Dietary patterns, nutrition and risk of breast cancer: case control study in the west of Iran.

Objectives: Unhealthy dietary patterns are the most important changeable risk factors for breast cancer. The aim is to assess the relation between dietary patterns and risk of breast cancer among under 50 women in the west of Iran.

Methods: All under 50 years old women with positive pathology of breast cancer between 2013-2015 who were referred to the oncology clinics in the west of Iran were selected as the cases (212 persons) and 408 under 50 years old women referred to the other outpatient clinics who were without breast or other cancers at the time of study and two years later were selected as the control group. The data were collected using middle aged periodical care form of Iran Ministry of Health and analyzed using univariate and multivariate logistic regression in Stata.

Results: The most powerful risk factor for breast cancer was fried foods, so that the odds ratio of breast cancer in women consuming fried foods more than once a month was higher than women who have consumed it once or lower in a month (OR=4.5, CI 95% =2.1-9.4). Dose-response model indicated that increasing vegetables and fruits consumption up to 90 times a month decrease the odds of breast cancer, but more than 90 times a month can increase it.

Conclusion: Inadequate consumption of vegetables and consumption of soft drinks, industrial juices, fried foods and sweets are considered as risk factors for breast cancer. Sensitization, informing and education about healthy diets and change in unhealthy dietary patterns seem necessary.