It may be hard to think imagine, but our bodies our homes to billions of tiny organisms, and the greatest numbers reside in the gut. Our gut bacteria play an important role in nutrition and digestion, but recent research has also revealed the role it plays in other aspects of our health. According to a study from Lund University in Sweden, our intestinal bacteria can actually accelerate the progress of Alzheimer's disease, a finding that could lead to new prevention and treatment options.

The study, now published online in the journal Scientific Reports, found that mice who had Alzheimer's disease, but were bred to not have any gut bacteria, had significantly smaller amounts of beta-amyloid plaque in the brain. These buildups are a hallmark of Alzheimer's disease. The scientists also transferred intestinal bacteria from mice with Alzheimer’s disease to germ-free mice and found that these mice developed more beta-amyloid plaques in their brain than they would have if they received gut bacteria from donors without the disease. These results helped to solidify the idea that gut bacteria plays a role in Alzheimer’s acceleration.

Read: Autism Causes Update: The Gut-Brain Connection And How A Common Probiotic May Ease Symptoms

"The results mean that we can now begin researching ways to prevent the disease and delay the onset,” said researcher Frida Fåk Hållenius in a statement. “We consider this to be a major breakthrough as we used to only be able to give symptom-relieving antiretroviral drugs.”

Alzheimer’s disease is not the first condition to be linked to our gut bacteria. According to WebMD, the bacteria, viruses, and fungi living in our intestines, also known as our gut microbiota, help us with digestion and also make vitamins. In addition these microbes also send signals to our immune system and make small molecules that help our brains perform better. New research has begun to show just how indispensable these microbes really are and how many different aspects of our health they affect.

1. Autism

The idea of a link between autism and gut microbes is controversial, but some evidence does back this claim. For example, according to a 2017 Big Think YouTube video, the fecal samples from patients with autism contain a number of abnormalities, and closer examination of the gut microbiome of autistic individuals and those without the disorder show there are differences, although scientists have not yet been able to pinpoint exactly what these differences are, or better yet, what they mean. What’s more, a 2016 study even suggested that taking probiotics, which help boost the presence of healthy gut bacteria, could help to alleviate some autism symptoms.

2. Stress and Depression

We know that hunger can affect your mood, but some research suggests that our gut may actually control our emotions. The gut communicates to the brain in order to convey messages such as “we need more food” or “we’ve had enough food.” However, according to LabRoots, when there is an imbalance of helpful and harmful bacteria in our gut, this can lead to a number of mental health side effects such as anxiety, depression, and stress.

3. Migraines

A study published last year found that intense migraines may be due to abnormalities in gut bacteria. Some of these bacteria are extra sensitive to foods containing nitrates, and having more of these bacteria could trigger painful migraines when individuals eat foods high in nitrate. Foods more likely to trigger these effects include meats, leafy vegetables, and wine.

4. Parkinson’s Disease

Individuals with Parkinson’s disease often suffer from digestive issues, such as constipation, and there may be a reason for this. According to The Scientist, in mouse studies gut microbiota promote neuroinflammation and motor deficits in a mouse model of Parkinson’s disease. The study felt this showed that gut microbes not only contribute to mouse-Parkinson’s disease, but also play a role in its progression.

Source: Harach T, Marungruang N, Duthilleul N, et al. Reduction of Abeta amyloid pathology in APPPS1 transgenic mice in the absence of gut microbiota. Scientific Reports. 2017

See Also:

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Suffering Stress And Anxiety? Your Stomach May Be To Blame