Lower Breast Cancer Risk among Women following the World Cancer Research Fund and American Institute for Cancer Research Lifestyle Recommendations: EpiGEICAM Case-Control Study

Abstract

BackgroundAccording to the “World Cancer Research Fund” and the “American Institute of Cancer Research” (WCRF/AICR) one in four cancer cases could be prevented through a healthy diet, weight control and physical activity.ObjectiveTo explore the association between the WCRF/AICR recommendations and risk of breast cancer.MethodsDuring the period 2006 to 2011 we recruited 973 incident cases of breast cancer and 973 controls from 17 Spanish Regions. We constructed a score based on 9 of the WCRF/AICR recommendations for cancer prevention:: 1)Maintain adequate body weight; 2)Be physically active; 3)Limit the intake of high density foods; 4)Eat mostly plant foods; 5)Limit the intake of animal foods; 6)Limit alcohol intake; 7)Limit salt and salt preserved food intake; 8)Meet nutritional needs through diet; S1)Breastfeed infants exclusively up to 6 months. We explored its association with BC by menopausal status and by intrinsic tumor subtypes (ER+/PR+ & HER2-; HER2+; ER&PR-&HER2-) using conditional and multinomial logistic models respectively.ResultsOur results point to a linear association between the degree of noncompliance and breast cancer risk. Taking women who met 6 or more recommendations as reference, those meeting less than 3 showed a three-fold excess risk (OR=2.98(CI95%:1.59-5.59)), especially for postmenopausal women (OR=3.60(CI95%:1.24;10.47)) and ER+/PR+&HER2- (OR=3.60(CI95%:1.84;7.05)) and HER2+ (OR=4.23(CI95%:1.66;10.78)) tumors. Noncompliance of recommendations regarding the consumption of foods and drinks that promote weight gain in premenopausal women (OR=2.24(CI95%:1.18;4.28); p for interaction=0.014) and triple negative tumors (OR=2.93(CI95%:1.12-7.63)); the intake of plant foods in postmenopausal women (OR=2.35(CI95%:1.24;4.44)) and triple negative tumors (OR=3.48(CI95%:1.46-8.31)); and the alcohol consumption in ER+/PR+&HER2- tumors (OR=1.52 (CI95%:1.06-2.19)) showed the strongest associations.ConclusionBreast cancer prevention might be possible by following the “World Cancer Research Fund” and the “American Institute of Cancer Research” recommendations, even in settings like Spain, where a high percentage of women already comply with many of them.

Adherence to the World Cancer Research Fund/American Institute for Cancer Research recommendations and breast cancer risk

“…Five prospective studies and two case–control studies have examined the association between adherence to the WCRF/AICR recommendations or similar recommendations (American Cancer Society guidelines) and breast cancer risk, but only one of these studies included the dietary supplement recommendation in their evaluation. The majority of previous studies observed that adherence to cancer prevention guidelines was associated with a reduction in breast cancer risk with a range of risk reduction from 6 to 13% for each individual guideline met . Our results are consistent with these studies as we observed an 11% reduction in risk for each recommendation met.…”

“…Since then, evaluation of these recommendations has suggested that adherence to the recommendations reduces overall cancer incidence and cancer mortality . The association between adherence to the WCRF/AICR recommendations and breast cancer risk has also been examined in six studies with the consensus being that adherence to the recommendation reduces breast cancer risk by approximately 6–13% for each guideline met . However, breast cancer was the primary focus in only four of these studies, of which just two were prospective studies and only two examined the associations by hormone receptor subtype, and just one case–control study included the dietary supplements recommendation in its evaluation …”

Primary and secondary prevention of breast cancer

“…Physical activity has a positive impact on mental health among patients suffering from malign tumours [36], and is defined as each body movement made by the skeletal muscles that results in energy consumption [37]. The connection between breast cancer and physical activity is stronger among women who have undergone the menopause [5], have a negative family history regarding this cancer and maintain proper body weight, as well as among women who have given birth to at least one healthy baby [38]. Epidemiological research suggests that the intensity of exercises, starting from moderate to energetic, reduces the risk of breast cancer by roughly 10-25%, compared to inactive women.…”

“…It is also the first most frequently occurring cancer among women [1,2,3], comprising 25.2% of all newly-diagnosed cancers [1]. It is assumed that one in eight women in the world will develop mammary gland cancer [4], and that only 5-10% of all cases of this cancer are caused by genetic disorders, whereas the remaining 90-95% of cases are connected to environmental factors and life style [5]. Therefore, an essential element of modern medicine is to conduct multidisciplinary research targeted at the enhancing efficiency of health prevention by focusing on primary prevention, risk factors modification to early detection of the disease, quick beginning of treatment (secondary prevention), as well as observation.…”

Exercise and weight loss interventions and miRNA expression in women with breast cancer

“…Only 10% of BC cases are due to a genetic predisposition, indicating that a number of environmental and anthropometric factors affect BC risk 4–8 . Lifestyle factors associated with higher BC risk include poor diet, alcohol intake, and smoking 9–11 . Studies consistently indicate post-menopausal women who are obese have an increased risk for breast-cancer specific mortality as compared to women with a normal BMI both prior to- and post-diagnosis 12–14 .…”