Reacción a "Study confirms that a higher body mass index in childhood is linked with lower risk of breast cancer"

This study reveals that a high BMI in nulliparous women between menarche and age 40 reduces the risk of breast cancer, with protective effects that diminish when adjusted for prepubertal adiposity. These results seem to support the idea that obesity at an early age does not have the same harmful effect as it does in adulthood and, above all, during menopause.

The large sample of 56,863 women and the methodology used (albeit with its limitations) confirm that there is a critical window at an early age when breast cancer prevention can be applied, highlighting the genetic influence of BMI in the early reproductive stages. However, these results must be taken into consideration due to genetic variability and possible biases in BMI.

Nevertheless, I believe that recommending “young women to gain weight” to avoid this tumour should be taken with great caution. In any case, it does tell us that breast cancer has multiple factors to consider and that fat as an endocrine organ does not seem to be the same depending on age and menopausal status, and that this effect seems to be somewhat more pronounced in RE+ [oestrogen receptor-positive] tumours.