flavan-3-ol and Lung-Neoplasms

It has been hypothesized that flavonoids in foods and beverages may reduce cancer risk through antioxidation, inhibition of inflammation, and other antimutagenic and antiproliferative properties. We examined associations between intake of 5 flavonoid subclasses (anthocyanidins, flavan-3-ols, flavones, flavonols, and flavanones) and lung cancer risk in a population-based case-control study in Montreal, Canada (1061 cases and 1425 controls). Flavonoid intake was estimated from a food frequency questionnaire that assessed diet 2 yr prior to diagnosis (cases) or interview (controls). Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression. Overall, total flavonoid intake was not associated with lung cancer risk, the effect being similar regardless of sex and smoking level. However, low flavonoid intake from food, but not from beverages, was associated with an increased risk. The adjusted ORs (95% CIs) comparing the highest vs. the lowest quartiles of intake were 0.63 (0.47-0.85) for total flavonoids, 0.82 (0.61-1.11) for anthocyanidins, 0.67 (0.50-0.90) for flavan-3-ols, 0.68 (0.50-0.93) for flavones, 0.62 (0.45-0.84) for flavonols, and 0.70 (0.53-0.94) for flavanones. An inverse association with total flavone and flavanone intake was observed for squamous cell carcinoma but not adenocarcinoma. In conclusion, low flavonoid intake from food may increase lung cancer risk.

Topics: Adenocarcinoma; Adult; Aged; Anthocyanins; Canada; Carcinoma, Squamous Cell; Case-Control Studies; Confidence Intervals; Diet; Female; Flavanones; Flavones; Flavonoids; Humans; Life Style; Logistic Models; Lung Neoplasms; Male; Middle Aged; Multivariate Analysis; Odds Ratio; Risk Factors; Smoking; Surveys and Questionnaires

Limited amount of evidence suggests that high intake of flavonoids could be associated with decreased risk of lung and colorectal cancer, but more studies are needed. In this prospective cohort study, we assessed the relation between the intakes of 26 flavonoids from 5 subclasses; flavonols, flavones, flavanones, flavan-3-ols and anthocyanidins, and the risk of lung, prostate and colorectal cancer. The study population consisted of 2,590 middle-aged eastern Finnish men of the prospective population-based Kuopio Ischaemic Heart Disease Risk Factor (KIHD) Study. The mean intake of flavonoids was 131.0 +/- 214.7 mg/day. During the mean follow-up time of 16.2 years, 62 lung, 138 prostate, and 55 colorectal cancers occurred. All lung cancer cases occurred among either current smokers (n = 50) or previous smokers (n = 12). After adjustment for age, examination years, body mass index, smoking status, pack-years of smoking, physical activity and intakes of alcohol, total fat, saturated fat, fiber, vitamin C and E, relative risk (RR) for lung cancer was 0.27 (95% CI: 0.11-0.66) for the highest quarter of total flavonoid intake as compared with the lowest quarter. Out of 5 flavonoid subclasses, flavonols and flavan-3-ols were associated with lung cancer, for the highest quarter of intake the RR were 0.29 (95% CI: 0.11-0.78) and 0.24 (95% CI: 0.09-0.64), respectively. No association between flavonoid intake and risk of prostate or colorectal cancer were found. We conclude that high intake of flavonoids is associated with decreased risk of lung cancer in middle-aged Finnish smoking men.

Topics: Anthocyanins; Colorectal Neoplasms; Feeding Behavior; Finland; Flavanones; Flavones; Flavonoids; Flavonols; Follow-Up Studies; Humans; Incidence; Life Style; Lung Neoplasms; Male; Middle Aged; Neoplasms; Odds Ratio; Prospective Studies; Prostatic Neoplasms; Risk Assessment; Risk Factors; Smoking

Flavonoids, which are found in certain plant foods, are thought to lower cancer risk through their antioxidant, antiestrogenic and antiproliferative properties. We examined the association of intake of total flavonoids and 7 flavonoid subclasses with risk of lung, colorectal, breast, pancreatic and upper aerodigestive cancer among women in a large prospective cohort study. Study participants were 34,708 postmenopausal women in the Iowa Women's Health Study who completed a food frequency questionnaire and were followed for cancer occurrence from 1986 through 2004. Flavonoid intake was estimated from 3 databases developed by the USDA Nutrient Data Laboratory (NDL). Hazard ratios (HR) for cancer risk were calculated across total flavonoid and flavonoid subclass intake categories. Interactions between smoking history and flavonoid intake were also examined. After multivariable adjustment, lung cancer incidence was inversely associated with intakes of flavanones (HR = 0.68; 95% CI: 0.53-0.86, all results highest vs. lowest quintile) and proanthocyanidins (HR = 0.75; 95% CI: 0.57-0.97). Among current and past smokers, those with intakes in the highest quintile for flavanones (HR = 0.66; 95% CI: 0.50-0.86), and proanthocyanidins (HR = 0.66; 95% CI; 0.49-0.89) had significantly lower lung cancer incidence than those in the lowest quintile. Similar associations were not seen in never smokers. Isoflavone intake was inversely associated with overall cancer incidence (HR = 0.93, 95% CI: 0.86-1.00). This study provides further support for a beneficial effect of flavonoid intake on lung cancer risk, especially among current and past smokers.

Topics: Aged; Anthocyanins; Breast Neoplasms; Digestive System Neoplasms; Feeding Behavior; Female; Flavanones; Flavones; Flavonoids; Flavonols; Humans; Iowa; Isoflavones; Lung Neoplasms; Middle Aged; Neoplasms; Odds Ratio; Postmenopause; Proanthocyanidins; Prospective Studies; Risk Assessment; Risk Factors; Smoking; Surveys and Questionnaires

We have examined the role of three classes of flavonoids that are relatively common in the Greek diet (flavanones, flavan-3-ols, and flavonols) in the etiology of lung cancer using data from a case-control study among women, which was undertaken in Athens, Greece, in the late 1980s. Study subjects were 154 women with lung cancer and 145 control women with orthopedic conditions. Women reported their life-long smoking histories and average frequency of consumption, before onset of present disease, of 47 food items or beverages that collectively covered >80% of the intake of each of the energy-providing nutrients. Intakes of flavonoids were calculated using the recently published U.S. Department of Agriculture database. The data were modeled through logistic regression, controlling for energy intake and smoking. There was no indication that intake of any of the studied flavonoid categories reduces the risk of lung cancer; indeed, for flavonols there was an unexpected positive association. Thus, our study does not indicate a protective effect of flavanones, flavan-3-ols, or flavonols on lung cancer risk and indicates that the factors responsible for the protective effect of vegetables and fruits against the risk of this cancer are unlikely to belong to these flavonoid categories.

Topics: Case-Control Studies; Female; Flavanones; Flavonoids; Flavonols; Fruit; Greece; Humans; Logistic Models; Lung Neoplasms; Middle Aged; Risk Factors; Smoking; Vegetables