How your gut is influencing your health

When the intestinal flora is out of balance, a huge part of the body’s defense work doesn’t function anymore. This is because the intestine’s immune system protects us from bacteria, fungi, and other intruders. New research shows that intestinal disorders not only promote physical illness, but also affect the brain.

The human intestinal flora consists of nearly 1,000 different bacterial species – overall nearly 100 trillion bacteria. Everyone possesses their own individual intestinal flora that is influenced by nutrition and other immunological processes.

New research demonstrates that the composition of the intestinal flora has a considerable impact on the brain. Experts speak of the so-called “gut-brain axis” with which the interactions between the human intestinal flora and neurological disorders, such as multiple sclerosis, Alzheimer’s and Parkinson’s disease, can be detected. Depression can presumably also be linked to the intestinal flora.

Does depression develop in the intestines?

In a study, stool samples were taken from both depressed and healthy patients and injected into the intestines of rats. The result: the physiological equilibrium of intestinal bacteria changed in the rats that had received the “ill” stool. The animals developed depressive and anxious behavior.

Furthermore, the number of messengers, Tryptophan and Kynurenine, which are considered a contributory cause of depression, increased.

A lack of intestinal bacteria can lead to multiple sclerosis.

Studies have further ascertained that patients suffering from multiple sclerosis possess a lower diversity of intestinal bacteria than healthy people.

The reasons for this have not yet been detected. The decisive fact, however, is that bacteria normally produce short-chain fatty acids, the so-called propionic acid. These influence the immune cells in the brain, which are involved in the emergence and progression of multiple sclerosis. Immune cells only function immaculately when enough propionic acid is released from nourishment.

Further studies by researchers from Sweden and Switzerland have shown that links between intestinal germs and the immune system can both reinforce or reduce inflammation of the central nervous system.

In a study with mice, they found that an altered intestinal flora can cause Alzheimer's dementia.

Because of these results, researchers hope to develop new therapeutic approaches for the respective disorders, for example by means of new medicine based on propionic acid. Previous findings have shown an increase of immune cells by 30 percent and a considerable decrease of inflammation cells during the administration of these drugs. However, clinical outcomes are not yet available.

Cure through fecal bacteriotherapy (stool transplant)

Researchers work further on curing diseases by means of so-called fecal bacteriotherapy.

For this purpose, a small amount of foreign stool is injected into the intestine. New, healthy bacteria can thus settle in the intestine and moderately or even fully eliminate the disease.

This can either be carried out during a colonoscopy, by means of a nasal probe or – since very recently – through capsules. Donors are family members, as the intestinal flora usually is very similar. After a donation, the stool is specially prepared and filtered prior to administration.

Probiotic nutrition for a healthy intestine

A healthy intestinal flora can be reinforced with an appropriate diet, including probiotic foods (yogurt), food high in fiber and a lot of lactic acid (kefir, buttermilk, soured milk).

Nutrition beneficial for the intestine also includes a lot of fresh fruit and vegetables, grains, unsaturated fatty acids, vegetable fats and little sugar.