Eating green leafy vegetables such as kale, cabbage as well as broccoli could help maintain a healthy gut and prevent colon cancer, says a new study.
The findings revealed that mice fed on a diet rich in indole-3-carbinol (I3C) — which is produced when we digest these vegetables — were protected from gut inflammation and colon cancer as it activates a protein called the aryl hydrocarbon receptor (AhR).
AhR acts as an environmental sensor, passing signals to immune cells and epithelial cells in the gut lining to protect us from inflammatory responses to the trillions of bacteria that live in the gut.
In the study, published in the journal Immunity, when genetically modified mice — that cannot produce or activate AhR in their guts — were fed a diet enriched with I3C, they did not develop inflammation or cancer.
But “when mice whose cancer was already developing were switched to the I3C-enriched diet, they ended up with significantly fewer tumours which were also more benign,” said lead author Amina Metidji from the Francis Crick Institute in the UK.
Moreover, the team found that normal mice fed on standard or I3C-enriched food did not develop tumours, while those fed on a ‘purified control diet’ developed colon tumours within 10 weeks.
Purified control diets contain exact mixtures of carbohydrates, proteins, fats and fibres enriched with vitamins and minerals, but have fewer AhR-promoting chemicals.
“This suggests that even without genetic risk factors, a diet devoid of vegetable matter can lead to colon cancer,” the researchers noted.
The study shows that while we cannot “change the genetic factors that increase our risk of cancer, we can probably mitigate these risks by adopting an appropriate diet with plenty of vegetables”.