Carotenoid intake, vegetables, and the risk of lung cancer among white men in New Jersey

A population-based incident case-control study of lung cancer in white males was conducted during 1980-1981 in six high-risk areas in New Jersey. Interviews were completed for 763 cases and 900 controls. To assess whether dietary intake of carotenoids, preformed retinol, or total vitamin A influences the risk of lung cancer, the authors asked the respondents about the usual frequency of consumption, approximately four years earlier, of 44 food items which provide 83% of the vitamin A in the US diet and about the use of vitamin supplements. The men in the lowest quartile of carotenoid intake had a relative risk of 1.3 compared with those in the highest quartile after adjusting for smoking. No increase in risk was associated with low consumption of retinol or total vitamin A. Intake of vegetables, dark green vegetables, and dark yellow-orange vegetables showed stronger associations than did the carotenoid index; the smoking-adjusted risks of those in the lowest quartiles of consumption of these food groups reached relative risks of 1.4-1.5 compared with the risks of those in the highest quartiles. The protective effect of vegetables was limited to current and recent cigarette smokers; the smoking-adjusted relative risks for low consumers reached 1.7, 1.8, and 2.2 compared with the risks for high consumers for vegetables, dark green vegetables, and dark yellow-orange vegetables, respectively. The reduction in risk with vegetable intake was most apparent for squamous cell carcinomas, but it extended to adenocarcinomas and most other cell types when only current and recent smokers were analyzed. This protection among current and recent smokers is consistent with the model that vegetable intake prevents a late-stage event of carcinogenesis. Consumption of dark yellow-orange vegetables was consistently more predictive of reduced risk than consumption of any other food group or the total carotenoid index, possibly because of the high content of beta-carotene relative to other carotenoids in this particular food group.     

Food groups associated with a composite measure of probability of adequate intake of 11 micronutrients in the diets of women in urban Mali

The prevalence of micronutrient deficiency is high among women of reproductive age living in urban Mali. Despite this, there are little data on the dietary intake of micronutrients among women of reproductive age in Mali. This research tested the relationship between the quantity of intake of 21 possible food groups and estimated usual micronutrient (folate, vitamin B-12, calcium, riboflavin, niacin, vitamin A, iron, thiamin, vitamin B-6, vitamin C, and zinc) intakes and a composite measure of adequacy of 11 micronutrients [mean probability of adequacy (MPA)] based on the individual probability of adequacy (PA) for the 11 micronutrients. Food group and micronutrient intakes were calculated from 24-h recall data in an urban sample of Malian women. PA was lowest for folate, vitamin B-12, calcium, and riboflavin. The overall MPA for the composite measure of 11 micronutrients was 0.47 ± 0.18. Grams of intake from the nuts/seeds, milk/yogurt, vitamin A-rich dark green leafy vegetables (DGLV), and vitamin C-rich vegetables food groups were correlated (Spearman's rho = 0.20-0.36; P < 0.05) with MPA. Women in the highest consumption groups of nuts/seeds and DGLV had 5- and 6-fold greater odds of an MPA > 0.5, respectively. These findings can be used to further the development of indicators of dietary diversity and to improve micronutrient intakes of women of reproductive age.     

A case-control study of nutrient status and invasive cervical cancer. I. Dietary indicators.

A study of 748 cases and 1,411 hospital and community controls in four Latin American countries evaluated the association between certain elements of diet and invasive cervical cancer. Subjects were interviewed about their adult consumption of 58 food items, including the major sources of putative protective agents (vitamin A, carotenoids, vitamin C, and folacin) as well as other behavioral and medical characteristics related to cervical cancer. Participation rates were above 95% for both cases and controls. After adjustment for age, study site, sexual and reproductive behavior, socioeconomic status, screening practices, and detection of human papillomavirus 16/18 by filter in situ hybridization, a slightly lower risk was observed for the highest quartiles of consumption of fruit and fruit juices, while no reductions in risk were associated with vegetables, foods of animal origin, complex carbohydrates, legumes, or folacin-rich foods. When nutrient indices were derived, significant trends of decreasing risk were observed for vitamin C (adjusted odds ratio (OR) = 0.69 for the highest vs. the lowest quartile; p for trend = 0.003), beta-carotene (OR = 0.68; p = 0.02), and other carotenoids (OR = 0.61; p = 0.003). Inclusion of vitamin C and beta-carotene in the same model attenuated the association with beta-carotene, while the association with vitamin C remained unchanged. The results are consistent with those of other investigations and provide support for a protective effect of vitamin C, carotenoids, and other substances found in the same fruits and vegetables against the development of invasive cervical cancer. However, the fact that the associations were driven by relation in two of the study sites and among women of higher socioeconomic status leaves open the possibility of selection bias or effects of unidentified aspects of dietary patterns.     

Dietary micronutrients and cervical dysplasia in southwestern American Indian women.

American Indian women in the Southwest have high rates of cervical cancer and cervical dysplasia in contrast to low rates of cancers for other sites. Despite their high rates of cervical disease, no published information has specifically examined risk factors for cervical cancer or cervical dysplasia among American Indian women. We carried out a pilot case-control study of cervical dysplasia in southwestern American Indian women to examine the relationship of dietary intake of vitamin C, folacin, vitamin E, carotenoids, and retinol with cervical cytological abnormalities. Twenty-four-hour dietary recalls were collected from women with cervical dysplasia (n = 42) and women with normal cervical cytologies (n = 58). Macro- and micronutrient intake was estimated from these recalls utilizing food and nutrient data from the USDA Survey Nutrient Database. Although mean differences between cases and controls were not statistically significant for any of the micronutrients examined, women with low intake of vitamin C, folacin, and vitamin E were at increased risk of having cervical dysplasia when the data were analyzed as stratified for level of intake (low vs. high intake odds ratios were 3.0 for vitamin C, 3.3 for folacin, and 1.7 for vitamin E). The relationship between dietary micronutrients and cervical dysplasia among American Indian women warrants further investigation using more refined measures of dietary micronutrient intake, together with consideration of other risk factors for cervical disease.     

Vegetables,but Not Pickled Vegetables,Are Negatively Associated With the Risk of Breast Cancer

This study investigated the association between pickled vegetable consumption and the risk of breast cancer using a validated food frequency questionnaire. A total of 358 patients with breast cancer who were matched to 360 healthy controls by age (using a 5-yr age distribution) were recruited from the National Cancer Center in South Korea. After adjusting for nondietary risk factors, total vegetable intake was inversely associated with risk of breast cancer. However, unlike nonpickled vegetables, pickled vegetable intake and its proportion relative to total vegetables were positively associated with the risk of breast cancer, and this association was more profound and consistent when pickled vegetable intake was considered as a proportion relative to total vegetables (odds ratio [OR] = 6.24, 95% confidence interval [CI] = 3.55–10.97; P for trend <0.001 for highest vs. lowest quartiles of intake) than as the absolute consumed amount (OR = 2.47, 95% CI = 1.45–4.21; P for trend = 0.015 for highest vs. lowest quartiles of intake). These results suggest that not only the amount of total vegetable intake but also the amounts of different types of vegetable (i.e., pickled or nonpickled) and their proportions relative to total vegetables are significantly associated with the risk of breast cancer.     

Plasma carotenoid levels in Dutch men and women, and the relation with vegetable and fruit consumption

OBJECTIVE: Fruit and vegetable intake is inversely associated with cancer risk in many epidemiological studies. Accurate assessment of consumption of these foods is difficult, and biomarkers of intake would overcome several drawbacks of currently used dietary assessment methods. Therefore, we investigated the relation between plasma carotenoids and usual vegetable and fruit intake. DESIGN: Plasma carotenoid concentrations were measured and vegetable, fruit and juice consumption was assessed by a food frequency questionnaire (FFQ) in a random sample of 591 Dutch men and women aged 20-59 y from the MORGEN-project, one of the contributions to the European Prospective Investigation into Cancer and Nutrition (EPIC)-study. RESULTS: In this sample of the general Dutch population, in both genders, relative to the other carotenoids, plasma beta-cryptoxanthin was the best indicator for fruit intake, and for the sum of vegetable, fruit and juice intake, while lutein concentrations best reflected intake of vegetables, although quartiles of intake were not consistently separated. Since levels of lycopene were not associated with any of the main food groups examined, associations with total carotenoids improved when excluding lycopene, and monotonously increasing plasma levels were seen for intakes of vegetables, of fruits, and of the sum of vegetables, fruits and juices. Several vegetable types and orange/grapefruit juice were associated with plasma levels of one of the carotenoids. CONCLUSION: Plasma carotenoids were only crude indicators of vegetable and fruit intake as assessed by a FFQ; beta-cryptoxanthin for fruit intake and lutein for vegetable intake. None of the plasma carotenoids could distinguish all four quartiles of vegetables, fruit and/or juice intake.     

Diet and lung cancer risk: findings from the Western New York Diet Study

This study compares the diets of 450 lung cancer cases (296 males, 154 females) with those of 902 controls (587 males, 315 females). Cases were lung cancer patients diagnosed between August 1980 and July 1984 in three western New York counties, while controls were selected from the general population of these same counties. Usual diet was estimated by detailed interviews using a modified food frequency method. Case-control comparisons were made for dietary fat, protein, fiber, calories, cholesterol, and vitamins A, C, and E according to quartiles of intake, adjusting for age and pack-years of cigarettes by multiple logistic regression. Risk was lower for males in the lowest quartile of total dietary fat intake compared with those in the highest quartile (relative risk = 0.5), although the overall trend in the association with dietary fat was not statistically significant (p = 0.12). Likewise, there was a weak, but not statistically significant, direct association between dietary cholesterol and lung cancer in men (p = 0.17). The intake of vitamin A from fruits and vegetables (carotene) was much more strongly associated with reduced cancer risk. For males, the relative risks by quartiles (lowest intake to highest intake) were 1.8, 1.8, 1.0, 1.0 (p for trend = 0.001). For females, this relation was considerably weaker, and was not statistically significant. These findings are generally in agreement with those of several previous studies. The risk reduction associated with vitamin A from fruits and vegetables (carotene) was most evident for males, for those with squamous cell cancers, for light or ex-smokers, and for those over 60 years of age.     

High dietary iron and copper and risk of colorectal cancer: a case-control study in Burgundy, France

Several hypotheses have been proposed for colorectal carcinogenesis, including formation of free radicals. A case-control study compared nutrient intake in 171 colorectal cancer cases versus 309 general population controls, using a detailed face-to-face food history questionnaire. A food composition table enabled us to determine the mean composition of the diet in macro- and micronutrients. Dietary intakes were separately categorized into quartiles by gender. Logistic regression models were adjusted for age, sex, energy, exercise, and body mass index. High energy, copper, iron, and vitamin E intakes were associated with an overall increased risk of colorectal cancer. The odds ratios associated with the fourth quartile of intake were 2.3 (95% confidence interval, 1.3-4.0), 2.4 (1.3-4.6), 2.2 (1.1-4.7), and 1.8 (1.0-3.4) for energy, copper, iron, and vitamin E, respectively. There were no significant associations with dietary fiber, folate, calcium, or antioxidant vitamins other than vitamin E. These findings regarding iron and copper suggest that free radicals play an important role in colorectal carcinogenesis, while the findings regarding vitamin E are so far unexplained.     

Intake of Vitamin E and C in Women of Reproductive Age: Results from the Latin American Study of Nutrition and Health (ELANS)

Vitamin E was identified as a lipophilic compound essential to maintain rat pregnancy. Low vitamin E intake during early pregnancy associates with congenital malformations and embryonic loss in animals and with miscarriage and intrauterine growth restriction in humans. Vitamin E protects cell membranes from lipoperoxidation and exerts non-antioxidant activities. Its function can be restored by vitamin C; thus, intake and circulating levels of both micronutrients are frequently analyzed together. Although substantial vitamin E inadequacy was reported worldwide, its consumption in Latin America (LatAm) is mostly unknown. Using data from the Latin American Study of Nutrition and Health (Estudio Latinoamericano de Nutrición y Salud, ELANS), we evaluated vitamin E and C intake in women of reproductive age (WRA) from eight LatAm countries and identified their main food sources. Two non-consecutive 24-h dietary recalls in 3704 women aged from 15 to 49 years and living in urban locations showed low average intake of vitamin E (7.9 mg/day vs. estimated average requirement (EAR) of 12 mg/day) and adequate overall vitamin C consumption (95.5 mg/day vs. EAR of 60 mg/day). The mean regional inadequacy was 89.6% for vitamin E and 36.3% for vitamin C. The primary food sources of vitamin E were fats and oils, as well as vegetables. Vitamin C intake was explained mainly by the consumption of fruit juices, fruits, and vegetables. Combined deficient intake of both vitamins was observed in 33.7% of LatAm women. Although the implications of low antioxidant vitamins’ consumption in WRA are still unclear, the combined deficient intake of both vitamins observed in one-third of ELANS participants underscores the need for further research on this topic.     

Seeking optimal means to address micronutrient deficiencies in food supplements: A case study from the Bangladesh Integrated Nutrition Project

In seeking to improve the micronutrient contents of a food supplement used in a major community-based nutrition project in Bangladesh, operations research was conducted to compare the provision of needed micronutrients through additional food sources (fresh or dried fruits or vegetables), a micronutrient multi-mix, and a combination of the two. Micronutrient gaps (the difference between micronutrient requirements and actual micronutrient intake) were estimated for four groups of project beneficiaries, with target intakes defined as requirements for iron, calcium, zinc, vitamin A, vitamin C, riboflavin, niacin, and vitamin B12 recommended by the Food and Agriculture Organization/World Health Organization. Primary focus was placed on iron and vitamin A. Cost and bulk constraint analyses, based on cost of supplement, feasibility of delivery, and serving volume needed to achieve micronutrient targets, were used for comparing the supplement options. In terms of these analyses, the micronutrient multimix proved, by far, to be the most advantageous. Food options, however, are arguably desirable in that they provide dietary benefits additional to that of known micronutrients and may increase demand to boost production of domestic fruits and vegetables for the population as a whole. The study concludes that it is cost-effective to use powdered micronutrient mixes for such specific purposes as enrichment of supplementary food and food fortification, but encourages production and consumption of micronutrient-rich foods through programme messages and activities.     

Micronutrient adequacy of women's diet in urban Burkina Faso is low

In developing countries, urban populations are deemed to have better access to a wider variety of foods than their rural counterparts. Yet, data on micronutrient status are scarce and the impact of urban food consumption behaviors on micronutrient adequacy is not well known. The objective of this study was to assess individual micronutrient adequacy of the diet along with food consumption behaviors of women of reproductive age in Ouagadougou, Burkina Faso. A cross-sectional survey of 182 women was conducted in 2 districts of the city. Nutrient intakes were derived from 3 nonconsecutive quantitative 24-h recalls for each woman. Balance in macronutrients was in the range of recommendations except that mean sugar intake was somewhat high. Mean probability of adequacy across 11 micronutrients was low (0.38). The most problematic micronutrients were vitamin B-12 (only 4% of our sample had sufficient intake), folate (12%), riboflavin (13%), and niacin (20%). Higher intakes of organ meat, flesh foods, vitamin A- and vitamin C-rich fruits and vegetables, and legumes and nuts were significantly associated with lower risk of micronutrient inadequacy. Ready-to-eat foods bought outside the home provided 46% of overall energy intake, 52% of fat intake, and 72% of sugar intake but were not associated with micronutrient inadequacy (P > 0.05). These results highlight the low micronutrient intakes among women of reproductive age in Burkina Faso, even in an urban area.     

Vegetable and fruit consumption in relation to prostate cancer risk in Hawaii: a reevaluation of the effect of dietary beta-carotene

This is a further analysis of a case-control study of 452 prostate cancer cases and 899 population controls that was conducted in 1970-1983 among the multiethnic population of Hawaii. Because a previous analysis had shown a positive association with intake of beta-carotene, a nutrient presently being tested for chemoprevention, the authors reexamined the data for consistency among the main food sources of beta-carotene. Vegetables and fruits containing other phytochemicals suspected to be cancer inhibitors were also examined. With the exception of papaya, which was positively associated with risk among men aged 70 years and older, consumption of other yellow-orange fruits and vegetables, tomatoes, dark green vegetables, and cruciferous vegetables was not associated with prostate cancer risk. These results suggest that: 1) the positive association with beta-carotene intake among older men that the authors previously reported was essentially due to the greater papaya consumption of cases compared with controls; and 2) intake of beta-carotene, lycopene, lutein, indoles, phenols, or other phytochemicals is not associated with prostate cancer risk.     

Fruits and Vegetables in Relation to Prostate Cancer in Japanese Men: The Japan Public Health Center-Based Prospective Study

Although dietary risk factors may differ between localized and advanced prostate cancer, data on associations between the consumption of fruits and vegetables and risk of localized and advanced cancers are limited. We examined associations between fruit and vegetable consumption and risk of prostate cancer in a Japanese population. During 1995–1998, a validated food frequency questionnaire was administered to 43,475 men aged 45–74 yr. During 321,061 person-years of follow-up until the end of 2004, 339 cases of prostate cancer were identified. Consumption of fruits or total vegetables was not associated with a decreased risk of total prostate cancer, with corresponding multivariate hazard ratios of the highest vs. lowest quartiles of 1.09 (95% CI = 0.77–1.53; trend P = 0.39) for fruits and 1.33 (95% CI = 0.93–1.91; trend P = 0.52) for total vegetables. Also, no association was observed for intake of either fruits or vegetables (total or any subtype) with localized or advanced prostate cancer. This prospective cohort study suggests that consumption of fruits or vegetables may not be associated with the risk of either localized or advanced prostate cancer in Japanese men. However, the possibility of confounding by detection bias on the risk of localized cancer could not be totally ruled out.     

Fruit and vegetable intake and risk of total cancer and cardiovascular disease: Japan Public Health Center-Based Prospective Study

Few studies have investigated the effects of fruit and vegetables on the risk of both cancer and cardiovascular disease (CVD). The authors examined associations between fruit and vegetable consumption and risk of total cancer and CVD in the same Japanese population. During 1995-1998, a validated food frequency questionnaire was administered in nine areas to 77,891 men and women aged 45-74 years. During as many as 459,320 person-years of follow-up until the end of 2002, 3,230 cancer cases and 1,386 CVD cases were identified. Higher consumption of fruit, but not vegetables, was associated with significantly lower risk of CVD: multivariate hazard ratios for the highest versus lowest quartiles of intake were 0.81 (95% confidence interval (CI): 0.67, 0.97; trend p = 0.01) for fruit and 0.97 (95% CI: 0.82, 1.15; trend p = 0.66) for vegetables. Consumption of fruit or vegetables was not associated with decreased risk of total cancer: corresponding hazard ratios were 1.02 (95% CI: 0.90, 1.14; trend p = 0.95) for fruit and 0.94 (95% CI: 0.84, 1.05; trend p = 0.16) for vegetables. This prospective cohort study demonstrated that, in the Japanese population, consumption of fruit is associated with lower risk of CVD, whereas fruit or vegetables may not be associated with lower risk of total cancer.     

Vegetable intake and pancreatic cancer risk: the multiethnic cohort study

Investigators studying associations between vegetable intake and pancreatic cancer risk have reported inconsistent findings to date. To further explore these associations, the authors analyzed data on 183,522 participants enrolled in the Hawaii-Los Angeles Multiethnic Cohort Study in 1993-1996. Intakes of total vegetables, light green, dark green, yellow-orange, and cruciferous vegetables, tomato products, and legumes were estimated from a quantitative food frequency questionnaire. After an average of 8.3 years of follow-up, 529 pancreatic cancer cases were identified. Multivariate-adjusted Cox proportional hazards models were created. All statistical tests were two-sided. Overall, total vegetable intake was not associated with pancreatic cancer risk, nor was intake of vegetable subgroups. Current smokers, who were at increased risk of pancreatic cancer (relative risk = 1.78, 95% confidence interval: 1.40, 2.27), had a decreased risk with higher intake of dark green vegetables (for comparison of extreme quartiles, relative risk = 0.50, 95% confidence interval: 0.27, 0.92; p-trend = 0.029). The inverse association for dark green vegetables was also seen in African Americans (p-trend = 0.043). In stratified analyses, inverse associations with total vegetables, light green vegetables, and legumes were significant in overweight/obese subjects. In conclusion, the authors found no evidence for an inverse association between vegetable intake and pancreatic cancer overall, but inverse associations in high-risk persons suggest the need for further investigation.     

Micronutrients: dietary intake v. supplement use

Whilst clinical deficiency of micronutrients is uncommon in the developed world, a suboptimal intake of certain micronutrients has been linked with an increased risk of chronic diseases such as CVD and cancer. Attention has therefore focused on increasing micronutrient status in order to theoretically reduce chronic disease risk. Increasing micronutrient status can involve a number of approaches: increasing dietary intake of micronutrient-rich foods; food fortification; use of supplements. Observational cohort studies have demonstrated an association between high intakes of micronutrients such as vitamin E, vitamin C, folic acid and beta-carotene, and lower risk of CHD, stroke and cancer at various sites. However, randomised intervention trials of micronutrient supplements have, to date, largely failed to show an improvement in clinical end points. The discordance between data from cohort studies and the results so far available from clinical trials remains to be explained. One reason may be that the complex mixture of micronutrients found, for example, in a diet high in fruit and vegetables may be more effective than large doses of a small number of micronutrients, and therefore that intervention studies that use single micronutrient supplements are unlikely to produce a lowering of disease risk. Studies concentrating on whole foods (e.g. fruit and vegetables) or diet pattern (e.g. Mediterranean diet pattern) may be more effective in demonstrating an effect on clinical end points. The present review will consider the clinical trial evidence for a beneficial effect of micronutrient supplements on health, and review the alternative approaches to the study of dietary intake of micronutrients.     

Consumption of Foods and Micronutrients and the Risk of Cancer of the Biliary Tract

Background. Gallstones and obesity have been suggested as risk factors for cancer of the biliary tract. Since both factors are related to diet, we studied the relationship between dietary intake and the cancer of interest in a population-based case-control study. Methods. The study population comprised 111 patients and 480 controls. Food intake was assessed by means of a semiquantitative food frequency questionnaire. Estimates of the intake of foods and micronutrients were obtained from cases and controls themselves (direct respondents) or from relatives (indirect respondents). Participants were categorized into tertiles of intake. Risk ratios were estimated by logistic regression analysis. Results. The major findings are a monotonic decrease in risk associated with the consumption of vegetables (ORs 1.0, 0.7, 0.4; P value trend <0.01) and a monotonic increase in risk associated with sugar added to drinks and desserts (ORs 1.0, 1.3, 2.5; P value trend <0.01). Conclusions. The finding on added sugar corresponds to our earlier report that the group monosaccharides and disaccharides is a potential risk factor for this cancer. Sugar may influence bile composition through lipoprotein metabolism. The protective effect of vegetables is in accordance with the reported inverse relationship between vegetables and many epithelial cancers of the alimentary tract.     

Calcium, vitamin D, and dairy product intake and prostate cancer risk: the Multiethnic Cohort Study

High intakes of calcium and dairy products have been suggested to be related to prostate cancer risk. Such associations were examined in the Multiethnic Cohort Study (1993-2002) among 82,483 men who completed a detailed quantitative food frequency questionnaire. During a mean follow-up of 8 years, 4,404 total cases of prostate cancer were identified. In Cox proportional hazards models, no association was found between calcium and vitamin D intake and total, advanced, or high-grade prostate cancer risk, whether for total intake, intake from foods, or intake from supplements, among all male participants or among nonusers of supplemental calcium. No association of calcium or vitamin D intake was seen across racial/ethnic groups. In analyses of food groups, dairy product and total milk consumption were not associated with prostate cancer risk. However, low-/nonfat milk was related to an increased risk and whole milk to a decreased risk of total prostate cancer; after stratification, these effects were limited to localized or low-grade tumors. Although the findings from this study do not support an association between the intakes of calcium and vitamin D and prostate cancer risk, they do suggest that an association with milk consumption may vary by fat content, particularly for early forms of this cancer.     

Food and nutrient intake differences between smokers and non-smokers in the US.

Data from the Second National Health and Nutrition Examination Survey were analyzed to determine food and nutrient intake differences between current smokers (also categorized as light, moderate, and heavy smokers) and non-smokers. Smokers in several age-race-sex categories have lower intakes of vitamin C, folate, fiber, and vitamin A than non-smokers, and intake tended to decrease as cigarette consumption increased, particularly for vitamin C, fiber, and folate. Smokers were less likely to have consumed vegetables, fruits (particularly fruits and vegetables high in vitamins C and A), high fiber grains, low fat milk, and vitamin and mineral supplements than non-smokers. A negative linear trend was found between smoking intensity and intake of several categories of fruits and vegetables. These data suggest that the high cancer risk associated with smoking is compounded by somewhat lower intake of nutrients and foods which are thought to be cancer protective.     

Intakes of Vitamin A,C, and E,and β-Carotene Are Associated With Risk of Cervical Cancer: A Case-Control Study in Korea

Cervical cancer is one of the most common gynecological malignancies in Korea, although the incidence has been declining in recent years. This study explored whether antioxidant vitamin intakes influenced the risk of cervical cancer. The association between antioxidant vitamin intakes and cervical cancer risk was calculated for 144 cervical cancer cases and 288 age-matched, hospital-based controls using unconditional logistic regression models. Cases reported statistically lower mean dietary intakes of vitamin A, β -carotene, and vitamin C than did controls. Total intakes of vitamins A and E, which included both dietary and supplement intake, were also lower in cases. Those patients in the highest quartiles of dietary vitamin A, β -carotene, and vitamin C intakes had statistically significantly lower cervical cancer risks than those in the lowest quartiles for vitamin A, β -carotene, and vitamin C: odds ratio (OR) = 0.36 [95% confidence interval (CI) = 0.19–0.69), OR = 0.48 (CI = 0.26–0.88), and OR = 0.36 (CI = 0.18–0.69), respectively. Total intakes of vitamins A, C, and E were strongly inversely associated with cervical cancer risk: OR = 0.35 (CI = 0.19–0.65), OR = 0.35 (CI = 0.19–0.66), and OR = 0.53 (CI = 0.28–0.99), respectively. The findings support a role for increased antioxidant vitamin intake in decreasing the risk of cervical cancer. These associations need to be assessed in large prospective studies with long-term follow-up.