Is obesity in childhood protective for breast cancer in young women?

Islami et al. (1) reported the proportion and the type of cancers that are referable to excess of body weight (EBW) in United States. The study revealed 37,670 cancer cases in men and 74,690 cancer cases in women 30 years or older in US from 2011 to 2015 that could be ascribed to high body mass index. Interestingly, Islami et al. (1), found that the amount of population attributable fraction (PAF) for EBW was higher in women than in men, paralleling the close association between high body mass index (BMI) and increased risk for several female-specific cancers, such as breast cancer.