When you think about preventing colorectal cancer - the second most common cancer in developed countries, and one of the biggest killers of people over 50 - the first impulse is to run to the pharmacy and buy expensive supplements. Dr. María Carmen Riesco, an oncologist at Madrid's 12 de Octubre hospital, says exactly the opposite: "To date there's no scientific proof that any tea, infusion or supplement reduces the risk."

The six habits she recommends are simple, free and inconvenient for the supplements industry. First: a diet rich in fibre. Fruit, vegetables, whole grains - they help with bowel transit and feed a healthy microbiome. At the same time, limit red and ultra-processed food.

Second: regular exercise. Physical activity not only reduces the risk of a first tumour, but also the chance of recurrence in patients who have already been treated. Third: avoid tobacco and alcohol - both directly raise the odds.

Fourth, screening. After 50, faecal occult blood tests every two years, or a colonoscopy every ten years if there are no relevant findings. Fifth, warning signs: persistent changes in bowel habits, blood in stool, abdominal pain, unexplained weight loss, anaemia - all of them mean see a doctor, not self-medicate.

And sixth, the most important - forget the "miracle" supplements. The marketing of "natural gut remedies" is a huge industry built on the fact that people don't want to change their everyday habits. But it's exactly those habits, not the pills, that make the difference. The Balkan mother who keeps asking "what can I drink for it?" for her health might need to hear that the answer is to eat beans with kale, to walk, and to go for a colonoscopy on time.