Fluid milk intake may be in decline, but recent academic findings have reaffirmed the dairy staple’s beneficial role for gut health health and wellbeing.
The study, led by University of Oxford scholars, supports previous academic research into calcium-rich products’ ability to decrease the risk of colorectal cancer.
But the new study’s findings are also larger in magnitude than previous research in this field; though it’s possible that the exact association between milk intake and colorectal cancer differs among populations that cannot digest lactose, such as China, the researchers stated.
How much milk is enough to decrease the risk of cancer?
The role of milk in bowel cancer prevention is likely down to calcium content, the study found.
According to the findings, consuming less than one glass of milk (200ml/7fl oz) per day already reduces the risk of cancer by 14%; while a glass’ worth (244ml / 8.6fl oz) decreases it by 17%, thanks to increasing calcium levels to 300mg.
To obtain the data, the researchers analyzed genetic data from more than half a million women to see how the ability to digest lactose influenced changes in DNA; and also looked at dietary information from participants, such as their milk intake.
The protective role of calcium
As for why calcium protects from cancer, the researchers theorized that this could be down to calcium’s ability to bind to bile acids and free fatty acids in the colonic lumen; protecting the intestinal mucosa from being impacted by bile acids. Additional research is needed to investigate how calcium supplements may impact bowel cancer risk or assess the general health risks of consuming too much calcium.
Bad news for meat, alcohol
While the study proved milk intake’s positive role in reducing the risk of colorectal cancer, it also confirmed some hard truths - that alcohol and red and processed meat are known contributors to cancer risk.
Having examined nearly 100 dietary factors, the researchers found that alcohol and calcium had the strongest associations with colorectal cancer risk – with a positive association for alcohol and negative for calcium. In fact, around 20ml of alcohol per day increases cancer risk by around 15%, according to the paper.
Red and processed meat were also strongly linked to increasing the risk of the disease, with 100g of meat per day raising the risk of cancer by more than a quarter (29%).
Source:
Papier, K., Bradbury, K.E., Balkwill, A. et al. Diet-wide analyses for risk of colorectal cancer: prospective study of 12,251 incident cases among 542,778 women in the UK. Nat Commun 16, 375 (2025). https://doi.org/10.1038/s41467-024-55219-5