Research Article Association of Mammographic Breast Density with Dairy Product Consumption, Sun Exposure, and Daily Activity Sadaf Alipour, 1,2 Azin Saberi, 1 Afsaneh Alikhassi, 3 Leila Bayani, 4 and Ladan Hosseini 5 1 Surgery Department, Arash Women’s Hospital, Tehran University of Medical Sciences, Tehran, Iran 2 Vali-e-Asr Reproductive Health Research Center, Tehran University of Medical Sciences, Tehran, Iran 3 Radiology Department, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran 4 Radiology Department, Arash Women’s Hospital, Tehran University of Medical Sciences, Tehran, Iran 5 Research Development Center, Arash Women’s Hospital, Tehran University of Medical Sciences, Tehran, Iran Correspondence should be addressed to Sadaf Alipour; sadafalipour@yahoo.com Received 12 December 2013; Accepted 22 January 2014; Published 4 March 2014 Academic Editors: G. Gatti and M. Loizidou Copyright © 2014 Sadaf Alipour et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background. Mammographic density is a risk factor, for breast cancer and its association with various factors is under investigation; we carried out a study to assess its relationship with daily dairy intake, sun exposure, and physical activities. Patients and Methods. Women ≥40 years of age were interviewed about habits of dairy product consumption, daily sun exposure and physical activity. Exclusion criteria consisted of history of breast cancer, consumption of calcium and vitamin D supplements, hormone replacement therapy, or renal disease. Mammographic densities were classifed according to the classifcation system of the American College of Radiologists into 4 classes. Results. Overall 703 cases were entered in the study. Te mean age was 48.2±6.2 years. Te most common and least frequent classes of mammographic density were classes 2 and 4, respectively. Tere was no signifcant association between mammographic density and rate of dairy consumption, amount of sunlight exposure, and daily physical activity. Conclusion. Relation of sunlight exposure and intake of milk products with mammographic density need further study, while the subject of physical activity can be evaluated by a systematic review and meta-analysis of the existing literature. 1. Introduction Density of breast parenchyma in mammography is presently a feature recognized as one of the risk factors for breast cancer [1–3]. Relative risk for breast cancer in high density mammograms is 2- to 6-fold higher than in low density ones [1, 2, 4]. Among factors recognized as potentially capable of infuencing mammographic density (MD), hormonal related issues [5, 6], body mass index [7, 8], age [9], and some dietary factors have been implicated [10–12]. As well, other likely related topics, including anthropometric characteristics [13], smoking [14, 15], metabolic syndromes [16], sun exposure [17], and physical activity [18, 19], have been investigated. We conducted a study to determine the association of mammographic breast density with habits of dairy intake, daily sun exposure, and rate of daily activities. 2. Methods Tis is a cross-sectional study completed as component of a large study being carried out in the Breast Clinic of Arash Women’s Hospital, Tehran, Iran. Women aged 40 years or above who were candidates for breast cancer screening were entered in the study and those who were practicing sports or had a personal history of breast cancer, recent consumption of calcium supplements, vitamin D, or hormone replacement therapy (HRT), or any kind of renal disease were excluded. A questionnaire about habitual daily sun exposure, patterns of consumption of dairy products, and amount of daily activity of participants was flled out by a trained inter- viewer. Following clinical breast examination, all of them underwent screening mammography by standard bilateral mediolateral-oblique and craniocaudal views. Two expert radiologists classifed the density of mammograms according Hindawi Publishing Corporation ISRN Oncology Volume 2014, Article ID 159049, 6 pages http://dx.doi.org/10.1155/2014/159049