Vegetables, fruit, and cancer. II. Mechanisms

Steinmetz, Kristi A.; Potter, John D.

doi:10.1007/bf00054304

Cited by 793 publications

(380 citation statements)

References 120 publications

Supporting

Mentioning

363

Contrasting

Unclassified

Order By: Relevance

“…This association was, however, apparently not attributable to quercetin, as the intake was not associated with CVA incidence. In addition to quercetin, however, apples also include catechin and other compounds that may explain the associations (Steinmetz & Potter, 1991). Our study is thus at variance with an earlier study based on a small male population (Keli et al, 1996), which suggested the presence of a protective effect of¯avonoids stemming primarily from black tea.…”

Section: Discussioncontrasting

confidence: 84%

Quercetin intake and the incidence of cerebrovascular disease

et al. 2000

View full text Add to dashboard Cite

Objective: To study the relation between intake of the antioxidant¯avonoid quercetin and subsequent incidence of cerebrovascular disease (CVA). Design: A cohort study carried out among 9208 Finnish men and women 15 y or more of age and initially free from cardiovascular disease. During a 28 y follow-up period in 1967 ± 1994, a total of 824 cases with CVA were diagnosed. Methods: Food consumption data were collected using a dietary history interview method covering the total habitual diet during the previous year. Results: Quercetin intake was not associated with CVA incidence. The relative risk of CVA adjusted for age, serum cholesterol, body mass index, smoking, hypertension, diabetes, geographical area, occupation and intake of beta-carotene, vitamin E, vitamin C, ®bre, various fatty acids, and energy between the highest and lowest quartiles of quercetin intake was 0.99 (95% con®dence interval (CI) 0.71 ± 1.38) for men and 0.85 (CI 0.60 ± 1.21) for women. In contrast, apples, the major source of quercetin in the study population, showed a signi®cant inverse association both in men and women, mainly due to an association with thrombotic or embolic stroke. The relative risks of thrombotic stroke after further adjustment for quercetin intake were 0.59 (CI 0.35 ± 0.99; P 0.45) and 0.61 (CI 0.33 ± 1.12: P for trend 0.02) for men and women, respectively. Conclusions: The results suggest that the intake of apples is related to a decreased risk of thrombotic stroke. This association apparently is not due to the presence of the antioxidant¯avonoid quercetin.

show abstract

Section: Discussioncontrasting

confidence: 84%

Quercetin intake and the incidence of cerebrovascular disease

et al. 2000

View full text Add to dashboard Cite

show abstract

“…This may be due to the anti-carcinogenic action of other constituents, including carotenoids such as lycopene, beta-carotene and lutein, which are present in yellow-orange or dark-green leafy vegetables, or other micronutrients present in these foods. 11,21 With regard to fruit intake, the small number of smokers is likely to have affected the power of our study to detect a significant relationship; the odds ratio for the highest tertile does suggest the possibility of a substantial reduction in risk that is consistent with results for smokers in other studies. 11,13 Interestingly, recent results from a prospective investigation (the Nurses' Health Study) show a significant reduction in risk with the highest quintile of intake for total vegetables, but not fruit, among current smokers, whereas among never smokers, the highest tertile of fruit intake had a significant protective effect.…”

Section: Discussionsupporting

confidence: 67%

Diet, reproductive factors and lung cancer risk among Chinese women in Singapore: Evidence for a protective effect of soy in nonsmokers

Seow

Poh

Teh

et al. 2001

Intl Journal of Cancer

107

View full text Add to dashboard Cite

The factors associated with risk of lung cancer among nonsmokers have not been fully elucidated, but dietary factors have consistently been shown to play a role. Chinese women are unique in having a high incidence of lung cancer despite a low smoking prevalence. This population is also known to have a high intake of soy, a dietary source of phytoestrogens. We conducted a hospital-based case-control study among Singapore Chinese women, comprising 303 cases and 765 age-matched controls, of whom 176 cases and 663 controls were lifetime nonsmokers. Data on demographic background, reproductive factors and dietary intake of fruit, vegetables and soy foods were obtained by in-person interview. We observed an inverse association between intake of total, cruciferous and non-cruciferous vegetables and risk of lung cancer among smokers. Although smokers in the highest tertile of fruit intake also had a lower risk, this was not statistically significant. Higher intake of soy foods significantly reduced risk of lung cancer among lifetime nonsmokers, but not among smokers. When soy isoflavonoid intake in mg/week was computed based on frequency and portion size of intake of eight common local soy foods, the adjusted OR among nonsmokers for the highest tertile compared to the lowest was 0.56, 95% CI 0.37-0.85 (p for trend <0.01). Fruit intake was also significantly associated with reduced lung cancer risk among nonsmokers, but the effect was not significant after adjustment for soy intake. On the other hand, soy intake remained an independent predictor of risk after controlling for fruit intake. Reproductive effects were also primarily confined to lifetime nonsmokers, among whom having 3 or more livebirths (adjusted OR 0.65, 0.44 -0.96) and a menstrual cycle length of more than 30 days (OR 0.46, 0.25-0.84) accorded a significantly reduced risk of lung cancer. Place of birth was significantly associated with risk among nonsmokers (OR 2.6, 1.7-3.9 for China-born vs. local born) but not among smokers. When analysis was restricted to nonsmokers with adenocarcinomas, the dietary effects were consistent or enhanced. On stepwise regression, soy intake and cycle length emerged as the independent dietary and reproductive predictors of lung cancer risk in nonsmokers. These findings are consistent with other evidence suggesting an involvement of estrogen-related pathways in lung cancer among non-smoking women.

show abstract

“…However, apart from carcinogens our diet also contains anticarcinogenic compounds, i.e. minor non-nutritive constituents of vegetables and fruits which are correlated with decreased cancer risk (6,25,26). From animal studies it has been suggested that these compounds may, at least in part, be effective by virtue of enhancing detoxification systems (6,7,22,26).…”

Section: Discussionmentioning

confidence: 99%

Effects of consumption of Brussels sprouts on intestinal and lymphocytic glutathione S-transferases in humans

et al. 1995

View full text Add to dashboard Cite

A high intake of glucosinolate-containing cruciferous vege tables, such as Brussels sprouts (Brassica oleraceae), has been linked to a decreased cancer risk, but the underlying mechanism is still unclear. The aim of this study was to reveal possible modulating effects of consumption of Brussels sprouts on duodenal, rectal and lymphocytic (i) glutathione S-transferase (GST) enzyme activity, (ii) GST isozyme levels and (iii) glutathione (GSH) content. Ten healthy non-smoking volunteers were randomly assigned to two groups in a cross-over design. Five persons started on a glucosinolate-free diet (control period), while the other five consumed 300 g/day cooked Brussels sprouts, at the expense of 300 g glucosinolate-free vegetables (sprouts period). After 7 days the regimen was changed for a further week. At the end of both periods blood samples and duodenal and rectal biopsies were taken. Mean GST activity showed marked differences between duodenal, rectal and lymphocytic cytosols (737 ± 54, 321 ± 29 and 154 ± 14 nmol/min/mg protein respectively), but was uninfluenced by the dietary regimen. Isozyme distribution varied greatly between the tissues. In duodenum GST-a, -7C and -[i iso zymes were expressed in considerable amounts (8441 ± 1365,3002 ± 223 and 536 ± 248 ng/mg protein respectively). Rectal biopsies also contained above three GST classes, but here GST-n was the most pronounced expressed isozyme (2849 ± 246) followed by GST-|n (495 ± 242), while GSTa was only present in minor quantities (149 ± 31). In lymphocytes only GST-71; (755 ± 96) and GST-p, (83 ± 54) could be detected. As a result of the dietary regimen rectal GST-a and -71 levels were slightly increased at the end of the sprouts period, by 30 and 15% respectively. GSH contents were uninfluenced by the dietary regimen. In conclusion, consumption of glucosinolate-containing Brussels sprouts for 1 week results in increased rectal GST-a and -tc isozyme levels. We hypothesize that these enhanced detoxification enzyme levels may partly explain the epidemiological association between a high intake of glucosinolates (cruciferous vegetables) and a decreased risk of colorectal cancer.

show abstract

Vegetables, fruit, and cancer. II. Mechanisms

Cited by 793 publications

References 120 publications

Quercetin intake and the incidence of cerebrovascular disease

Quercetin intake and the incidence of cerebrovascular disease

Diet, reproductive factors and lung cancer risk among Chinese women in Singapore: Evidence for a protective effect of soy in nonsmokers

Effects of consumption of Brussels sprouts on intestinal and lymphocytic glutathione S-transferases in humans

Contact Info

Product

Resources

About