The present nested case-control study was designed to investigate whether the association between carotenoid consumption and risk of breast cancer is related to mammographic density. High breast density as measured by mammography has been reported to be a powerful indicator of increased breast cancer risk. The study included 604 breast cancer cases and 626 cancer-free controls in the Nurses' Health Study for whom circulating carotenoid (alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, and lutein/zeaxanthin) levels had been measured and mammograms obtained prospectively. Using a computer-assisted method to determine mammographic density, circulating carotenoids were not found to be associated with mammographic density. However, mammographic density significantly influenced the association between total circulating carotenoids and risk of breast cancer (P heterogeneity = 0.008). Total circulating carotenoid levels were found to be inversely associated with overall breast cancer risk (P trend = 0.01). Among women in the highest third of mammographic density, total circulating carotenoids were associated with a 50% lower risk of breast cancer (odds ratio = 0.5; 95% confidence interval = 0.3 - 0.8). Similarly, among these women, high levels of circulating alpha-carotene, beta-cryptoxanthin, lycopene, and lutein/zeaxanthin were found to be associated with a significant 40% to 50% reduction in risk of breast cancer (P trend < 0.05). On the other hand, no such inverse association was observed between circulating carotenoids and breast cancer risk among study participants with low mammographic density. The authors conclude that plasma levels of carotenoids may play a role in reducing risk of breast cancer, especially among women with high breast density.

The present prospective study was designed to investigate the association between meat, egg, and dairy product consumption and risk of breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) study cohort. Information concerning diet was collected from 319,826 women during the period 1992 - 2003. During a median follow-up period of 8.8 years, 7,119 breast cancer cases were diagnosed. Multivariate Cox proportional hazard models were used to calculate disease hazard ratios. No consistent overall association was found between risk of breast cancer and consumption of any of the food groups under study. High consumption of processed meat was associated with a modest increase in breast cancer risk in the categorical model (hazard ratio: 1.10; 95% CI: 1.00 - 1.20; highest versus with lowest quintile: P for trend = 0.07). An association of breast cancer risk with butter consumption for premenopausal women was suggested in subgroup analysis (hazard ratio: 1.28; 95% CI: 1.06 - 1.53; highest compared with lowest quintile: P for trend = 0.21). Between-country heterogeneity was found for red meat consumption (Q statistic = 18.03; P = 0.05) and was significantly explained by the proportion of meat cooked at high temperature (P = 0.023). The authors conclude that they had not consistently identified intakes of meat, eggs, or dairy products as risk factors for breast cancer.

The current case-control study was designed to investigate the associations of dietary intakes of choline and betaine and breast cancer risk and mortality. Choline and betaine both provide methyl groups for one-carbon metabolism. These nutrients can be obtained from a wide variety of foods. Betaine can also be synthesized in the body from its precursor, choline. Animal studies have suggested a causal relationship between choline deficiency and the development of cancer, however, the role of these two nutrients in human carcinogenesis and cancer progression is not well understood. The study included 1,508 women in the population-based Long Island Breast Cancer Study Project, among whom 308 died (164 from breast cancer) by year-end 2005. There was an indication that higher intake of free choline was associated with lower risk of breast cancer (Ptrend=0.04). Higher intakes of free choline, betaine, and phosphocholine each were found to be associated with lower all-cause mortality as well as breast cancer-specific mortality in a dose-dependent manner. The authors also examined associations between polymorphisms of three key choline- and betaine-metabolizing genes and breast cancer mortality. The betaine-homocysteine methyltransferase gene (BHMT) rs3733890 polymorphism was found to be associated with decreased breast cancer-specific mortality (hazard ratio = 0.64; 95% confidence interval = 0.42 - 0.97). The authors conclude that choline and betaine have important roles in breast carcinogenesis and they comment that high intake of these nutrients may be a promising strategy to prevent the development of breast cancer and to reduce its mortality.

The current case-control study was designed to compare the diets of a group of Korean breast cancer patients with a healthy control group. The cases included 97 women with newly confirmed diagnoses of breast cancer at the inpatient or outpatient clinic of Yeouido St. Mary’s Hospital in Seoul, and excluded women with any history of liver diseases, diabetes mellitus, respiratory disorders and cardiovascular diseases. The 97-person control group also excluded women with known malignant, hormonal, gynecological or endocrine diseases. Intake of nutrients in 117 food items were estimated in the breast cancer patients and age-matched healthy controls using a quantitative food frequency questionnaire administered by a trained dietitian. The questionnaire also included general information (age, sex and marital status), age at menarche, and pregnancy history. It was found that the average caloric intake of the breast cancer patients and the healthy controls did not differ significantly. However, the breast cancer patients consumed significantly less fat and antioxidant nutrients such as vitamin A, retinol, beta-carotene, vitamin C and vitamin E than did the controls. Consumption of eggs (p<0.01), legumes (p<0.05), vegetables (p<0.05), seasonings (p<0.001), and oils and fats (p<0.01) was significantly lower in the breast cancer patients. However, the level of energy from fat is relatively low in Korean patients compared to their Western counterparts, and fat consumption may not be an independent risk factor at this level of intake. With respect to particular foods, in addition to eggs, the breast cancer patients consumed a significantly lower quantity of bean curd (tofu), onion, garlic, green pepper, sweet pepper, kale, cucumber, seasoned bean sprouts, sesame leaf, zucchini, radish, mushroom, crown daisy, red pepper paste, bean paste, spicy bean paste, orange juice, grape juice, and tomato juice than the controls. On the other hand, the breast cancer patients consumed significantly greater quantities of cooked rice, noodles, deep fried chicken, satsuma mandarin, Korean melon, kimchi and coffee than the controls. The authors conclude that since the breast cancer patients consumed less soy and vegetables, they had a lower intake than the controls of rich sources of antioxidant nutrients, phytosterols, fiber and non-nutritional components that may reduce the risk of cancer. In addition, the breast cancer patients in this study consumed lower quantities of red pepper paste, bean paste and spicy bean paste, causing their intake of pepper flavonols (which may have a protective effect on breast cancer risk) to be lower than that of the controls.

The present prospective cohort study was designed to examine the association between nutrients and ovarian cancer risk among the eligible women in the California Teachers Study. Of the 97,275 women who provided a baseline dietary assessment during the 1995-1996 period, 280 women developed ovarian cancer by year-end 2003. Intake of isoflavones was found to be associated with lower risk of ovarian cancer. The relative risk of ovarian cancer associated with intake of more than 3 mg of total isoflavones per day compared to lower than 1 mg/day was 0.56 (95% confidence interval: 0.33, 0.96). Intake of isothiocyanates was not associated with ovarian cancer risk, nor was intake of macronutrients, antioxidant vitamins, or other micronutrients. In particular, consumption of dairy products, milk, coffee, tea, or eggs was not associated with risk of ovarian cancer. The authors conclude that although dietary consumption of isoflavones may be associated with decreased ovarian cancer risk, most dietary factors are unlikely to play a major role in ovarian cancer development.

This article details the needs of women for omega-3 fatty acids, including alpha linoleic acid, eicosapentaenoic acid, and docosahexaenoic acid. Reserves of omega-3 fatty acids in a woman's adipose tissue are vital for the developing fetus and the breast-fed newborn infant. Docosahexaenoic acid and eicosapentaenoic acid have been found to be important for preventing cardiovascular disease in women. Omega-3 fatty acids can help reduce the risk of certain cancers, including those of the breast and colon, and possibly of the uterus and the skin. They are also thought to reduce the risk of manic-depressive psychosis, postpartum depression, dementia, hypertension, toxemia, diabetes and, to some extend, age-related macular degeneration. The typical western diet contains less than 50% of the RDA of little alpha linoleic acid. Good sources include rapeseed oil (canola oil), walnuts and omega-3 enhanced eggs (similar to wild-type eggs). Intake of eicosapentaenoic acid and docosahexaenoic acid varies widely from person to person. The only good dietary sources are fish, seafood, and "omega-3" eggs.

The present case-control study was designed to assess the association between diet and risk of breast cancer in women participating in a trial of breast self exam in Shanghai, China. Breast cancer rates have been found to more than double in Chinese women when they migrate from China to Hong Kong to the United States, which suggests that environmental factors contribute to the international differences in incidence. Dietary factors such as intake of soy, meat, and fruits and vegetables, which differ between the Chinese and United States populations, have been proposed as breast cancer risk factors. In the study, 378 breast cancer cases and 1,070 frequency age-matched controls completed both a comprehensive food questionnaire and a risk factor survey. After adjusting for age, total energy intake, and total years of breast-feeding, women in the highest fourth of fruit and vegetable intake (3.8 servings/day) were found to be significantly less likely to have breast cancer (odds ratio (OR) = 0.48; 95% confidence interval (CI), 0.29-0.78) compared to women in the lowest quartile of intake (2.3 servings/day). Egg consumption was also significantly inversely associated with risk of breast cancer (OR for 6.0 eggs/week versus 2.0 eggs/wk = 0.56; 95% CI, 0.35-0.91) and there was a 40% reduction in risk of breast cancer among women who used sesame oil for cooking compared with those that did not. There was no observed difference in soy consumption between cases and controls. The strong inverse relationship between consumption of fruits and vegetables and breast cancer risk was not explained by any single botanical family.

The current case-control study was designed to determine the associations between diet in early life and the risk of breast cancer in adulthood. The study was conducted among participants in the Nurses' Health Study who completed a questionnaire about their diets during high school. 843 eligible cases were matched with controls on the basis of age. It was found that women who had consumed more eggs, vegetable fat and fiber during high school had a lower risk of breast cancer. Women who consumed more butter had a higher risk.

The relationship between breast cancer incidence and diet was studied in the Nurses' Health Study cohort. 88,647 women were followed for 18 years, during which there were five assessments of diet using questionnaire. 4,107 women developed breast cancer during the follow-up period. The relative risks (RR) with 95% confidence interval (CI) of breast cancer for the highest quintile of intake compared to the lowest quintile were 1.02 (0.92-1.14) for animal protein, 0.93 (0.83-1.05) for red meat and 0.89 (0.79-1.00) for all meat. The results did not differ by menopausal status or family history of breast cancer. The authors conclude that there was no evidence that intake of meat or fish during mid-life and later was associated with the risk of breast cancer.

The current study combined the primary data from eight prospective North American and Western European cohort studies, each of which contained at least 200 breast cancer cases. The aggregated database included 351,041 women, of whom 7379 of whom were diagnosed with invasive breast cancer during up the follow-up period of up to 15 years. The study found no significant relationships between risk of breast cancer and consumption of total meat, red meat, white meat, total dairy fluids, or total dairy solids. Compared to women who did not eat eggs, breast cancer risk was slightly decreased for women who consumed fewer than two eggs per week but slightly increased among women who consumed one or more eggs per day. There authors concluded that there were no significant associations between the intake of meat or dairy products and the risk of breast cancer. They further stated that the inconsistent association between egg consumption and risk of breast cancer merited further investigation.