Table 2.

Studies about association of MD with dairy product intake, sunlight exposure, or physical activity.

Authors	Studied factor	Pub yr*	Study design and details	Type of association
Bérubé et al. [31]	Calcium containing foods**	2004	(i) Semiquantitative food frequency questionnaire (ii) MD assessed by one expert reviewer evaluating percent density (iii) 1092 women 40 to 60 years old with recent 2 years screening mammogram	Inverse
Bérubé et al. [32]	Calcium containing foods**	2005	(i) 777 premenopausal and 783 post-menopausal women (ii) Food frequency questionnaire for estimation of dietary intake (iii) MD assessed by computer-assisted method	Inverse
Masala et al. [33]	Cheese ad dietary calcium	2006	(i) 2,000 women with mammogram taken 5 years after enrollment in the EPIC-Florence study (ii) Original mammograms retrieved (iii) Information on dietary habits collected during 5 years (iv) MD assessed according to Wolfe's classification	Inverse
Takata et al. [34]	Dairy products	2007	(i) 3512 mammograms from 1250 premenopausal and postmenopausal women (ii) MD assessed by computer-assisted method (iii) Validated food frequency questionnaire for estimation of dietary intake	None
Thomson et al. [10]	Dairy products	2007	(i) Cross-sectional design (ii) MD assessed by computer-assisted method (iii) Arizona food frequency questionnaire for estimation of dietary intake	Inverse
Mishra et al. [35]	Dietary calcium from childhood	2008	(i) cohort of 1161 women followed up since their birth (ii) documentation of diet at age 4 by 24 h recalls and at age 36, 43 and 53 by 5-day food records (iii) MD assessed by computer-assisted method	None***
Wu et al.**** [17]	Sunlight	2013	(i) 650 premenopausal women (ii) validated sunlight exposure questionnaire via telephone (iii) MD classified according to Tabar's classification	Inverse
Peplonska et al. [36]	Sunlight	2012	(i) cross-sectional study (ii) Investigating whether rotating night shift working in nurses was associated with MD (iii) 640 nurses and midwives 40 to 60 years (iv) MD assessed by computer-assisted method	None
López et al. [19]	Physical inactivity	2003	(i) information collected from the Chicago Breast Health Project (ii) evaluation of association of hours of daily physical inactivity (iii) MD assessed quantitatively (iv) 294 Hispanic women	None*****
Suijkerbuijk et al. [37]	Physical inactivity	2006	(i) cross-sectional study (ii) 620 women 49 to 68 years, participants of the Dutch Prospect-European Prospective Investigation into Cancer and Nutrition cohort (iii) self-administered questionnaire about duration and intensity of physical activity (iv) MD assessed by computer-assisted system	None
Siozon et al. [38]	Recreational physical activity	2006	(i) 375 white and African American women (ii) Structured questionnaire obtaining data from 5 time periods of activity: menarche to 1st screening mammography, first 3 and 10 years after menarche, the most recent 10 years and the 3 years prior to mammogram screening	None
Samimi et al. [39]	Recent physical activity	2008	(i) cross-sectional study (ii) 1,398 women in the Nurses' Health Study (iii) three groupings: premenopausal, postmenopausal without HRT, postmenopausal currently under HRT (iv) MD assessed by computer-assisted method (v) prospectively collected questionnaires	None
Oestreicher et al. [40]	Physical activity	2008	Cohort of pre- and early perimenopausal women of 4 different ethnicities	Non-significant inverse
Woolcott et al. [41]	Aerobic exercise	2010	(i) inside the ALPHA trial: randomized controlled trial (ii) 320 postmenopausal, sedentary women 50 to 74 years (iii) randomized to 45 minutes, 5 days per week aerobic exercise or control with usual life-style for 1 year (iv) MD assessed by computer-assisted system	None
Conroy et al. [18]	Physical activity	2010	(i) using longitudinal data from 1996 to 2004 (ii) multiethnic cohort of 722 pre- and early perimenopausal women participating in the Study of Women's Health Across the Nation	None
Marmara et al. [42]	Last five years recreational physical activity	2011	(i) cross-sectional study (ii) 724 women 45–67 years (iii) interview-administered questionnaire (iv) MD classified according to BIRAD classification	Inverse
Qureshi et al. [43]	Physical activity	2012	(i) women data from the Norwegian Breast Cancer Screening Program (ii) MD assessed by computer-assisted system (iii) 2218 postmenopausal women 50–69 (iv) 13-page questionnaire	None******

*Pub yr: Publication year, **primarily dairy products, ***except for a cross-sectional inverse association at age 53 years in post-menopausal women, ****They showed that sunlight exposure in childhood is more effective, *****MD slightly higher when 3.5 hr physical inactivity per day, ******probable inverse association in overweight women.