Bigger brains increase cancer risk?

According to the findings of a recent study, bigger brains are associated with greater risk of cancer.

The Norwegian University of Science and Technology (NTNU) study has been published in the journal Neuro-Oncology.

"Aggressive brain cancer is a rare type of cancer, but once you have it, the chance of survival is relatively low," researcher Even Hovig Fyllingen said.

-Lifestyle matters less

For some types of cancer, lifestyle makes a big difference. People who smoke have a greater risk of lung cancer than non-smokers, for example. A person's lifestyle matters less for brain tumour development.

A large brain means more brain cells. And the more cells you have, the more cell divisions that can go wrong and create mutations that lead to cancer.

-Big organs, bigger risk

"Several studies have shown that the size of different organs is an important factor in cancer development. For example, women with larger breasts have a greater risk of breast cancer. We wanted to check if this was also the case for brain tumors," said Fyllingen.

-Mostly men who get brain tumors

The study also shows that more men than women develop brain tumours.

"Men have a larger brain than women because men's bodies are generally larger. It doesn't mean that men are smarter, but you need to have more brain cells to control a large body. This is also the case with animals. In bigger bodies, organs like the heart, lungs and brain are also bigger," said Fyllingen.

Yet it turns out that women with big brains have a greater risk of developing brain tumors compared to men with big brains.

"Seventy per cent more men than women develop brain tumours, but when we correct for head size, it's no longer beneficial to be female. Women with large brains are particularly susceptible. Why that is I have no idea," said Fyllingen.