Instruct: Given a question, retrieve relevant passages that answer the question.
Query: Breast Cancer Survival and Trans Fat
Little is known about the effects of diet after breast cancer diagnosis on survival. We prospectively examined the relation between post-diagnosis dietary factors and breast cancer and all-cause survival in women with a history of invasive breast cancer diagnosed between 1987 and 1999 (at ages 20–79 years). Diet after breast cancer diagnosis was measured using a 126-item food frequency questionnaire. Among 4,441 women without a history of breast cancer recurrence prior to completing the questionnaire, 137 subsequently died from breast cancer within 7 years of enrollment. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated for intake of macronutrients as well as selected micronutrients and food groups from Cox proportional hazards regression models. After adjustment for factors at diagnosis (age, state of residence, menopausal status, smoking, breast cancer stage, alcohol, history of hormone replacement therapy), interval between diagnosis and diet assessment, and at follow-up (energy intake, breast cancer treatment, body mass index, and physical activity), women in the highest compared to lowest quintile of intake of saturated fat and trans fat had a significantly higher risk of dying from any cause (HR = 1.41, 95% CI = 1.06 to 1.87, P-trend = 0.03) for saturated fat; (HR = 1.78, 95% CI = 1.35 to 2.32, P-trend = 0.01) for trans fat intake. Associations were similar, though did not achieve statistical significance, for breast cancer survival. This study suggests that lower intake of saturated and trans fat in the post-diagnosis diet is associated with improved survival after breast cancer diagnosis.
The role of diet in breast cancer (BC) risk is unclear. Fiber could reduce BC risk, through the enterohepatic circulation of estrogens. We examined the relationship between diet and sex hormones in postmenopausal women with or without BC. Thirty-one postmenopausal women (10 omnivores, 11 vegetarians, and 10 BC omnivores) were recruited. Dietary records (5 days) and hormone levels (3 days) were evaluated on 4 occasions over 1 yr. Vegetarians showed a lower fat/fiber ratio, a higher intake of total and cereal fiber (g/d)/body weight (kg), a significantly lower level of plasma estrone-sulfate, estradiol, free-estradiol, free-testosterone, and ring D oxygenated estrogens, and a significantly higher level of sex-hormone-binding-globulin than BC subjects. Fiber was consumed in slightly larger amounts by omnivores than by BC subjects. Omnivores had significantly lower plasma testosterone and estrone-sulfate but higher sex-hormone-binding-globulin than BC subjects. No difference was found for the urinary 16-oxygenated estrogens. However, the 2-MeO-E1/2-OH-E1 ratio was significantly lower in omnivores than in BC group. This ratio is positively associated with the fat/fiber ratio. In conclusion, testosterone may contribute to causing alterations in the levels of catechol estrogens and 16-oxygenated estrogens. The fat/fiber ratio appears to be useful in evaluating dietary effects on estrogen metabolism.
Epidemiological evidence suggests that the Mediterranean diet (MD) could reduce the risk of breast cancer (BC). As evidence from the prospective studies remains scarce and conflicting, we investigated the association between adherence to the MD and risk of BC among 335,062 women recruited from 1992 to 2000, in ten European countries, and followed for 11 years on average. Adherence to the MD was estimated through an adapted relative Mediterranean diet (arMED) score excluding alcohol. Cox proportional hazards regression models were used while adjusting for BC risk factors. A total of 9,009 postmenopausal and 1,216 premenopausal first primary incident invasive BC were identified (5,862 estrogen or progesterone receptor positive [ER+/PR+] and 1,018 estrogen and progesterone receptor negative [ER-/PR-]). The arMED was inversely associated with the risk of BC overall and in postmenopausal women (high vs. low arMED score; hazard ratio [HR] = 0.94 [95% confidence interval [CI]: 0.88, 1.00] ptrend = 0.048, and HR = 0.93 [95% CI: 0.87, 0.99] ptrend = 0.037, respectively). The association was more pronounced in ER-/PR- tumors (HR = 0.80 [95% CI: 0.65, 0.99] ptrend = 0.043). The arMED score was not associated with BC in premenopausal women. Our findings show that adherence to a MD excluding alcohol was related to a modest reduced risk of BC in postmenopausal women, and this association was stronger in receptor-negative tumors. The results support the potential scope for BC prevention through dietary modification. Copyright © 2012 UICC.
DietCompLyf is a multi-centre prospective study designed to investigate associations between phytoestrogens - naturally occurring plant compounds with oestrogenic properties - and other diet and lifestyle factors with breast cancer recurrence and survival. 3159 women with grades I-III breast cancer were recruited 9-15 months post-diagnosis from 56 UK hospitals. Detailed information on clinico-pathological, diet, lifestyle and quality of life is collected annually up to 5 years. Biological samples have also been collected as a resource for subsequent evaluation. The characteristics of the patients and associations between pre-diagnosis intake of phytoestrogens (isoflavones and lignans; assessed using the EPIC-Norfolk UK 130 question food frequency questionnaire) and breast cancer (i) risk factors and (ii) prognostic factors are described for 1797 women who had complete data for all covariates and phytoestrogens of interest. Isoflavone intakes were higher in the patients who were younger at diagnosis, in the non-smokers, those who had breast-fed and those who took supplements. Lignan intakes were higher in patients with a higher age at diagnosis, in ex-smokers, those who had breast-fed, who took supplements, had a lower BMI at diagnosis, lower age at menarche and were nulliparous. No significant associations between pre-diagnosis phytoestrogen intake and factors associated with improved breast cancer prognosis were observed. The potential for further exploration of the relationship between phytoestrogens and breast cancer recurrence and survival, and for the establishment of evidence to improve dietary and lifestyle advice offered to patients following breast cancer diagnosis using DietCompLyf data is discussed. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Experimental and epidemiological evidence suggest that a diet with dietary fat as low as 20% of kcal may be necessary to reduce the risk of breast cancer. Two groups of women, postmenopausal women treated for breast cancer and premenopausal women with cystic breast disease accompanied by cyclical mastaligia, participated in an intervention program to determine the feasibility of such a low-fat diet. After 3 mo of intervention both groups were consuming a low-fat diet; in the premenopausal groups serum estrogen levels decreased in response to the fat reduction. Other nutrition-education programs in research institutions, restaurants, and schools are attempting to influence the public's knowledge and behavior regarding the importance of dietary fat reduction.
OBJECTIVES To examine the relationship between fruit and vegetable intake, physical activity, and all-cause mortality in older women. DESIGN Six Cox proportional hazards models examined independent and additive relationships between physical activity, carotenoids, and all-cause mortality. Additional models tested whether physical activity and carotenoids were conjointly related to mortality. Models were adjusted for age, education, and race and ethnicity. SETTING Baltimore, Maryland. PARTICIPANTS Seven hundred thirteen women aged 70 to 79 participating in the Women’s Health and Aging Studies. MEASUREMENTS Total serum carotenoids, a marker of fruit and vegetable intake, and physical activity were measured at baseline. Physical activity was measured according to kilocalorie expenditure. RESULTS During 5 years of follow-up, 82 (11.5%) participants died. Measured continuously, physical activity improved survival (HR = 0.52, 95% CI = 0.41–0.66, P < .001). The most active women were more likely to survive than the least physically active women (HR = 0.28, 95% CI = 0.13–0.59, P < .001). Continuous measures of carotenoids improved survival (HR = 0.67, 95% CI = 0.51–0.89, P = .01). Women in the highest tertile of total carotenoids were more likely to survive those in the lowest (HR = 0.50, 95% CI = 0.27–0.91, P = .03). When examined in the same model, continuous measures of physical activity (HR = 0.54, 95% CI = 0.42–0.68, P < .001) and carotenoids (HR = 0.76, 95% CI = 0.59–0.98, P = .04) predicted survival during follow-up. CONCLUSION The combination of low total serum carotenoids and low physical activity, both modifiable risk factors, strongly predicted earlier mortality. These findings provide preliminary support that higher fruit and vegetable intake and exercise improve survival.
Background. Flax is a food and dietary supplement commonly used for menopausal symptoms. Flax is known for its lignan, α-linolenic acid, and fiber content, components that may possess phytogestrogenic, anti-inflammatory, and hormone modulating effects, respectively. We conducted a systematic review of flax for efficacy in improving menopausal symptoms in women living with breast cancer and for potential impact on risk of breast cancer incidence or recurrence. Methods. We searched MEDLINE, Embase, the Cochrane Library, and AMED from inception to January 2013 for human interventional or observational data pertaining to flax and breast cancer. Results. Of 1892 records, we included a total of 10 studies: 2 randomized controlled trials, 2 uncontrolled trials, 1 biomarker study, and 5 observational studies. Nonsignificant (NS) decreases in hot flash symptomatology were seen with flax ingestion (7.5 g/d). Flax (25 g/d) increased tumor apoptotic index (P < .05) and decreased HER2 expression (P < .05) and cell proliferation (Ki-67 index; NS) among newly diagnosed breast cancer patients when compared with placebo. Uncontrolled and biomarker studies suggest beneficial effects on hot flashes, cell proliferation, atypical cytomorphology, and mammographic density, as well as possible anti-angiogenic activity at doses of 25 g ground flax or 50 mg secoisolariciresinol diglycoside daily. Observational data suggests associations between flax and decreased risk of primary breast cancer (adjusted odds ratio [AOR] = 0.82; 95% confidence interval [CI] = 0.69-0.97), better mental health (AOR = 1.76; 95% CI = 1.05-2.94), and lower mortality (multivariate hazard ratio = 0.69; 95% CI = 0.50-0.95) among breast cancer patients. Conclusions. Current evidence suggests that flax may be associated with decreased risk of breast cancer. Flax demonstrates antiproliferative effects in breast tissue of women at risk of breast cancer and may protect against primary breast cancer. Mortality risk may also be reduced among those living with breast cancer. © The Author(s) 2013.
BACKGROUND: Heterocyclic amines, mutagens formed in meats cooked at high temperatures, have been demonstrated as mammary carcinogens in animals. We conducted a nested, case-control study among 41836 cohort members of the Iowa Women's Health Study to evaluate the potential role of heterocyclic amines and intake of well-done meat in the risk for human breast cancer. METHODS: A questionnaire was mailed to individuals in the cohort who had breast cancer diagnosed during the period from 1992 through 1994 and a random sample of cancer-free cohort members to obtain information on usual intake of meats and on meat preparation practices. Color photographs showing various doneness levels of hamburger, beefsteak, and bacon were included. Multivariate analysis was performed on data from 273 case subjects and 657 control subjects who completed the survey. RESULTS: A dose-response relationship was found between doneness levels of meat consumed and breast cancer risk. The adjusted odds ratios (ORs) for very well-done meat versus rare or medium-done meat were 1.54 (95% confidence interval [CI]=0.96-2.47) for hamburger, 2.21 (95% CI=1.30-3.77) for beef steak, and 1.64 (95% CI=0.92-2.93) for bacon. Women who consumed these three meats consistently very well done had a 4.62 times higher risk (95% CI=1.36-15.70) than that of women who consumed the meats rare or medium done. Risk of breast cancer was also elevated with increasing intake of well-done to very well-done meat. CONCLUSIONS: Consumption of well-done meats and, thus, exposures to heterocyclic amines (or other compounds) formed during high-temperature cooking may play an important role in the risk of breast cancer.
Modifiable factors, including diet, might alter breast cancer risk. We used the WHI Dietary Modification (DM) trial to test the effect of the intervention on risk of benign proliferative breast disease, a condition associated with increased risk of and considered to be on the pathway to invasive breast cancer. The WHI DM trial was a randomized, controlled, primary prevention trial conducted in 40 US clinical centers from 1993–2005. 48,835 postmenopausal women, aged 50–79 years, without prior breast cancer, were enrolled. Participants were randomly assigned to the DM intervention group or to the comparison group. The intervention was designed to reduce total dietary fat intake to 20% of total energy intake, and to increase fruit and vegetable intake to ≥5 servings/day and intake of grain products to ≥6 servings/day, but resulted in smaller, albeit significant changes in practice. Participants had biennial mammograms and regular clinical breast exams. We identified women who reported breast biopsies free of cancer, obtained the histologic sections, and subjected them to standardized central review. During follow-up (average, 7.7 years), 570 incident cases of benign proliferative breast disease were ascertained in the intervention group and 793 in the comparison group. The hazard ratio for the association between DM and benign proliferative breast disease was 1.09 (95%CI, 0.98–1.23). Risk varied by levels of baseline total vitamin D intake but it varied little by levels of other baseline variables. These results suggest that a modest reduction in fat intake and increase in fruit, vegetable, and grain intake does not alter the risk of benign proliferative breast disease.
Purpose Soy isoflavones, structurally similar to endogenous estrogens, may affect breast cancer through both hormonally-mediated and non-hormonally related mechanisms. Although the effects of soy are not well understood, some breast cancer survivors increase their soy intake post-diagnosis in attempt to improve their prognosis. Therefore, we examined the role of soy isoflavone intake and the risk of breast cancer recurrence by hormone receptor status, menopausal status, and tamoxifen therapy. Materials and methods A cohort of 1954 female breast cancer survivors, diagnosed during 1997–2000, was prospective followed for 6.31 years and 282 breast cancer recurrences were ascertained. Isoflavone intake was assessed by mailing modified Block and supplemental soy food frequency questionnaires to participants, on average 23 months post-diagnosis. Risk of breast cancer recurrence, measured by hazard ratios (HR) and 95% confidence intervals (CI), was estimated using multivariable delayed-entry Cox proportional hazards models. Results Suggestive trends for a reduced risk of cancer recurrence were observed with increasing quintiles of daidzein and glycetin intake compared to no intake among postmenopausal women (P for trend: P = .08 for daidzein, P = .06 for glycetin) and among tamoxifen users (P = .10 for daidzein, P = .05 for glycetin). Among postmenopausal women treated with tamoxifen, there was an approximately 60% reduction in breast cancer recurrence comparing the highest to the lowest daidzein intakes (>1453 micrograms (µg)/day versus < 7.7 µg/day) (HR, 0.48; 95% CI, 0.21–0.79, P = .008). Conclusion Soy isoflavones consumed at levels comparable to those in Asian populations may reduce the risk of cancer recurrence in women receiving tamoxifen therapy and moreover, appears not to interfere with tamoxifen efficacy. Further confirmation is required in other large prospective studies before recommendations regarding soy intake can be issued to breast cancer survivors.
Background The 2007 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) guidelines encourage cancer survivors to follow its cancer prevention recommendations. We evaluated whether adherence to the WCRF/AICR guidelines for cancer prevention was associated with lower mortality among older female cancer survivors. Methods From 2004–2009, 2,017 participants in the Iowa Women’s Health Study who had a confirmed cancer diagnosis (1986–2002) and completed the 2004 follow-up questionnaire were followed. Adherence scores for the WCRF/AICR guidelines for body weight, physical activity, and diet were computed assigning one, 0.5 or 0 points to each of eight recommendations depending on the degree of adherence. All-cause (n=461), cancer-specific (n=184), and cardiovascular disease (CVD)-specific mortality (n=145) were compared by the total adherence score and by adherence scores for each of the three components of the recommendations. Results Women with the highest (6–8) vs. lowest (0–4) adherence score had lower all-cause mortality (HR=0.67, 95%CI=0.50–0.94). Meeting the physical activity recommendation was associated with lower all-cause (ptrend<0.0001), cancer-specific (ptrend=0.04), and CVD-specific mortality (ptrend=0.03). Adherence to dietary recommendations was associated with lower all-cause mortality (ptrend<0.05), whereas adherence to the body weight recommendation was associated with higher all-cause mortality (ptrend=0.009). Conclusions Adherence to the WCRF/AICR guidelines was associated with lower all-cause mortality among older female cancer survivors. Adherence to the physical activity recommendation had the strongest association with lower all-cause and disease-specific mortality. Impact Older cancer survivors may decrease their risk of death by leading a healthy lifestyle after a cancer diagnosis.
BACKGROUND: Observational and preclinical studies suggest that dietary fiber intake may reduce the risk of breast cancer, but the results are inconclusive. OBJECTIVE: We aimed to examine the association between dietary fiber intake and risk of breast cancer by conducting a meta-analysis of prospective cohort studies. DESIGN: Relevant studies were identified by a PubMed database search through January 2011. Reference lists from retrieved articles were also reviewed. We included prospective cohort studies that reported RRs with 95% CIs for the association between dietary fiber intake and breast cancer risk. Both fixed- and random-effects models were used to calculate the summary risk estimates. RESULTS: We identified 10 prospective cohort studies of dietary fiber intake and risk of breast cancer involving 16,848 cases and 712,195 participants. The combined RR of breast cancer for the highest compared with the lowest dietary fiber intake was 0.89 (95% CI: 0.83, 0.96), and little evidence of heterogeneity was observed. The association between dietary fiber intake and risk of breast cancer did not significantly differ by geographic region, length of follow-up, or menopausal status of the participants. Omission of any single study had little effect on the combined risk estimate. Dose-response analysis showed that every 10-g/d increment in dietary fiber intake was associated with a significant 7% reduction in breast cancer risk. Little evidence of publication bias was found. CONCLUSION: This meta-analysis provides evidence of a significant inverse dose-response association between dietary fiber intake and breast cancer risk.
BACKGROUND: Evidence from case-control studies suggest that dietary fiber may be inversely related to breast cancer risk, but it is unclear if this is supported by prospective data. We conducted a systematic review and meta-analysis of the evidence from prospective studies. METHODS: PubMed was searched for prospective studies of fiber intake and breast cancer risk until 31st August 2011. Random effects models were used to estimate summary relative risks (RRs). RESULTS: Sixteen prospective studies were included. The summary RR for the highest versus the lowest intake was 0.93 [95% confidence interval (CI) 0.89-0.98, I(2) = 0%] for dietary fiber, 0.95 (95% CI 0.86-1.06, I(2) = 4%) for fruit fiber, 0.99 (95% CI 0.92-1.07, I(2) = 1%) for vegetable fiber, 0.96 (95% CI 0.90-1.02, I(2) = 5%) for cereal fiber, 0.91 (95% CI 0.84-0.99, I(2) = 7%) for soluble fiber and 0.95 (95% CI 0.89-1.02, I(2) = 0%) for insoluble fiber. The summary RR per 10 g/day of dietary fiber was 0.95 (95% CI 0.91-0.98, I(2) = 0%, P(heterogeneity) = 0.82). In stratified analyses, the inverse association was only observed among studies with a large range (≥13 g/day) or high level of intake (≥25 g/day). CONCLUSION: In this meta-analysis of prospective studies, there was an inverse association between dietary fiber intake and breast cancer risk.
Previous investigations, of adolescent diet recalled in adulthood, found lower risk for benign breast disease (BBD) with higher intakes of vegetable fat and nuts during high school. We investigate whether vegetable protein and fat, derived from diets reported during pre-adolescence and adolescence, are associated with subsequent risk for BBD in young women. The Growing Up Today Study includes 9,039 females, 9–15 years in 1996, who completed questionnaires annually through 2001, and then in 2003, 2005, 2007, and 2010. Food frequency questionnaires (1996–2001) obtained intake data on a variety of foods. Beginning in 2005, women (18–30 years) reported whether they had ever been diagnosed with BBD that was confirmed by breast biopsy (n = 112 cases). Logistic regression estimated associations between intakes of vegetable protein and fat and biopsy-confirmed BBD. Those individual foods that were the largest contributors of protein and fat in this cohort were also investigated. In analyses of intakes from 1996 through 1998, when our cohort was youngest, vegetable fat (OR = 0.72/(10 gm/day), 95 % CI 0.53–0.98; p = 0.04) was inversely associated with BBD risk. The greatest sources of vegetable fat and protein in these girls were peanut butter, peanuts, nuts, beans (beans, lentils, and soybeans), and corn. A daily serving of any one of these was associated with lower risk (OR = 0.32/(serv/day), 95 % CI 0.13–0.79; p = 0.01). Peanut butter (and nuts) at age 11 years was inversely associated with risk (p = 0.01). In analyses of intakes at age 14 years, vegetable protein was associated with lower BBD risk (OR = 0.64/(10 gm/day), 95 % CI 0.43–0.95; p = 0.03). A daily serving at 14 years of any one of the foods was associated with lower risk (OR = 0.34, 95 % CI 0.16–0.75; p = 0.01), as was peanut butter (and nuts) (p = 0.02). Girls with a family history of breast cancer had significantly lower risk if they consumed these foods or vegetable fat. In conclusion, consumption of vegetable protein, fat, peanut butter, or nuts by older girls may help reduce their risk of BBD as young women.
Background Previous research relating dietary fat, a modifiable risk factor, to pancreatic cancer has been inconclusive. Methods We prospectively analyzed the association between intakes of fat, fat subtypes, and fat food sources and exocrine pancreatic cancer in the National Institutes of Health–AARP Diet and Health Study, a US cohort of 308 736 men and 216 737 women who completed a 124-item food frequency questionnaire in 1995–1996. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards regression models, with adjustment for energy intake, smoking history, body mass index, and diabetes. Statistical tests were two-sided. Results Over an average follow-up of 6.3 years, 865 men and 472 women were diagnosed with exocrine pancreatic cancer (45.0 and 34.5 cases per 100 000 person-years, respectively). After multivariable adjustment and combination of data for men and women, pancreatic cancer risk was directly related to the intakes of total fat (highest vs lowest quintile, 46.8 vs 33.2 cases per 100 000 person-years, HR = 1.23, 95% CI = 1.03 to 1.46; Ptrend  = .03), saturated fat (51.5 vs 33.1 cases per 100 000 person-years, HR = 1.36, 95% CI = 1.14 to 1.62; Ptrend < .001), and monounsaturated fat (46.2 vs 32.9 cases per 100 000 person-years, HR = 1.22, 95% CI = 1.02 to 1.46; Ptrend = .05) but not polyunsaturated fat. The associations were strongest for saturated fat from animal food sources (52.0 vs 32.2 cases per 100 000 person-years, HR = 1.43, 95% CI = 1.20 to 1.70; Ptrend < .001); specifically, intakes from red meat and dairy products were both statistically significantly associated with increased pancreatic cancer risk (HR = 1.27 and 1.19, respectively). Conclusion In this large prospective cohort with a wide range of intakes, dietary fat of animal origin was associated with increased pancreatic cancer risk.
INTRODUCTION: Sex steroid exposure increases the risk of breast cancer by unclear mechanisms. Diet modifications may be one breast cancer prevention strategy. The proinflammatory cytokine family of IL-1 is implicated in cancer progression. IL-1Ra is an endogenous inhibitor of the proinflammatory IL-1α and IL-1β. OBJECTIVE: The objective of this study was to elucidate whether estrogen, tamoxifen, and/or diet modification altered IL-1 levels in normal human breast tissue. DESIGN AND METHODS: Microdialysis was performed in healthy women under various hormone exposures, tamoxifen therapy, and diet modifications and in breast cancers of women before surgery. Breast tissue biopsies from reduction mammoplasties were cultured. RESULTS: We show a significant positive correlation between estradiol and in vivo levels of IL-1β in breast tissue and abdominal sc fat, whereas IL-1Ra exhibited a significant negative correlation with estradiol in breast tissue. Tamoxifen or a dietary addition of 25 g flaxseed per day resulted in significantly increased levels of IL-1Ra in the breast. These results were confirmed in ex vivo culture of breast biopsies. Immunohistochemistry of the biopsies did not reveal any changes in cellular content of the IL-1s, suggesting that mainly the secreted levels were affected. In breast cancer patients, intratumoral levels of IL-1β were significantly higher compared with normal adjacent breast tissue. CONCLUSION: IL-1 may be under the control of estrogen in vivo and may be attenuated by antiestrogen therapy and diet modifications. The increased IL-1β in breast cancers of women strongly suggests IL-1 as a potential therapeutic target in breast cancer treatment and prevention.
BACKGROUND: Inconsistent associations have been reported between diet and breast cancer. OBJECTIVE: We prospectively examined the association between dietary patterns and postmenopausal breast cancer risk in a US-wide cohort study. DESIGN: Data were analyzed from 40 559 women who completed a self-administered 61-item Block food-frequency questionnaire in the Breast Cancer Detection Demonstration Project, 1987-1998; 1868 of those women developed breast cancer. Dietary patterns were defined by using principal components factor analysis. Cox proportional hazard regression was used to assess breast cancer risk. RESULTS: Three major dietary patterns emerged: vegetable-fish/poultry-fruit, beef/pork-starch, and traditional southern. The vegetable-fish/poultry-fruit pattern was associated with higher education than were the other patterns, but was similar in nutrient intake to the traditional southern pattern. After adjustment for confounders, there was no significant association between the vegetable-fish/poultry-fruit and beef/pork-starch patterns and breast cancer. The traditional southern pattern, however, was associated with a nonsignificantly reduced breast cancer risk among all cases (in situ and invasive) that was significant for invasive breast cancer (relative hazard = 0.78; 95% CI = 0.65, 0.95; P for trend = 0.003). This diet was also associated with a reduced risk in women without a family history of breast cancer (P = 0.05), who were underweight or normal weight [body mass index (in kg/m(2)) < 25; P = 0.02], or who had tumors positive for estrogen receptor (P = 0.01) or progesterone receptor (P = 0.003). Foods in the traditional southern pattern associated with reduced breast cancer risk were legumes, low mayonnaise-salad dressing intake, and possibly cabbage. CONCLUSIONS: The traditional southern diet or its components are associated with a reduced risk of invasive breast cancer in postmenopausal women.
This case-control study examined different food groups in relation to breast cancer. Between 2002 and 2004, 437 cases and 922 controls matched according to age and area of residence were interviewed. Diet was measured by a validated food frequency questionnaire. Adjusted odds ratios (Ors) were computed across levels of various dietary intakes identified by two methods: the "classical" and the "spline" methods. Neither of the 2 methods found an association between total fruit and vegetable consumption and breast cancer. Results of the 2 methods showed a nonsignificant decreased association with cooked vegetables intake as well as legumes and fish consumption. Whereas the spline method showed no association, the classical method showed significant associations related to the lowest consumption of raw vegetables or dairy products and breast cancer risk: Adjusted OR for raw vegetable consumption between (67.4 and 101.3 g/day) vs. (< 67.4 g/day) was 0.63 [95% confidence interval (CI) = 0.43-0.93]. Adjusted OR for dairy consumption between (134.3 and 271.2 g/day) vs. (< 134.3 g/day) was 1.57 (95% CI = 1.06-2.32). However, the overall results were not consistent. Compared to the classical method, the use of the spline method showed a significant association for cereal, meat, and olive oil. Cereal and olive oil were inversely associated with breast cancer risk. Breast cancer risk increased by 56% for each additional 100 g/day of meat consumption. Studies using novel methodological techniques are needed to confirm the dietary threshold responsible for changes in breast cancer risk. New approaches that consist in analyzing dietary patterns rather than dietary food are necessary.
Although breast and ovarian cancers are rare in Japan compared with other developed countries, the death rates for both are increasing. In Japan, dramatic lifestyle changes occurred after World War II. Over the past 50 years (1947-1997), the age-standardized death rates of breast and ovarian cancers increased about 2- and 4-fold, respectively, and the respective intake of milk, meat, and eggs increased 20-, 10-, and 7-fold. The increase in the annual death rates from breast and ovarian cancers might be due to the lifestyle changes (increased consumption of animal-derived food) that occurred after 1945. Among the food, milk and dairy products should receive particular attention since they contain considerable amounts of estrogens.
Grapefruit inhibits cytochrome P450 3A4 and may affect estrogen metabolism. In the European Prospective Investigation into Cancer and Nutrition (EPIC), we examined the relationships of grapefruit intake with risk of breast cancer and with serum sex hormone levels. 114,504 women with information on dietary intake of grapefruit and on reproductive and lifestyle risk factors were followed for a median 9.5 years and 3,747 incident breast cancers were identified. Fifty-nine percent of women reported eating grapefruit, 4% ate > or = 60 g/day. Cox proportional hazard models were used to estimate the hazard ratio (HR) for breast cancer according to grapefruit intake, adjusting for study centre, reproductive factors, body mass index, energy intake, and alcohol intake. Grapefruit intake was not related to the risk of breast cancer: compared with women who ate no grapefruit, women with the highest intake of > or =60 g/day had a HR of 0.93 (95% CI 0.77-1.13), p for linear trend = 0.5. There was no relationship between grapefruit intake and breast cancer risk among premenopausal women, all postmenopausal women, or postmenopausal women categorized by hormone replacement therapy use (all p>0.05). There was no association between grapefruit intake and estradiol or estrone among postmenopausal women. In this study, we found no evidence of an association between grapefruit intake and risk of breast cancer.
BACKGROUND: The association between consumption of multivitamins and breast cancer is inconsistent in epidemiologic studies. OBJECTIVE: To perform a meta-analysis of cohort and case-control studies to evaluate multivitamin intake and its relationship with breast cancer risk. METHODS: The published literature was systematically searched and reviewed using MEDLINE (1950 through July 2010), EMBASE (1980 through July 2010), and the Cochrane Central Register of Controlled Trials (The Cochrane Library 2010 issue 1). Studies that included specific risk estimates were pooled using a random-effects model. The bias and quality of these studies were assessed with REVMAN statistical software (version 5.0) and the GRADE method of the Cochrane Collaboration. RESULTS: Eight of 27 studies that included 355,080 subjects were available for analysis. The total duration of multivitamin use in these trials ranged from 3 to 10 years. The frequency of current use in these studies ranged from 2 to 6 times/week. In analyses by duration of use 10 years or longer or 3 years or longer and by frequency 7 or more times/week that were reported in these studies, multivitamin use was not significantly associated with the risk of breast cancer. Only 1 recent Swedish cohort study concluded that multivitamin use is associated with an increased risk of breast cancer. The results of a meta-analysis that pooled data from 5 cohort studies and 3 case-control studies indicated that the overall multivariable relative risk and odds ratio were 0.10 (95% CI 0.60 to 1.63; p = 0.98) and 1.00 (95% CI 0.51 to 1.00; p = 1.00), respectively. The association was not statistically significant. CONCLUSIONS: Multivitamin use is likely not associated with a significant increased or decreased risk of breast cancer, but these results highlight the need for more case-control studies or randomized controlled clinical trials to further examine this relationship.
Oestrogen is an important determinant of breast cancer risk. Oestrogen-mimicking plant compounds called phytoestrogens can bind to oestrogen receptors and exert weak oestrogenic effects. Despite this activity, epidemiological studies suggest that the incidence of breast cancer is lower in countries where the intake of phytoestrogens is high, implying that these compounds may reduce breast cancer risk, and possibly have an impact on survival. Isoflavones and lignans are the most common phytoestrogens in the diet. In this article, we present findings from human observational and intervention studies related to both isoflavone and lignan exposure and breast cancer risk and survival. In addition, the clinical implications of these findings are examined in the light of a growing dietary supplement market. An increasing number of breast cancer patients seek to take supplements together with their standard treatment in the hope that these will either prevent recurrence or treat their menopausal symptoms. Observational studies suggest a protective effect of isoflavones on breast cancer risk and the case may be similar for increasing lignan consumption although evidence so far is inconsistent. In contrast, short-term intervention studies suggest a possible stimulatory effect on breast tissue raising concerns of possible adverse effects in breast cancer patients. However, owing to the dearth of human studies investigating effects on breast cancer recurrence and survival the role of phytoestrogens remains unclear. So far, not enough clear evidence exists on which to base guidelines for clinical use, although raising patient awareness of the uncertain effect of phytoestrogens is recommended.
To correct methodologic flaws (Type II error, confounding variables, and nonblinding) in previous studies relating infant feeding to later obesity, we conducted case-control studies of 639 patients 12 to 18 years of age attending our Adolescent Clinic, and 533 similarly aged healthy children attending a Montreal high school. Each subject was classified as either obese, overweight, or nonobese based on measurements of height, weight, and triceps and subscapular skinfolds. Feeding history, family history, and demographic data were later ascertained "blindly" by telephone interview. Analysis of the raw data revealed a significantly elevated estimated relative risk of not breast-feeding and a significant trend for rates of breast-feeding among the three weight groups. The magnitude of the protective effect appeared to rise slightly with increased duration of breast-feeding. Delayed introduction of solid foods provided little if any additional benefit. Several demographic and clinical variables proved to be confounding, but the significant protective effect of breast-feeding persisted even after controlling for confounders. We conclude that breast-feeding does protect against later obesity and attribute the conflicting results of previous studies to insufficient attention to methodologic standards.
Emerging evidence suggests that statins' may decrease the risk of cancers. However, available evidence on breast cancer is conflicting. We, therefore, examined the association between statin use and risk of breast cancer by conducting a detailed meta-analysis of all observational studies published regarding this subject. PubMed database and bibliographies of retrieved articles were searched for epidemiological studies published up to January 2012, investigating the relationship between statin use and breast cancer. Before meta-analysis, the studies were evaluated for publication bias and heterogeneity. Combined relative risk (RR) and 95 % confidence interval (CI) were calculated using a random-effects model (DerSimonian and Laird method). Subgroup analyses, sensitivity analysis, and cumulative meta-analysis were also performed. A total of 24 (13 cohort and 11 case-control) studies involving more than 2.4 million participants, including 76,759 breast cancer cases contributed to this analysis. We found no evidence of publication bias and evidence of heterogeneity among the studies. Statin use and long-term statin use did not significantly affect breast cancer risk (RR = 0.99, 95 % CI = 0.94, 1.04 and RR = 1.03, 95 % CI = 0.96, 1.11, respectively). When the analysis was stratified into subgroups, there was no evidence that study design substantially influenced the effect estimate. Sensitivity analysis confirmed the stability of our results. Cumulative meta-analysis showed a change in trend of reporting risk of breast cancer from positive to negative in statin users between 1993 and 2011. Our meta-analysis findings do not support the hypothesis that statins' have a protective effect against breast cancer. More randomized clinical trials and observational studies are needed to confirm this association with underlying biological mechanisms in the future.
Acrylamide is a probable human carcinogen, with industrial contact, tobacco smoking and foods processed at high temperatures as the main routes of exposure. In animal studies oral intake of acrylamide has been related to cancer development, with indications that the increased cancer occurrence especially regards endocrine related tumors. In human epidemiological studies, dietary exposure to acrylamide has also been suggested related to higher risk of endocrine related tumors, like estrogen sensitive breast cancer. The aim of the present study was to evaluate if pre-diagnostic acrylamide exposure, measured by acrylamide and glycidamide hemoglobin adducts (AA-Hb and GA-Hb), were associated to mortality in breast cancer cases. Among 24,697 postmenopausal women included into a Danish cohort between 1993 and 1997, 420 developed breast cancer before 2001 and 110 died before 2009. AA-Hb and GA-Hb concentrations measured in blood samples were related to mortality by Cox proportional hazard models. Estimates are given per 25 pmol/g globin higher levels. Among non-smokers, higher concentrations of GA-Hb were associated to a higher hazard rate of breast cancer specific mortality (HR (95% CI): 1.63 (1.06-2.51)), the hazard rate among women diagnosed with estrogen receptor positive tumors was (HR (95% CI): 2.23 (1.38-3.61)). For AA-Hb the tendency was similar, but only statistically significant among those with estrogen receptor positive tumors (HR (95% CI): 1.31 (1.02-1.69)). In conclusion, the present study indicates that pre-diagnostic exposure to acrylamide may be related to mortality among breast cancer patients and that this may especially concern the most endocrine related type of breast cancer. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.