Skinny girls at higher risk of breast cancer

Researchers at the Karolinska Institute in Stockholm found that girls underweight at the age of seven are more likely to develop aggressive types of tumours which are very difficult to treat  than those who are larger in size.

The study also showed that larger girls were less likely to develop what are known as “oestrogen receptor negative” tumours, one of the most deadly forms of the disease. “It appears counterintuitive that a large body size during childhood can reduce breast cancer risk, because a large birth weight and a high adult BMI have been shown to otherwise elevate breast cancer risk,” lead author Jingmei Li said.

“There remain unanswered questions on mechanisms driving this protective effect,” she said, adding “given the strength of the associations,  childhood body size is potentially useful for building breast cancer risk or prognosis models”.