BMI and Risk of Breast Cancer

Although a high childhood BMI may be protective against the risk of overall breast cancer, the mechanism is uncertain. The study team thereby analysed data of 173,373 women from the Copenhagen School Health Records Register born between 1930 and 1996 (aged 25 to 91 years now).

The information on height and weight was measured at annual school health examinations from ages 7 to 13 years. Cases of breast cancer were identified by linking with the Danish Cancer Registry.

It was found that girls with a higher body mass index (BMI) during childhood are less likely than their peers with a lower BMI to develop breast cancer as adults, both before and after menopause.

During an average of 33 years of follow-up, 4,051 women were diagnosed with breast cancer before menopause (at 55 years of age or younger), and 5,942 women after menopause (after age 55 years).

“Our results suggest that having a higher BMI during childhood may lower your risk of breast cancer both before and after the menopause. But we must be really clear that weight gain should not be considered as a way of preventing breast cancer. There are so many health risks linked with having overweight or obesity, it is vital for women to maintain a healthy weight throughout their lives”, says lead author Dr. Dorthe Pedersen from Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark.

The analyses suggest “inverse associations” between childhood BMI and breast cancer risk before and after menopause, which means that breast cancer risks decreased as BMI increased.

However further analysis is required to uncover the mechanisms underlying these associations.

Source: Medindia