Understanding colonoscopy: Why colonoscopy can save lives

The large intestine – an underestimated high-performance organ

The large intestine takes on far more tasks than many people think. It is around 1.2 to 1.5 meters long, consists of several sections, and has a muscle layer that rhythmically transports the intestinal contents onward. Its main task is the recovery of water and electrolytes, through which the remaining chyme becomes the final stool.
The gut microbiome also plays a crucial role: a bacterial community weighing about two kilograms that breaks down fiber, produces vitamins such as vitamin K and B12, trains the immune system, and protects the mucous membrane. If this ecosystem becomes unbalanced — for example due to stress, diet, or medication — digestion, immune defenses, and well-being are impaired.

Why the colonoscopy is so important

Colorectal cancer is one of the most common tumor diseases and usually develops slowly over years. The colonoscopy offers a decisive advantage: it not only allows a complete assessment of the large intestine, but also enables the removal of precursors such as polyps at the same time. It is precisely this combination that makes the examination so effective in prevention.
Screening is generally recommended from the age of 50, for women in some cases from 55, and then every seven to ten years. Those with a family history or who suffer from chronic inflammatory bowel diseases such as Crohn’s disease or ulcerative colitis should start earlier. The examination demonstrably reduces the risk of colorectal cancer — according to studies by up to 90%.

Preparation: The key to success

For the examination to provide clear images, the bowel must be completely cleaned. For this, a laxative solution is taken, which stimulates bowel movement and thoroughly rinses the entire large intestine with water. On the day before, light food should be chosen, while foods with seeds should be avoided.
Certain medications must also be paused — including iron supplements, certain blood thinners, diabetes medications, or diuretics. These adjustments serve safety and help prevent complications.

Examination procedure: precise, routine, and mostly in twilight sleep

The colonoscopy is often performed under sedation, which allows the examination to be experienced calmly and relaxed. The propofol used works quickly and wears off just as quickly, while the medical team continuously monitors vital signs.
The colonoscope itself is a highly advanced instrument with a camera, light source, irrigation and suction channel, as well as a working channel for instruments. While the insertion takes about 10–15 minutes, the actual diagnostics take place during the slow withdrawal. During this, the mucosal sections are carefully inspected, cleaned, and tissue samples taken if necessary.

Polyps: small growths with great risk — but easily treatable

Since polyps can develop over years, they can usually be removed well and early. For this, a wire loop is used that removes the polyp mechanically or with the help of an electrical impulse. Larger polyps are first padded with fluid to avoid injury. Only if a polyp cannot be completely removed or cancer is already present is surgery necessary.

Conclusion: Prevention that truly works

The colonoscopy is safe, effective, and offers the best opportunity to detect polyps in time and prevent colorectal cancer. Risks such as bleeding or injury to the intestinal wall are rare. Those who undergo the examination gain valuable reassurance — often for many years.