In 2012, 1.7 million cases of breast cancer were diagnosed across the globe, which makes up 25% of all cancer diagnoses in women.
There are several risk factors that increase a woman's likelihood of developing breast cancer. These include older age, early menarche, and having a family history of breast cancer.
The report consisted of an analysis of 119 existing studies that together examined the clinical data available on 12 million women, adding up to a total of 260,000 cases of breast cancer.
According to the report, as little as 10 grams of alcohol per day - the equivalent of a small glass of wine or beer - raises the risk of premenopausual breast cancer by 5%. The same amount of alcohol raises the risk of postmenopausal breast cancer - the most common form of breast cancer - by 9%.
Ten grams of alcohol amounts to less than the "standard" drink, which currently consists of 14 grams of alcohol.
Related Article: Dieting to Treat Cancer
Furthermore, the report confirmed that being overweight, having obesity, or just gaining more weight in adulthood increases the likelihood of postmenopausal breast cancer. Conversely, moderate exercise decreased the risk of both pre- and postmenopausal cancer.
Postmenopausal women who were the most active were 10% less likely to develop breast cancer compared with their least active counterparts. For premenopausal women, this drop in risk was 17%.