OR) value and its 95% confidence interval (95% CI). The Newcastle-Ottawa scale was used to evaluate the quality of the studies and Q-test and I₂ was used for heterogeneity testing.

RESULTS

Forty two papers were included, 30 case-control studies included 14578 lung cancer patients and 180574 controls, 12 cohort studies included 543825 subjects, of which the outcome was 5085 with lung cancer. Tea drinkers were found to have a decreased OR of lung cancer compared with non-tea drinkers (OR 0. 80, 95% CI: 0. 73, 0. 87). Consumption of green, black or unspecified tea has a protective effect compared with not drinking tea at all. Increased intake of green tea to 7. 5 g per day can further reduce the OR of lung cancer (OR 0. 69, 95% CI: 0. 48-0. 98). Tea consumption had a protective effect against lung cancer in non-smokers, Further analysis found that drinking of one or more cups of tea a day has a protective effect on smokers (OR 0. 79, 95% CI: 0. 64-0. 96).

CONCLUSION

Tea drinking could be a protective factor in lung cancer.

Food intake of folate, folic acid and other B vitamins with lung cancer risk in a low-income population in the Southeastern United States

PURPOSE

We prospectively examined associations of lung cancer risk with food intake of B vitamins involved in one-carbon metabolism and the use of folic acid-containing supplements among a low-income population of black and white adults in the Southeastern US.

METHODS

Within the Southern Community Cohort Study, we included 1064 incident lung cancer cases among 68,236 participants aged 40-79 years at study enrollment. Food intake and the use of folic acid-containing supplements were assessed using a validated food frequency questionnaire at study enrollment. Multivariate Cox regression was used to estimate hazards ratios (HRs) and the 95% confidence intervals (CIs).

RESULTS

Folate and/or folic acid intake from food were not associated with lung cancer risk; HRs (95% CI) for highest compared with lowest quartile were 1.08 (0.91-1.29) for total dietary folate, 1.00 (0.84-1.19) for food folate, and 1.09 (0.91-1.30) for food folic acid, respectively. Similarly, no associations were observed after stratifying by sex, race and smoking status, except for a positive association with total dietary folate intake among black women (HR 1.46, 95% CI 1.04-2.05 for the highest quartile compared with the lowest quartile, P trend = 0.02). Neither the use of folic acid-containing supplements nor food intake of vitamin B₆, vitamin B₁₂ and riboflavin were associated with lung cancer risk.

CONCLUSIONS

Our findings do not support a protective effect of folate or folic acid for lung cancer prevention in a low-income population of black and white adults in the Southeastern US. Our finding of a positive association with total dietary folate intake among black women needs to be interpreted with caution and replicated in other studies.

Identification and Quantification of Carotenoids and Tocochromanols in Sorghum Grain by High-Performance Liquid Chromatography

Carotenoids and tocochromanols are lipid-soluble secondary plant metabolites that are essential for the normal functioning of plants and, in some cases function as a source of vitamin A and E in humans. Enhancement of the provitamin A carotenoid and tocochromanols levels in sorghum and other cereal grains through traditional breeding and transgenic methods has increased in recent years with interest in biofortification of grains to combat micronutrient deficiencies in developing countries. With this increase in research, reliable methodology for the extraction, identification, and quantification of individual carotenoids and tocochromanols species from sorghum and other cereal grains is essential. Here, we describe a basic method for extraction of carotenoid and tocochromanols adapted to sorghum grain and chromatographic condition for separation, identification, and quantification of individual carotenoid using High-Performance Liquid Chromatography (HPLC) system.

The Role of Cruciferous Vegetables and Isothiocyanates for Lung Cancer Prevention: Current Status, Challenges, and Future Research Directions

Lung cancer remains a leading cause of cancer-related deaths in the United States. Although smoking and air pollution exposure are primary risk factors of lung cancer, diet has also been reported to contribute to lung cancer risk. Cruciferous vegetables contain many bioactive compounds that alter the detoxification process of air-borne carcinogenic compounds and, thereby, may decrease lung cancer risk. In the meta-analysis of 31 observational studies, cruciferous vegetable intake is inversely associated with lung cancer risk (summary odds ratio/relative risk = 0.81 and 95% confidence interval = 0.74-0.89 for comparing the highest with lowest intake categories). More observational studies need to measure urinary isothiocyanate (ITC) concentrations and investigate their association with lung cancer risk in populations with relatively high intake of cruciferous vegetables. Current evidence is limited to two phase 2 clinical trials with incomplete reporting. Hence, more short-term clinical phase 2 trials need to examine effects of various amounts and types of cruciferous vegetables on biomarkers of risk and efficacy before a large phase 3 trial can be conducted to assess effects upon lung cancer risk. This would help further elucidate whether the inverse association observed with self-reported cruciferous vegetable intake is indeed due to ITC content or other bioactive compounds.

Cruciferous vegetable intake and mortality in middle-aged adults: A prospective cohort study

BACKGROUND & AIMS

Cruciferous vegetables contain isothiocyanates, which effectively reduce inflammation and oxidative stress related to chronic diseases, inhibit the bioactivation of procarcinogens, and enhance the excretion of carcinogens. However, at present, no large cohort studies have investigated the effect of cruciferous vegetable on mortality. We aimed to examine the association between cruciferous vegetable intake and all-cause mortality, namely cancer, heart disease, cerebrovascular disease, and injuries, in a large cohort study conducted between 1990 and 1993, in Japan.

METHODS

The analysis included 88,184 participants (age: 45-74 years) with no history of cancer, myocardial infarction, and stroke. Participants were tracked for a median of 16.9 years, during which 15,349 deaths were occurred. The association between cruciferous vegetable intake and risk of all-cause and cause-specific mortality was determined by Cox proportional hazard regression analysis to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs), after adjustment for potential confounding factors.

RESULTS

An inverse association was found between cruciferous vegetable intake and total mortality in both gender. HRs (95% CI) for all-cause mortality in the highest compared to the lowest quintile were 0.86 (0.80, 0.93) for men (P = 0.0002 for trend) and 0.89 (0.81, 0.98) for women (P = 0.03 for trend). Cruciferous vegetable intake was associated with lower cancer mortality in men, as well as with heart disease-, cerebrovascular disease-, and injury-related mortality in women.

CONCLUSIONS

This prospective study suggests that a higher cruciferous vegetables intake is associated with reduced risk of all-cause mortality.

Dietary consumption of antioxidant vitamins and subsequent lung cancer risk: The Japan Public Health Center-based prospective study

While many epidemiological studies have studied the association between lung cancer risk and fruits and vegetable consumption (the major sources of antioxidant vitamins), only a few have investigated the direct association with antioxidants in consideration of cancer subtypes and smoking status. Here, we examined the association between consumption of antioxidant vitamins and lung cancer risk in one of the largest prospective cohort studies in Japan. We investigated the association of dietary antioxidant vitamins intake, namely retinol, vitamin C, vitamin E, α-carotene, and β-carotene and subsequent incidence of lung cancer among 38,207 men and 41,498 women in the Japan Public Health Center-based prospective study. Cox proportional hazard regression was performed with adjustment for potential confounders and by strata of cancer subtypes and smoking status. Antioxidant and other dietary intakes were assessed using a food frequency questionnaire (FFQ). During 1,233,096 person-years of follow-up between 1995 and 2013, a total of 1,690 lung cancer cases were newly diagnosed. In a multivariate regression model, while higher retinol intake was positively associated with overall lung cancer risk in men (HR 1.26; 95% CI 1.05-1.51; p_trend  = 0.003), the estimates were more evident with small cell carcinoma (HR 1.92; 95% CI 1.13-3.24; p_trend  < 0.001). Null associations were observed for other antioxidant vitamins. Our prospective study suggests that higher consumption of retinol may be associated with an increased risk of lung cancer in men, especially with small cell carcinoma, although confirmation is required.

Consumption of a High Quantity and a Wide Variety of Vegetables Are Predicted by Different Food Choice Motives in Older Adults from France, Italy and the UK

BACKGROUND

Consumption of a high quantity and wide variety of vegetables is currently recommended for health. Dietary variety can be low, however, particularly for older adults. This study investigated the affective factors associated with the quantity and variety of vegetables consumed by older adults in France, Italy and the UK.

METHODS

Adults aged 65 years plus completed questionnaires on self-reported vegetable intake (quantity and variety), liking for vegetables, attitudes towards intake, and demographic variables.

RESULTS

In 497 older adults (France, n = 187, Italy, n = 152, UK, n = 158), higher quantities of vegetables consumed were associated with a higher age, affluence score and liking for vegetables, and a lower importance in consumption of familiarity (smallest β = 0.11, p = 0.03). Greater variety was associated with a higher liking and importance of health benefits, and a lower importance of familiarity (smallest β = -0.11, p < 0.01). Higher quantity and variety combined (quantity × variety) was associated with a higher age, liking and importance of health benefits, and a lower importance of familiarity (smallest β = 0.14, p = 0.02). Country-specific effects were also found (smallest β = 0.20, p < 0.01).

CONCLUSIONS

These findings demonstrate a role for liking and a lower concern for eating familiar foods in vegetable consumption, and a particular role for concern for health benefits in the consumption of a greater variety of vegetables.

Serum folate concentration and the incidence of lung cancer

Background

Lung cancer is a leading cause of cancer-related mortality globally. Folate helps to maintain DNA integrity and to regulate gene expression. Serum folate levels may affect the risk of several cancers, including lung cancer. In this study we evaluated the association between serum folate concentration and variations in genes involved in folate metabolism with lung cancer incidence in Poland.

Methods

The study included 366 lung cancer patients and 366 control subjects. We measured serum folate concentration and genotyped six variants in MTHFR, MTR and MTRR genes. The odds ratios of being diagnosed with lung cancer were calculated using conditional univariable and multivariable logistic regression with respect to folate level and genotypes.

Results

The mean serum folate level was lower in lung cancer cases than in control group (20.07 nmol/l vs. 22.52 nmol/l, p = 0.002). The odds ratio for lung cancer declined with increasing serum content of the folate. The folate concentration of >25.71 nmol/l (IVth quartile) in comparison to <15.92 nmol/l (Ist quartile) was associated with an odds ratio of 0.61 (95%CI 0.40–0.95, p = 0.03). The analysis of variations in MTHFR, MTR and MTRR genes did not reveal any significant difference between lung cancer cases and controls in univariable and multivariable analyses.

Conclusion

In this case-control study, lower serum folate concentrations were associated with a higher risk of lung cancer diagnosis. Although previous findings have been somewhat mixed, our results add to the evidence that circulating folate levels may be an indicator of lung cancer risk.

Inverse Association between Dietary Intake of Selected Carotenoids and Vitamin C and Risk of Lung Cancer

While diets rich in fruit and vegetables appear to reduce lung cancer risk, the evidence for individual carotenoid and vitamin intakes has been judged too limited to reach firm conclusions. Data from a case-control study of lung cancer (Montreal, QC, Canada, 1996-2002) were used to investigate the role of dietary intakes of β-carotene, α-carotene, β-cryptoxanthin, lutein/zeaxanthin, lycopene, and vitamin C in lung cancer risk. In-person interviews elicited dietary information from 1,105 incident cases and 1,449 population controls. Usual frequency of consumption of 49 fruits and vegetables 2 years prior to diagnosis/interview was collected. Odds ratios (ORs) and 95% confidence intervals (CIs) between intake variables and lung cancer were estimated using logistic or polytomous regression, adjusting for potential confounding factors including a detailed smoking history. ORs associated with upper versus lower tertiles of intake were 0.66 (95% CI = 0.51-0.84) for β-carotene, 0.70 (95% CI = 0.55-0.90) for α-carotene, 0.65 (95% CI = 0.51-0.84) for β-cryptoxanthin, 0.75 (95% CI = 0.59-0.95) for lycopene, and 0.74 (95% CI = 0.58-0.96) for vitamin C. ORs suggestive of a protective effect were found for elevated intakes of β-carotene, α-carotene, β-cryptoxanthin, and lycopene in male heavy smokers and of vitamin C in female heavy smokers. Selected antioxidants were also associated with a lower risk of lung cancer in female moderate smokers, and of squamous cell carcinoma, adenocarcinoma, and small cell carcinoma. These results suggest that several dietary antioxidants found in common food sources may protect against lung cancer, even among heavy smokers.

Fruit and vegetable consumption, Helicobacter pylori antibodies, and gastric cancer risk: A pooled analysis of prospective studies in China, Japan, and Korea

Epidemiological findings on the association between fruit and vegetable consumption and gastric cancer risk remain inconsistent. The present analysis included 810 prospectively ascertained non-cardia gastric cancer cases and 1,160 matched controls from the Helicobacter pylori Biomarker Cohort Consortium, which collected blood samples, demographic, lifestyle, and dietary data at baseline. Conditional logistic regression adjusting for total energy intake, smoking, and H. pylori status, was applied to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for gastric cancer risk across cohort- and sex-specific quartiles of fruit and vegetable intake. Increasing fruit intake was associated with decreasing risk of non-cardia gastric cancer (OR = 0.71, 95% CI: 0.52-0.95, p trend = 0.02). Compared to low-fruit consumers infected with CagA-positive H. pylori, high-fruit consumers without evidence of H. pylori antibodies had the lowest odds for gastric cancer incidence (OR = 0.12, 95% CI: 0.06-0.25), whereby the inverse association with high-fruit consumption was attenuated among individuals infected with CagA-positive H. pylori (OR = 0.82, 95% CI: 0.66-1.03). To note, the small number of H. pylori negative individuals does influence this finding. We observed a weaker, nondose-response suggestion of an inverse association of vegetable intake with non-cardia gastric cancer risk. High fruit intake may play a role in decreasing risk of non-cardia gastric cancer in Asia.

Dietary inflammatory index, Mediterranean diet score, and lung cancer: a prospective study

PURPOSE

To investigate prospectively the associations of Dietary Inflammatory Index (DII) and Mediterranean Diet Score (MDS) with lung cancer.

METHODS

We used data from men and women aged 40-69 years at recruitment in 1990-1994, who were participants in the Melbourne Collaborative Cohort Study (n = 35,303). A total of 403 incident lung cancer cases were identified over an average 18-year follow-up. Hazard ratios (HR) were estimated using Cox regression, adjusting for smoking status and other risk factors, with age as the time metric.

RESULTS

An inverse correlation was observed between the DII and MDS (ρ = -0.45), consistent with a higher DII being pro-inflammatory and less 'healthy,' while a high MDS reflects a 'healthier' diet. The DII was positively associated with risk of lung cancer in current smokers [HRQ4 vs Q1 = 1.70 (1.02, 2.82); Ptrend = 0.008] (p interaction between DII quartiles and smoking status = 0.03). The MDS was inversely associated with lung cancer risk overall [HR7-9 vs 0-3 = 0.64 (0.45, 0.90); Ptrend = 0.005] and for current smokers (HR7-9 vs 0-3 = 0.38 (0.19, 0.75); Ptrend = 0.005) (p interaction between MDS categories and smoking status = 0.31).

CONCLUSIONS

The MDS showed an inverse association with lung cancer risk, especially for current smokers. A high DII, indicating a more pro-inflammatory diet, was associated with risk of lung cancer only for current smokers. A healthy diet may reduce the risk of lung cancer, especially in smokers.

Increasing vegetable intakes: rationale and systematic review of published interventions

Purpose

While the health benefits of a high fruit and vegetable consumption are well known and considerable work has attempted to improve intakes, increasing evidence also recognises a distinction between fruit and vegetables, both in their impacts on health and in consumption patterns. Increasing work suggests health benefits from a high consumption specifically of vegetables, yet intakes remain low, and barriers to increasing intakes are prevalent making intervention difficult. A systematic review was undertaken to identify from the published literature all studies reporting an intervention to increase intakes of vegetables as a distinct food group.

Methods

Databases—PubMed, PsychInfo and Medline—were searched over all years of records until April 2015 using pre-specified terms.

Results

Our searches identified 77 studies, detailing 140 interventions, of which 133 (81 %) interventions were conducted in children. Interventions aimed to use or change hedonic factors, such as taste, liking and familiarity (n = 72), use or change environmental factors (n = 39), use or change cognitive factors (n = 19), or a combination of strategies (n = 10). Increased vegetable acceptance, selection and/or consumption were reported to some degree in 116 (83 %) interventions, but the majority of effects seem small and inconsistent.

Conclusions

Greater percent success is currently found from environmental, educational and multi-component interventions, but publication bias is likely, and long-term effects and cost-effectiveness are rarely considered. A focus on long-term benefits and sustained behaviour change is required. Certain population groups are also noticeably absent from the current list of tried interventions.

European Code against Cancer 4th Edition: Diet and cancer

Lifestyle factors, including diet, have long been recognised as potentially important determinants of cancer risk. In addition to the significant role diet plays in affecting body fatness, a risk factor for several cancers, experimental studies have indicated that diet may influence the cancer process in several ways. Prospective studies have shown that dietary patterns characterised by higher intakes of fruits, vegetables, and whole-grain foods, and lower intakes of red and processed meats and salt, are related to reduced risks of death and cancer, and that a healthy diet can improve overall survival after diagnosis of breast and colorectal cancers. There is evidence that high intakes of fruit and vegetables may reduce the risk of cancers of the aerodigestive tract, and the evidence that dietary fibre protects against colorectal cancer is convincing. Red and processed meats increase the risk of colorectal cancer. Diets rich in high-calorie foods, such as fatty and sugary foods, may lead to increased calorie intake, thereby promoting obesity and leading to an increased risk of cancer. There is some evidence that sugary drinks are related to an increased risk of pancreatic cancer. Taking this evidence into account, the 4th edition of the European Code against Cancer recommends that people have a healthy diet to reduce their risk of cancer: they should eat plenty of whole grains, pulses, vegetables and fruits; limit high-calorie foods (foods high in sugar or fat); avoid sugary drinks and processed meat; and limit red meat and foods high in salt.

Association of Dietary Vitamin A and β-Carotene Intake with the Risk of Lung Cancer: A Meta-Analysis of 19 Publications

Whether dietary β-carotene and vitamin A intake protect against lung cancer risk is not clear. Therefore, we performed this meta-analysis to investigate the association between them. The related articles were searched using the databases PubMed and the Web of Knowledge up to May 2015. We used the random-effect model to estimate the relative risk (RR) and their 95% CI. Small-study effect was assessed using Egger’s test. In total, 19 studies comprising 10,261 lung cancer cases met the inclusion criteria. The pooled RR and their 95% CI was 0.855 (0.739–0.989) for higher category of dietary vitamin A intake and lung cancer risk, especially among Asian populations and in the cohort studies. Evidence from 18 studies suggested that higher category of dietary β-carotene intake could reduce lung cancer risk (0.768 (0.675–0.874)).The associations were also significant in American and Asian populations. In conclusions, higher category of dietary β-carotene and vitamin A intakes could reduce the risk of lung cancer. However, the dose-response analysis was not performed due to the limited data in each individual study. Due to this limitation, further studies with detailed dose, cases and person-years for β-carotene and vitamin A of each category are wanted to assess this dose-response association.

Fruits, vegetables and lung cancer risk: a systematic review and meta-analysis

BACKGROUND

Lung cancer is the most common cause of cancer death. Fruits and vegetables containing carotenoids and other antioxidants have been hypothesized to decrease lung cancer risk. As part of the World Cancer Research Fund International Continuous Update Project, we conducted a systematic review and meta-analysis of prospective studies.

METHODS

We searched PubMed and several databases up to December 2014 for prospective studies. We conducted meta-analyses comparing the highest and lowest intakes and dose-response meta-analyses to estimate summary relative risks (RRs) and 95% confidence intervals (CIs), and examine possible non-linear associations. We combined results from the Pooling Project with the studies we identified to increase the statistical power of our analysis.

RESULTS

When comparing the highest with the lowest intakes, the summary RR estimates were 0.86 [95% CI 0.78-0.94; n (studies) = 18] for fruits and vegetables, 0.92 (95% CI 0.87-0.97; n = 25) for vegetables and 0.82 (95% CI 0.76-0.89; n = 29) for fruits. The association with fruit and vegetable intake was marginally significant in current smokers and inverse but not significant in former or never smokers. Significant inverse dose-response associations were observed for each 100 g/day increase: for fruits and vegetables [RR: 0.96; 95% CI 0.94-0.98, I(2) = 64%, n = 14, N (cases) = 9609], vegetables (RR: 0.94; 95% CI 0.89-0.98, I(2) = 48%, n = 20, N = 12 563) and fruits (RR: 0.92; 95% CI 0.89-0.95, I(2) = 57%, n = 23, N = 14 506). Our results were consistent among the different types of fruits and vegetables. The strength of the association differed across locations. There was evidence of a non-linear relationship (P < 0.01) between fruit and vegetable intake and lung cancer risk showing that no further benefit is obtained when increasing consumption above ∼400 g per day.

CONCLUSIONS

Eliminating tobacco smoking is the best strategy to prevent lung cancer. Although residual confounding by smoking cannot be ruled out, the current evidence from prospective studies is consistent with a protective role of fruit and vegetables in lung cancer aetiology.

Caryocar brasiliense camb protects against genomic and oxidative damage in urethane-induced lung carcinogenesis

The antioxidant effects of Caryocar brasiliense Camb, commonly known as the pequi fruit, have not been evaluated to determine their protective effects against oxidative damage in lung carcinogenesis. In the present study, we evaluated the role of pequi fruit against urethane-induced DNA damage and oxidative stress in forty 8-12 week old male BALB/C mice. An in vivo comet assay was performed to assess DNA damage in lung tissues and changes in lipid peroxidation and redox cycle antioxidants were monitored for oxidative stress. Prior supplementation with pequi oil or its extract (15 µL, 60 days) significantly reduced urethane-induced oxidative stress. A protective effect against DNA damage was associated with the modulation of lipid peroxidation and low protein and gene expression of nitric oxide synthase. These findings suggest that the intake of pequi fruit might protect against in vivo genotoxicity and oxidative stress.

The effect of fruit and vegetable intake on the development of lung cancer: a meta-analysis of 32 publications and 20,414 cases

BACKGROUND/OBJECTIVES

Quantification of the association between the intake of vegetables and fruits and the risk of lung cancer is controversial. Thus, we conducted a meta-analysis to assess the relationship between vegetables and fruits and lung cancer risk.

SUBJECTS/METHODS

Pertinent studies were identified by a search in PubMed and Web of Knowledge. Random-effects models were used to calculate summary relative risks (RR) and the corresponding 95% confidence intervals (CI). Publication bias was estimated using Begg's test.

RESULTS

Finally, 30 articles with 37 studies comprising of 20,075 lung cancer cases for vegetables intake with lung cancer risk and 31 articles with 38 studies comprising of 20,213 lung cancer cases for fruits intake with lung cancer risk were included in this meta-analysis. The combined results showed that there were significant associations between vegetables and fruits intake and lung cancer risk. The pooled RR were 0.74 (95% CI: 0.67, 0.82) for vegetables and 0.80 (95% CI: 0.74, 0.88) for fruits. Significant association was found in females on vegetables intake and lung cancer but not in males. The association was also stronger in females than males on fruits intake and lung cancer risk. No publication bias was detected.

CONCLUSIONS

Our analysis indicated that intake of vegetables and fruits may have a protective effect on lung cancer, and the associations were stronger in females. As the potential biases and confounders could not be ruled out completely in this meta-analysis, further studies are needed.

The Harbin Cohort Study on Diet, Nutrition and Chronic Non-communicable Diseases: study design and baseline characteristics

Diet and nutrition have been reported to be associated with many common chronic diseases and blood-based assessment would be vital to investigate the association and mechanism, however, blood-based prospective studies are limited. The Harbin Cohort Study on Diet, Nutrition and Chronic Non-communicable Diseases was set up in 2010. From 2010 to 2012, 9,734 participants completed the baseline survey, including demographic characteristics, dietary intake, lifestyles and physical condition, and anthropometrics. A re-survey on 490 randomly selected participants was done by using the same methods which were employed in the baseline survey. For all participants, the mean age was 50 years and 36% of them were men. Approximately 99.4 % of cohort members donated blood samples. The mean total energy intake was 2671.7 kcal/day in men and 2245.9 kcal/day in women, the mean body mass index was 25.7 kg/m² in men and 24.6 kg/m² in women, with 18.4% being obese (≥28 kg/m²), 12.7% being diabetic, and 29.5% being hypertensive. A good agreement was obtained for the physical measurements between the baseline survey and re-survey. The resources from the cohort and its fasting and postprandial blood samples collected both at baseline and in each follow-up will be valuable and powerful in investigating relationship between diet, nutrition and chronic diseases and discovering novel blood biomarkers and the metabolism of these biomarkers related to chronic diseases.

Cohort Profile: The Shanghai Men's Health Study

The Shanghai Men's Health Study (SMHS) is a population-based cohort study of 61,480 men aged 40-74 years, launched in 2002 in urban Shanghai to investigate the contribution of lifestyle/environmental factors and genetic susceptibility to cancer and other non-communicable diseases (NCDs). At baseline, trained interviewers collected detailed information on personal and dietary habits, occupational/medical history and physical activity, and took anthropometric measurements (response rate: 74%). Blood, urine and DNA were collected from 75%, 89% and 89% of participants, respectively. The cohort has been followed up through a combination of in-person surveys every 3-4 years and annual record linkage with cancer and vital statistics registries. Response rates for in-person follow-up surveys were over 91% and coverage for mortality nearly 100%. SMHS participants have a high smoking rate (58.6%) and moderate alcohol-drinking rate (29.3%), but low obesity rate (2.6%). They have a low calorie intake from fat (16.2% of total calorie intake) and protein (16.4%), high calorie intake from carbohydrates (67.4%), and high intake of soy food, cruciferous vegetables and fish (156.5, 110.6 and 51.7 g/day, respectively). With its unique exposure pattern and wealth of data and biological samples, the SMHS is well positioned for long-term research into NCD aetiology and prognosis. Information about accessing the SMHS resources can be found at: http://www.mc.vanderbilt.edu/swhs-smhs/.

Food safety in Thailand 1: it is safe to eat watermelon and durian in Thailand

OBJECTIVES

The wide use of pesticides raises serious concerns regarding food safety and environmental impacts. There is increasing public concern about the potential health risks linked with exposure to pesticides. Regulation of maximum residue limits (MRL) of pesticide residues in food commodities has been established in many developed countries. For developing countries, like Thailand, this regulation often exists in law, but is not completely enforced in practice. Thus, pesticide residue levels in vegetables and fruits have not been thoroughly monitored. The present study aimed to examine potential health risks associated with pesticide exposure by determining the pesticide residues in two commonly consumed fruits, watermelon and durian.

METHODS

The fruit samples were purchased from markets in central provinces of Thailand and assayed for the content of 28 pesticides. Analysis of pesticides was performed by multiresidue extraction and followed by GC-MS/MS detection.

RESULTS

Of 28 pesticides investigated, 5 were detected in 90.7% of the watermelon samples (n = 75) and 3 in 90% of durian samples (n = 30). Carbofuran, chlorpyrifos, diazinon, dimethoate and metalaxyl were found in watermelons, whereas dichlorvos, dimethoate and metalaxyl were detected in durians. However, their levels were much lower than the recommended MRL values.

CONCLUSIONS

These pesticide levels detected in the fruits are unlikely to harm the consumers; therefore it is safe to eat watermelon and durian in Thailand. While our results found negligible risk associated with pesticide exposure from consuming these common tropical fruits, special precautions should be considered to decrease total exposure to these harmful pesticides from various foods.

Nutritional epidemiology--there's life in the old dog yet!

Consideration is given to the idea that the nutritional epidemiology of cancer is dead, as some in the media have claimed. The basis for the claim does not lie in science nor has anyone with relevant knowledge made such a statement-although that, too, has been claimed. Evidence is adduced for the importance of past achievements of nutritional epidemiology. Attention is similarly drawn to recent contributions. In particular, I note the state of play of cancer and plant foods, fat and breast cancer, meat and cancer, vegetarians, intervention studies, migrant studies, and westernization of diet and lifestyle. Some next steps and some currently important questions are outlined.

Association between vitamin C intake and lung cancer: a dose-response meta-analysis

Epidemiological studies evaluating the association between the intake of vitamin C and lung cancer risk have produced inconsistent results. We conducted a meta-analysis to assess the association between them. Pertinent studies were identified by a search of PubMed, Web of Knowledge and Wan Fang Med Online through December of 2013. Random-effect model was used to combine the data for analysis. Publication bias was estimated using Begg's funnel plot and Egger's regression asymmetry test. Eighteen articles reporting 21 studies involving 8938 lung cancer cases were included in this meta-analysis. Pooled results suggested that highest vitamin C intake level versus lowest level was significantly associated with the risk of lung cancer [summary relative risk (RR) = 0.829, 95%CI = 0.734–0.937, I² = 57.8%], especially in the United States and in prospective studies. A linear dose-response relationship was found, with the risk of lung cancer decreasing by 7% for every 100 mg/day increase in the intake of vitamin C [summary RR = 0.93, 95%CI = 0.88–0.98]. No publication bias was found. Our analysis suggested that the higher intake of vitamin C might have a protective effect against lung cancer, especially in the United States, although this conclusion needs to be confirmed.

Association between folate intake and the risk of lung cancer: a dose-response meta-analysis of prospective studies

Background

Studies have reported inconsistent results regarding the existence of an association between folate intake and the risk of lung cancer. The purpose of this study was to summarize the evidence from prospective cohort studies regarding this relationship by using a dose-response meta-analytic approach.

Methodology and Principal Findings

In September 2013, we performed electronic searches in PubMed, Embase, and the Cochrane Library to identify studies examining the effect of folate intake on the incidence of lung cancer. Only prospective cohort studies that reported the effect estimates about the incidence of lung cancer with 95% confidence intervals (CIs) for more than 2 categories of folate intake were included. Overall, we examined 9 cohort studies reporting the data of 566,921 individuals. High folate intake had little effect on the risk of lung cancer (risk ratio [RR], 0.92; 95% CI, 0.84–1.01; P = 0.076). Dose-response meta-analysis also suggested that a 100 µg/day increase in folate intake had no significant effect on the risk of lung cancer (RR, 0.99; 95% CI, 0.97–1.01; P = 0.318). Subgroup analysis suggested that the potential protective effect of low folate intake (100–299 µg/day) was more evident in women than men, while the opposite was true of high folate intake (>400 µg/day). Finally, subgroup analyses of a 100 µg/day increment in folate intake indicated that its potential protective effect was more evident in men than in women.

Conclusion/Significance

Our study revealed that folate intake had little or no effect on the risk of lung cancer. Subgroup analyses indicated that an increased folate intake was associated with a reduced risk of lung cancer in men. Furthermore, low folate intake may be a protective factor for women, and high folate intake for men.

β,β-carotene 15,15'-monooxygenase and its substrate β-carotene modulate migration and invasion in colorectal carcinoma cells

BACKGROUND

β,β-Carotene 15,15'-monooxygenase (BCMO1) converts β-carotene to retinaldehyde. Increased β-carotene consumption is linked to antitumor effects. Retinoic acid reduces the invasiveness in cancer, through inhibition of matrix metalloproteinases (MMPs). In our studies of a mouse model that develops intestinal tumors after low dietary folate, we found reduced BCMO1 expression in normal preneoplastic intestine of folate-deficient tumor-prone mice.

OBJECTIVE

Our goal was to determine whether BCMO1 expression could influence transformation potential in human colorectal carcinoma cells, by examining the effect of BCMO1 modulation on cellular migration and invasion, and on expression of MMPs.

DESIGN

LoVo colon carcinoma cells were transfected with BCMO1 small interfering RNA (siRNA) or scrambled siRNA. Migration and invasion were measured, and the expression of BCMO1, MMP7, and MMP28 was assessed by quantitative reverse-transcriptase polymerase chain reaction. These variables were also measured after treatment of cells with retinoic acid, 5-aza-2'-deoxycytidine, folate-depleted/high-methionine medium, and β-carotene.

RESULTS

Retinoic acid decreased the migration, invasion, and expression of MMP28 mRNA. Transfection of cells with BCMO1 siRNA inhibited BCMO1 expression, enhanced migration and invasion, and increased expression of MMP7 and MMP28. 5-Aza-2'-deoxycytidine decreased, whereas folate-depleted/high-methionine medium increased invasiveness. β-Carotene increased BCMO1 expression and reduced invasiveness with a decrease in expression of MMP7 and MMP28.

CONCLUSIONS

Inhibition of BCMO1 expression is associated with increased invasiveness of colon cancer cells and increased expression of MMP7 and MMP28. β-Carotene can upregulate BCMO1 and reverse these effects. These novel associations suggest a critical role for BCMO1 in cancer and provide a mechanism for the proposed antitumor effects of β-carotene.