Higher intake of carotenoid is associated with a lower risk of colorectal cancer in Chinese adults: a case–control study

Purpose

The associations between specific carotenoid intake and colorectal cancer risk remain inconsistent. The aim of this study was to examine the association between specific dietary carotenoid intake with colorectal cancer risk in Chinese adults.

Method

From July 2010 to October 2013, 845 eligible colorectal cancer cases and 845 frequency-matched controls (age and sex) completed in-person interviews. A validated food frequency questionnaire was used to estimate dietary intake. Multivariate logistical regression models were used to calculate the odds ratio (OR) and 95 % confidence intervals (95 % CIs) of colorectal cancer risk after adjusting for various confounders.

Results

A strong inverse association was found between β-cryptoxanthin intake and colorectal cancer risk. Compared with the lowest quartile, the highest quartile intake showed a risk reduction of 77 % (OR 0.23, 95 % CI 0.17–0.33, P _trend < 0.01) after adjustment for various confounding variables. The inverse associations were also observed for α-carotene (OR 0.50, 95 % CI 0.37–0.68, P _trend < 0.01), β-carotene (OR 0.67, 95 % CI 0.49–0.91, P _trend < 0.01), and lycopene (OR 0.51, 95 % CI 0.37–0.70, P _trend < 0.01). There was no statistically significant association between lutein/zeaxanthin intake and colorectal cancer risk. These findings were consistent across cancer site, sources of controls, and smoking status. The inverse associations between dietary α-carotene, β-cryptoxanthin, and lycopene intake and colorectal cancer risk were found in both males and females, while inverse associations between β-carotene intake and colorectal cancer risk were only observed in males.

Conclusions

Consumption of α-carotene, β-carotene, β-cryptoxanthin, and lycopene was inversely associated with colorectal cancer risk. No significant association was found between lutein/zeaxanthin intake and colorectal cancer risk.

     

Plasma carotenoids, retinol, and tocopherols and risk of breast cancer

The roles of carotenoids, retinol, and tocopherols in breast cancer etiology have been inconclusive. The authors prospectively assessed the relations between plasma alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, lutein/zeaxanthin, retinol, alpha-tocopherol, and gamma-tocopherol and breast cancer risk by conducting a nested case-control study using plasma collected from women enrolled in the Nurses' Health Study. A total of 969 cases of breast cancer diagnosed after blood draw and prior to June 1, 1998, were individually matched to controls. The multivariate risk of breast cancer was 25-35% less for women with the highest quintile compared with that for women with the lowest quintile of alpha-carotene (odds ratio (OR) = 0.64, 95% confidence interval (CI): 0.47, 0.88; p(trend) = 0.01), beta-carotene (OR = 0.73, 95% CI: 0.53, 1.02; p(trend) = 0.01), lutein/zeaxanthin (OR = 0.74, 95% CI: 0.55, 1.01; p(trend) = 0.04), and total carotenoids (OR = 0.76, 95% CI: 0.55, 1.05; p(trend) = 0.05). The inverse association observed with alpha-carotene and breast cancer was greater for invasive cancers with nodal metastasis. The authors conclude that some carotenoids are inversely associated with breast cancer. Although the association was strongest for alpha-carotene, the high degree of collinearity among plasma carotenoids limits our ability to conclude that this association is specific to any individual carotenoid.     

Dietary Fat,Cooking Fat,and Breast Cancer Risk in a Multiethnic Population

Our objective was to examine the association between dietary fat intake, cooking fat usage, and breast cancer risk in a population-based, multiethnic, case-control study conducted in the San Francisco Bay area. Intake of total fat and types of fat were assessed with a food frequency questionnaire among 1,703 breast cancer cases diagnosed between 1995 and 1999 and 2,045 controls. In addition, preferred use of fat for cooking was assessed. Unconditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). High fat intake was associated with increased risk of breast cancer (highest vs. lowest quartile, adjusted OR = 1.35, 95% CI = 1.10–1.65, P _trend < 0.01). A positive association was found for oleic acid (OR = 1.55, 95% CI = 1.14–2.10, P _trend < 0.01) but not for linoleic acid or saturated fat. Risk was increased for women cooking with hydrogenated fats (OR = 1.58, 95% CI = 1.20–2.10) or vegetable/corn oil (rich in linoleic acid; OR = 1.30, 95% CI = 1.06–1.58) compared to women using olive/canola oil (rich in oleic acid). Our results suggest that a low-fat diet may play a role in breast cancer prevention. We speculate that monounsaturated trans fats may have driven the discrepant associations between types of fat and breast cancer.     

Intake of Vitamins D and A and Calcium and Risk of Non-Hodgkin Lymphoma: San Francisco Bay Area Population-Based Case-Control Study

Several nutrients identified as potentially cancer protective have been inconsistently associated with non-Hodgkin lymphoma (NHL) risk. Dietary history data, including use of vitamin supplements, were collected using a semiquantitative food frequency questionnaire administered during in-person interviews with 4,133 participants (2,052 cases, 2,081 controls) in a San Francisco Bay Area population-based case-control study. Data were used to determine the association of intake levels of vitamins D and A and calcium with risk of NHL and NHL subtypes. Odds ratios (OR) and 95% confidence intervals (CI) were computed as estimates of relative risk using adjusted unconditional logistic regression. Increasing vitamin D intake from food and supplements was positively associated with NHL risk in men (5th quintile: OR = 1.6, 95% CI = 1.0–2.4, P _trend = 0.07) and with diffuse large B-cell lymphoma (DLBCL) in women and men (5th quintile: OR = 1.6, 95% CI = 1.0–2.5, P _trend = 0.02); that was largely due to the effect in men (P _trend = 0.03). These results do not support a strong role for vitamin D intake with NHL risk, with the exception of a potential association for DLBCL risk in men. Our results should be interpreted conservatively until further investigation in larger pooled studies can be conducted to better assess the role of vitamin D intake in lymphomagenesis.     

The Association between Coffee Consumption and Risk of Colorectal Cancer in a Korean Population

This study was performed to investigate the association between coffee consumption and risk of colorectal cancer in a Korean population and examine whether the association can be altered by adjustment for intake of coffee additives. We conducted a case-control study involving 923 colorectal cancer cases and 1846 controls matched by sex and age (within 5 years). A semi-quantitative food frequency questionnaire was used to assess coffee intakes. High coffee consumption was associated with lower odds of developing colorectal cancer (≥3 cups/day vs. no drinks, OR = 0.68; 95% CI: 0.49–0.96). When we additionally controlled for consumption of coffee additives including sugar and cream, the inverse association became stronger (≥3 cups/day vs. no drinks, OR = 0.22; 95% CI: 0.14–0.33), and a significant inverse linear trend was shown (P_trend < 0.0001). The inverse associations were observed for proximal (P_trend = 0.0001) and distal (P_trend = 0.0003) colon cancer, and rectal cancer (P_trend < 0.0001) in the stratified analysis by anatomical sub-sites. Regarding sex, inverse associations between coffee consumption and colorectal cancer were found for men (P_trend < 0.0001) and women (P_trend = 0.0021). In the stratified analysis by obese status of subjects, inverse linear trends were observed in both non-obese and obese people (P_trend < 0.0001). High coffee consumption may be associated with a lower risk of colorectal cancer in the Korean population and the degree of decrease in the odds of developing colorectal cancer changes by adjustment for intake of coffee additives.     

Fruit, vegetables, fibre and micronutrients and risk of US renal cell carcinoma

The association between renal cell cancer (RCC) and intake of fruit, vegetables and nutrients was examined in a population-based case-control study of 323 cases and 1827 controls; dietary intake was obtained using a mailed questionnaire. Cancer risks were estimated by OR and 95?% CI, adjusting for age, sex, smoking, obesity, hypertension, proxy status, alcohol consumption and dietary fat intake and energy. Intake of vegetables was associated with a decreased risk of RCC (OR 0·5; 95?% CI 0·3, 0·7; P trend?=?0·002), (top compared to the bottom quartile of intake). When intake of individual nutrients was investigated, vegetable fibre intake was associated with decreased risks (OR 0·4; 95?% CI 0·2, 0·6; P?相似文献   

Plasma Carotenoids and Prostate Cancer: A Population-Based Case-Control Study in Arkansas

Carotenoids possess antioxidant properties and thus may protect against prostate cancer. Epidemiological studies of dietary carotenoids and this malignancy were inconsistent, partially due to dietary assessment error. In this study, we aimed to investigate the relation between plasma concentrations of carotenoids and the risk of prostate cancer in a population-based case-control study in Arkansas. Cases (n = 193) were men with prostate cancer diagnosed in 3 major hospitals, and controls (n = 197) were matched to cases by age, race, and county of residence. After adjustment for confounders, plasma levels of lycopene, lutein/zeaxanthin, and β -cryptoxanthin were inversely associated with prostate cancer risk. Subjects in the highest quartile of plasma lycopene (513.7 μ g/l) had a 55% lower risk of prostate cancer than those in the lowest quartile (140.5 μ g/l; P trend = 0.042). No apparent association was observed for plasma α -carotene and β -carotene. Further adjustment for the other 4 carotenoids did not materially alter the risk estimates for plasma lycopene, lutein/zeaxanthin, and β -cryptoxanthin but appeared to result in an elevated risk with high levels of plasma α -carotene and β -carotene. The results of all analyses did not vary substantially by age, race, and smoking status. This study added to the emerging evidence that high circulating levels of lycopene, lutein/zeaxanthin, and β -cryptoxanthin are associated with a low risk of prostate cancer.     

Association of Serum Carotenoid Levels With N-Terminal Pro-Brain-Type Natriuretic Peptide: A Cross-Sectional Study in Japan

Background

Several epidemiologic studies have reported an inverse association between serum levels of carotenoids and cardiovascular disease risk. However, no studies have reported an association between serum carotenoids and N-terminal pro-brain-type natriuretic peptide (NT-proBNP) in the general population.

Methods

In this cross-sectional study, we investigated whether serum carotenoids were associated with serum NT-proBNP in 1056 Japanese subjects (390 men, 666 women) who attended a health examination. Serum levels of carotenoids were separately determined by high-performance liquid chromatography. Serum NT-proBNP level was measured by electrochemiluminescence immunoassay.

Results

Serum NT-proBNP was elevated (≥55 pg/ml) in 31.8% of men and 48.2% of women. Multivariate logistic regression analyses adjusted for confounding factors showed a significant association between the highest quartile of serum α-carotene and elevated NT-proBNP in men (odds ratio [OR] = 0.40, 95% CI = 0.19–0.82, P for trend = 0.005) and women (OR = 0.62, 95% CI = 0.39–0.99, P for trend = 0.047). In women, moreover, elevated serum NT-proBNP was significantly associated with serum canthaxanthin (OR = 0.57, 95% CI = 0.36–0.90 for highest quartile, P for trend = 0.026) and β-cryptoxanthin (OR = 0.53, 95% CI = 0.32–0.85 for highest quartile, P for trend = 0.026), after adjusting for potential confounders.

Conclusions

Higher levels of serum carotenoids were associated with lower risk of elevated serum NT-proBNP levels after adjusting for possible confounders, which suggests that a diet rich in carotenoids could help prevent cardiac overload in the Japanese population.Key words: carotenoids, N-terminal pro-brain-type natriuretic peptide, cross-sectional study     

Dietary Iron Intake and Risk of Endometrial Cancer: A Population-Based Case-Control Study in Shanghai,China

Dietary red meat and animal fat have been linked to endometrial cancer (EC) risk, but the impact of bioavailable iron in animal-derived foods has been less well studied. Our objective was to investigate the effects of iron and fats on the risk of EC in a large, population-based, case-control study. The Shanghai Endometrial Cancer Study enrolled 1,204 EC cases and 1,212 controls who completed in-person interviews, including a food frequency questionnaire. Animal-derived iron and fat intakes were calculated from dietary intakes and food composition tables. Logistic regression models were used to evaluate independent and joint effects of iron and fat on EC risk. Animal-derived iron intake was positively associated with EC risk [adjusted OR = 1.9; 95% CI = 1.4–2.7, P _trend < 0.01, highest vs. lowest quartile], predominantly after menopause (OR = 2.2; 95%CI = 1.4–3.4, P _trend < 0.01) and in women with BMI ≥ 25 kg/m ² (OR = 3.2; 95% CI = 1.4–7.5 in postmenopausal obese women, P _trend < 0.01). Animal-derived fat was also associated with postmenopausal EC risk (OR = 1.7; 95% CI = 1.2–2.5, P _trend < 0.01). Multiplicative interactions between animal-derived iron and BMI or animal-derived fat intake were not observed. Animal-derived iron intake is associated with increased risk of EC after menopause and among obese women. Avoidance of animal-derived (heme) iron may reduce the risk of EC in these women.     

Serum β-Carotene in Relation to Risk of Prostate Cancer: The Kuopio Ischaemic Heart Disease Risk Factor Study

Results from epidemiologic studies on the association between circulating carotenoid concentrations and the risk of prostate cancer are still inconsistent. We studied whether serum concentrations of carotenoids were associated with the risk of developing prostate cancer. The study population consisted of 997 middle-aged Finnish men (56.1 ± 6.6 yr) in the Kuopio Ischaemic Heart Disease Risk Factor (KIHD) cohort. Serum concentrations of carotenoids were measured by high-performance liquid chromatography. Subjects were classified into tertiles according to their serum concentrations of antioxidants. Relative risks (RRs) were estimated by using the Cox proportional hazard models. During the mean follow-up time of 15 yr, a total of 68 prostate cancer cases occurred. After adjusting for age, examination yr, family history of cancer, BMI, pack-yr of smoking, alcohol consumption, education, physical activity, serum total cholesterol, and serum α-linolenic acid, men in the highest tertile of serum concentrations of β-carotene had 2.3-fold higher risk of prostate cancer as compared to those in the lowest tertile (RR = 2.29, 95% CI: 1.12–4.66; P = 0.023). α-Tocopherol and retinol were not associated with prostate cancer. This prospective study suggests that high-serum β-carotene concentrations may increase the risk of prostate cancer in middle-aged men.     

Dietary intake of lycopene is associated with reduced pancreatic cancer risk

Although fruits and vegetables have been implicated in the etiology of pancreatic cancer, the role of phytochemicals in these food groups has received little attention to date. In this study, we investigated the possible association between dietary carotenoids and pancreatic cancer risk. A case-control study of 462 histologically confirmed pancreatic cancer cases and 4721 population-based controls in 8 Canadian provinces took place between 1994 and 1997. Dietary intake was assessed by a self-administered FFQ. Unconditional logistic regression was used to assess associations between specific and total carotenoid intakes and the risk of pancreatic cancer. All tests of statistical significance were 2-sided. After adjustment for age, province, BMI, smoking, educational attainment, dietary folate, and total energy intake, lycopene, provided mainly by tomatoes, was associated with a 31% reduction in pancreatic cancer risk among men [odds ratio (OR) = 0.69; 95% CI: 0.46-0.96; P = 0.026 for trend] when comparing the highest and lowest quartiles of intake. Both beta-carotene (OR = 0.57; 95% CI: 0.32-0.99; P = 0.016 for trend) and total carotenoids (OR = 0.58; 95% CI: 0.34-1.00; P = 0.02 for trend) were associated with a significantly reduced risk among those who never smoked. The results of this study suggest that a diet rich in tomatoes and tomato-based products with high lycopene content may help reduce pancreatic cancer risk.     

Physical Activity,Diet, and Pancreatic Cancer: A Population-Based,Case-Control Study in Minnesota

Although mounting evidence suggests that insulin resistance is involved in pancreatic carcinogenesis, few epidemiologic studies have comprehensively investigated the role of lifestyle factors influencing this metabolic disorder in the etiology of pancreatic cancer. We sought to examine this problem in a case-control study conducted in 1994–1998 in Minnesota. Cases (n = 186), aged 20 yr or older, were ascertained from all hospitals in the metropolitan area of the Twin Cities and the Mayo Clinic; from the latter, only cases residing in the Upper Midwest of the United States were recruited. Controls (n = 554) were randomly selected from the general population and frequency matched to cases by age (within 5 yr) and sex. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using unconditional logistic regression. After adjustment for confounders, physical activity was associated with a reduced risk, but this protective effect was confined to light activity and moderate activity only (OR = 0.55, 95% CI = 0.30–0.97, P _trend = 0.038 and OR = 0.51, 95% CI = 0.28–0.93, P _trend = 0.07, for highest vs. lowest quartile, respectively). An increased risk was found for dietary intakes of energy and fat but was statistically significant for saturated and polyunsaturated fat only. Of note, no appreciable difference in the magnitude of the associations existed between saturated, monounsaturated, and polyunsaturated fat. Compared with individuals in the lowest quartile of fiber intake, the risk was approximately halved for those in the third (OR = 0.49, 95% CI = 0.26–0.94) and the highest quartile (OR = 0.52, 95% CI = 0.21–1.30). Our study lends support to the hypothesis that dietary and other lifestyle factors influencing insulin resistance modulate pancreatic cancer risk.     

Airway and Circulating Levels of Carotenoids in Asthma and Healthy Controls

Background: Elevated oxidative stress and impaired antioxidant defences are increasingly recognised features of asthma. Carotenoids are potent dietary antioxidants that may protect against asthma by reducing oxidative damage.

Objectives: This study aimed firstly, to characterise circulating and airway levels of carotenoids in asthma compared to healthy controls, in relation to dietary intake. Secondly, the study aimed to test whether airway lycopene defences can be improved using oral supplements.

Methods: Induced sputum and peripheral blood samples were collected from subjects with asthma (n = 15) and healthy controls (n = 16). Dietary carotenoid intakes were estimated using the 24-hour recall method and analysed using a modified version of the Foodworks 210 Nutrient Calculation Software. Another group of healthy controls (n = 9) were supplemented with 20 mg/day lycopene for 4 weeks. Carotenoids (β-carotene, lycopene, α-carotene, β-cryptoxanthin, lutein/zeaxanthin) were measured by HPLC.

Results: Despite similar dietary intake, whole blood levels of total carotenoids, lycopene, lutein, β-cryptoxanthin, α-carotene and β-carotene were significantly lower in asthma than controls. However, there were no differences in plasma or sputum carotenoid levels. Induced sputum carotenoid levels were significantly lower than plasma and whole blood levels, but correlated strongly with plasma levels (r = 0.798, p < 0.001). Although there were no overall increases in either plasma or sputum lycopene levels following supplementation, changes in airway lycopene levels correlated with changes in plasma levels (r = 0.908, p < 0.002).

Conclusions: Whole blood, but not plasma or sputum, carotenoid levels are deficient in asthma. Plasma carotenoid levels reflect airway carotenoid levels and when plasma levels are improved using oral supplements this is reflected in the airways.     

The relationship between total plasma carotenoids and risk factors for chronic disease among middle-aged and older men

Individual plasma carotenoids have been associated with various chronic diseases but little is known about the relationship between total plasma carotenoids and risk factors for chronic diseases. In the Physicians' Health Study, we examined 492 men free of CVD and cancer for the relationship between total plasma carotenoids (the sum of alpha-carotene, beta-carotene, lycopene, zeaxanthin, lutein and beta-cryptoxanthin) and a wide variety of factors that predict chronic disease. Multivariate linear and logistic regression was performed to calculate parameter estimates (95% CI) and OR (95% CI) for total plasma carotenoids. In linear regression models, BMI, hypertension, alcohol intake and plasma levels of each lipid parameter and a-tocopherol significantly predicted levels of total plasma carotenoids. Upon adjustment for multiple chronic disease risk factors, the OR for levels of total plasma carotenoids greater than or equal to the median (> or=1.301 micromol/l) was statistically significant for current smoking (OR 0.21; 95% CI 0.06, 0.77), weekly alcohol ingestion (OR 2.30; 95% CI 1.06, 4.99), daily alcohol ingestion (OR 2.46; 95% CI 1.29, 4.67), each 100 mg/l increase in total cholesterol (OR 0.73; 95% CI 0.58, 0.91), LDL-cholesterol (OR 1.48; 95% CI 1.17, 1.89) and HDL-cholesterol (OR 1.58; 95% CI 1.26, 1.99), each 100 mg/ml increase in intercellular adhesion molecule-1 (OR 0.70; 95% CI 0.53, 0.93) and each 10 micromol/l increase in alpha-tocopherol (OR 1.33; 95% CI 1.12, 1.57), using logistic regression. Few lifestyle and clinical risk factors appear to be related to levels of total plasma carotenoids; however, levels of biomarkers such as plasma lipids and alpha-tocopherol may be strongly related.     

Dietary Polyamines Intake and Risk of Colorectal Cancer: A Case-Control Study

Polyamines (including putrescine, spermidine, and spermine) are small, cationic molecules that are necessary for cell proliferation and differentiation. Few studies have examined the association of dietary polyamines intake with colorectal cancer risk. The aim of this study was to evaluate total polyamines, putrescine, spermidine, and spermine intake in relation to colorectal cancer risk in China. In total, 2502 colorectal cancer cases and 2538 age-(5-year interval) and sex-matched controls were recruited from July 2010 to April 2019. Odds ratios (ORs) and 95% confidence intervals (CI) were calculated by multivariable unconditional logistic regression after adjustment for various potential confounding factors. Higher intake of total polyamine, putrescine and spermidine was significantly associated with reduced risk of colorectal cancer. The adjusted ORs for the highest compared with the lowest quartile of intake were 0.60 (95% CI 0.50, 0.72; P_trend < 0.001) for total polyamines, 0.35 (95% CI 0.29, 0.43; P_trend < 0.001) for putrescine and 0.79 (95% CI 0.66, 0.95; P_trend = 0.001) for spermidine, respectively. However, higher intake of spermine was associated with increased risk of colorectal cancer, with an adjusted OR of 1.58 (95% CI 1.29, 1.93; P_trend < 0.001). This data indicate that higher intake of total polyamines, putrescine and spermidine, as well as lower intake of spermine, is associated with a decreased risk of colorectal cancer.     

A high ratio of dietary n-6/n-3 polyunsaturated fatty acids is associated with increased risk of prostate cancer

Experimental studies suggest omega-3 (n-3) polyunsaturated fatty acids (PUFA) suppress and n-6 PUFA promote prostate tumor carcinogenesis. Epidemiologic evidence remains inconclusive. The objectives of this study were to examine the association between n-3 and n-6 PUFA and prostate cancer risk and determine if these associations differ by race or disease aggressiveness. We hypothesize that high intakes of n-3 and n-6 PUFA will be associated with lower and higher prostate cancer risk, respectively. A case-control study comprising 79 prostate cancer cases and 187 controls was conducted at the Durham VA Medical Center. Diet was assessed using a food frequency questionnaire. Logistic regression analyses were used to obtain odds ratios (ORs) and 95% confidence intervals (95% CI) for the associations between n-3 and n-6 PUFA intakes, the dietary ratio of n-6/n-3 fatty acids, and prostate cancer risk. Our results showed no significant associations between specific n-3 or n-6 PUFA intakes and prostate cancer risk. The highest dietary ratio of n-6/n-3 was significantly associated with elevated risk of high-grade (OR, 3.55; 95% CI, 1.18-10.69; P_trend = 0.03), but not low-grade prostate cancer (OR, 0.95; 95% CI, 0.43-2.17). In race-specific analyses, an increasing dietary ratio of n-6/n-3 fatty acids correlated with higher prostate cancer risk among white men (P_trend = 0.05), but not black men. In conclusion, our findings suggest that a high dietary ratio of n-6/n-3 fatty acids may increase the risk of overall prostate cancer among white men and possibly increase the risk of high-grade prostate cancer among all men.     

Breast cancer and dietary and plasma concentrations of carotenoids and vitamin A

A case-control study of breast cancer was conducted in Buffalo. Participants completed a food frequency questionnaire and donated a fasting blood sample before definitive workup for breast masses. Dietary and plasma concentrations of carotenoids and retinol for 83 women found to have breast cancer were compared with those of 113 women found to be free of breast cancer (control subjects). There were no case-control differences in dietary estimates of vitamin A intake or in plasma alpha-carotene and lycopene. However, subjects with breast cancer had lower concentrations of plasma beta-carotene than did control subjects (P = 0.02). There was no overall association between plasma retinol and breast cancer but a positive relationship was observed between retinol and breast cancer in the subgroup with low beta-carotene values. These results suggest that low plasma beta-carotene is associated with increased risk of breast cancer. Other studies will need to determine whether low carotene concentrations are a subtle effect of the disease or might be causally related to breast cancer.     

Low plasma lycopene concentration is associated with increased mortality in a cohort of patients with prior oral, pharynx or larynx cancers

OBJECTIVE: This analysis was conducted to evaluate the association between plasma beta-carotene, alpha-carotene, lycopene, lutein/zeaxanthin, total carotenoids, retinol, alpha-tocopherol and subsequent mortality. METHODS: Blood samples collected longitudinally from 259 participants in a chemoprevention trial aimed at the prevention of second cancers of the oral cavity, pharynx, or larynx were analyzed by high performance liquid chromatography for selected micronutrients. All-cause mortality (primary outcome) and cause-specific mortality (secondary outcomes) were evaluated in relation to plasma micronutrient concentrations at baseline and longitudinally. RESULTS: A total of 61 deaths occurred over a follow-up time of up to 90 months. Cox proportional hazards models with time-dependent covariates were used for data analyses. In models adjusted for age, plasma cholesterol, time-dependent smoking, treatment arm, study site and gender, only plasma lycopene was significantly inversely associated with total mortality [hazard ratio (HR) above versus below median = 0.53, 95% confidence interval (CI) 0.30-0.93]. Plasma alpha-carotene was inversely associated (HR 0.24, 95% CI 0.08-0.75) while plasma retinol was positively associated (HR 5.12, 95% CI 1.54-17.05) with cardiovascular death. Smoking status modified plasma nutrient associations with total mortality. Lycopene (HR 0.08, 95% CI 0.02-0.36), alpha-carotene (HR 0.25, 95% CI 0.09-0.73) and total carotenoids (HR 0.22, 95% CI 0.07-0.70) were inversely associated with mortality in non-smokers, while plasma retinol (HR = 3.56, 95% CI 1.40-9.09) and alpha-tocopherol (HR = 2.47, 95% CI 1.02-5.98) were positively associated with mortality in smokers. CONCLUSIONS: Only plasma lycopene was significantly associated (inversely) with total mortality in the full study population. Smoking modifies associations between nutrients and mortality.     

Carotenoid intake and head and neck cancer: a pooled analysis in the International Head and Neck Cancer Epidemiology Consortium

Food and nutrition play an important role in head and neck cancer (HNC) etiology; however, the role of carotenoids remains largely undefined. We explored the relation of HNC risk with the intake of carotenoids within the International Head and Neck Cancer Epidemiology Consortium. We pooled individual-level data from 10 case–control studies conducted in Europe, North America, and Japan. The analysis included 18,207 subjects (4414 with oral and pharyngeal cancer, 1545 with laryngeal cancer, and 12,248 controls), categorized by quintiles of carotenoid intake from natural sources. Comparing the highest with the lowest quintile, the risk reduction associated with total carotenoid intake was 39 % (95 % CI 29–47 %) for oral/pharyngeal cancer and 39 % (95 % CI 24–50 %) for laryngeal cancer. Intakes of β-carotene equivalents, β-cryptoxanthin, lycopene, and lutein plus zeaxanthin were associated with at least 18 % reduction in the rate of oral and pharyngeal cancer (95 % CI 6–29 %) and 17 % reduction in the rate of laryngeal cancer (95 % CI 0–32 %). The overall protective effect of carotenoids on HNC was stronger for subjects reporting greater alcohol consumption (p < 0.05). The odds ratio for the combined effect of low carotenoid intake and high alcohol or tobacco consumption versus high carotenoid intake and low alcohol or tobacco consumption ranged from 7 (95 % CI 5–9) to 33 (95 % CI 23–49). A diet rich in carotenoids may protect against HNC. Persons with both low carotenoid intake and high tobacco or alcohol are at substantially higher risk of HNC.     

Dietary antioxidants and lung cancer risk: a case-control study in Uruguay.

To examine the protective role of dietary antioxidants (carotenoids, vitamin C, vitamin E, glutathione, and flavonoids) in lung cancer risk, a case-control study involving 541 cases of lung cancer and 540 hospitalized controls was carried out in Uruguay. The relevant variables were energy adjusted using the residuals method and then categorized in quartiles. Adjusted odds ratios (ORs) for antioxidants were calculated through unconditional logistic regression. With the exception of lycopene and vitamin C, the remaining antioxidants were associated with significant reductions in risk of lung cancer. Of particular interest was the inverse association between dietary glutathione and lung cancer [OR of quartile with highest intake compared with lowest quartile = 0.42, 95% confidence interval (CI) = 0.27-0.63]. Also, carotenoids and vitamin E were associated with significant reductions in risk of lung cancer (OR = 0.43, 95% CI = 0.29-0.64 for total carotenoids and OR = 0.50, 95% CI = 0.39-0.85 for vitamin E). A joint effect for high vs. low intakes of beta-carotene and glutathione was associated with a significant reduction in risk (OR = 0.32, 95% CI = 0.22-0.46). It could be concluded that dietary antioxidants are associated with a significant protective effect in lung carcinogenesis and that the inverse association for glutathione persisted after controlling for total vegetables and fruits.