Surprising: having Alzheimer's disease might protect against this cancer

Could certain diseases potentially protect us from other serious conditions? Researchers have just discovered a surprising link between Alzheimer's and colorectal cancer.


Chinese researchers have observed a surprising phenomenon: mice with cognitive disorders similar to Alzheimer's develop colon cancer less frequently.

To understand the cause, they analyzed the microbiota of these animals. They found high levels of certain gut bacteria, particularly Prevotella. These microbes seem to influence both cognitive health and cancer resistance.

The researchers transplanted feces from healthy mice into those affected by Alzheimer's. The result: these mice lost their protection against colorectal cancer, revealing the importance of the gut flora in this link.

Humans also show an inverse relationship between these diseases. People with Alzheimer's are less likely to develop certain cancers, and the reverse also seems to be true.

Scientists believe inflammation plays a key role in this correlation. Certain bacteria, like Prevotella, may modulate inflammation, thus reducing the risk of cancer while worsening cognitive disorders.

Previous studies had already shown that the gut microbiota influences brain health. These findings strengthen the idea that certain gut bacteria, through their byproducts, disrupt brain functions while offering protection against some cancers.

There is still a long way to go to confirm these discoveries in humans. However, this study opens up new perspectives for understanding how our intestines and brain interact.

Scientists hope that better knowledge of these mechanisms will lead to the development of innovative and more targeted treatments for neurodegenerative diseases and cancers.

The gut microbiota

The gut microbiota refers to the entirety of microorganisms living in our intestines. It includes billions of bacteria, fungi, viruses, and yeasts. These microorganisms play an important role in digestion, metabolism, and the proper functioning of the immune system.

The gut microbiota communicates with the brain via the gut-brain axis. The bacteria present in our intestines produce substances that influence the production of neurotransmitters like serotonin, which is essential for mood regulation and cognitive functions.

Studies show that imbalances in the microbiota, called dysbioses, can contribute to the development of neurodegenerative diseases like Alzheimer's. Certain bacteria, such as Prevotella, produce inflammatory substances that may aggravate cognitive disorders by altering the intestinal barrier and promoting systemic inflammation.