October 3, 2018

expert reaction to study looking at diet and the breast microbiome in non-human primates

Research published in Cell Reports suggests that diet plays a role in determining microbiota populations in the mammary gland which may be linked to the likelihood of developing breast cancer.

Prof Paul Pharoah, Professor of Cancer Epidemiology, University of Cambridge, said:

“The press release states that “Breast cancer risk in women is increased by consumption of a high-fat Western diet full of sweets and processed foods but reduced by a healthy Mediterranean diet consisting of vegetables, fish, and olive oil.”  It would be more accurate to state that “Breast cancer risk in women is associated with a high-fat Western diet…” because there is little good evidence that this association is causal.

“The researchers show that changing the diet of macaque monkeys changes the types of bacteria that are normally present in the breast tissue – the breast microbiome.  This might also be true in humans, though there are no data to confirm this.  Moreover, there are no data to show whether or not the make-up of the breast microbiome has any relevance to breast health and disease.

“In summary, this is a moderately interesting scientific finding, but one that has minimal direct relevance to human health.”

* ‘Consumption of Mediterranean versus Western Diet Leads to Distinct Mammary Gland Microbiome Populations’ by Carol Shively et al. was  published in Cell Reports at 16:00 UK time on Tuesday 2^nd October.

Declared interests

Prof Paul Pharoah: No conflicts of interest