Gut Microbiome and Alzheimer’s Disease

You may wonder what the gut has to do with a disease that has to do with the brain, but Alzheimer’s disease has been puzzled scientists to find the cause – emerging information may prove important to treat it.  The microbiome in our gut is a collection of microbes that have an impact on our body functions particularly our gastrointestinal and immune health – however research is showing it has greater participation in many other body systems.

What is Alzheimer’s disease?

While research has not discovered a single cause for Alzheimer’s disease, some factors are identified as risks. Alzheimer’s disease is a progressive neurodegenerative disease that is a type of od dementia affecting memory, behavior, and thinking.  As symptoms progressively worsen – people with Alzheimer’s find it difficult to do daily tasks. While dementia may seem like a normal part of the aging process, Alzheimer’s is not.  60-80% of dementia patients is caused by Alzheimer’s – affecting mostly people age 65% and older – 32% are age 80 or older.  Also, people under 65 (approx. 200,000 Americans) have an early onset of Alzheimer’s disease. This is not just a disease of the elderly.

Risk factors

• Age
• Family history
• Genetics
• Head injury
• Heart health and brain health link

Symptoms of Alzheimer’s

• Difficulty remembering newly learned information
• Disorientation
• Mood and behavior changes
• Deepening confusion about events, time, and place
• Struggles with routine tasks such as planning, cooking, and dressing
• Unfounded suspicions about family, friends, and professional caregivers
• Ability to make decisions decline
• Repeats statements and questions over and over
• Forgets conversations, appointments, events
• Misplaces things
• Gets lost in familiar places
• Forgets the names of everyday objects and family members
• Serious memory loss
• Difficulty speaking, swallowing, and walking
• Social withdrawal
• Mood swings, depression, irritability, and aggressiveness
• Sleeping habit changes

The brain and Alzheimer’s disease

Some of the common changes in the brain that scientists believe are part of Alzheimer’s is that it prevents the brain cells from working properly.  Eventually, this can cause issues and certain cells lose their ability to function, die and this causes permanent damage within the brain.

Secondly, people with abnormal structures or misfolded proteins in their brain as they age are known as the following:

• Plaques – deposits of beta-amyloid or protein fragment that builds up between the nerve cells in the brain.
• Tangles – tau fibers that are twisted and build up inside the cells.

While these are present in those with memory issues caused by Alzheimer’s, scientists are still unsure of the role they play.

Overall, scientists believe that Alzheimer’s disease is caused by multiple factors including genetic, lifestyle, and environmental that affect the brain – recently this included the microbiome. Lifestyle choices such as poor sleep patterns, lack of exercise, obesity, smoking, high cholesterol, high blood pressure, and uncontrolled type 2 diabetes are all risk factors.

What is Gut Microbiome?

The gut microbiome consists of trillions of microorganisms, along with their genetic material. These microorganisms live in our intestinal tract and are responsible for helping to absorb and synthesize nutrients and play an important role in how we digest the food we eat. Also, these gut microbiota play roles in many other functions of the body, including metabolism, immune regulation, cognitive function, and mood.

Everyone has a fingerprint unique to themselves and everyone has a gut microbiome that is a bacterial fingerprint. Scientists are still researching what a healthy gut microbiome is, but they have become aware that it is a safety net of sorts. When we have a healthy gut, it keeps things that don’t belong in the bloodstream out, such as undigested food particles, toxins, and microbiota. A healthy gut also helps to fight off infection.

What scientists do know is the diversity of bacteria in the gut is good. This allows different types of good bacteria that can help to fight off bad bacteria:

• Good bacteria – also known as beneficial bacteria, is any bacteria that enhance overall health. Probiotics are an example of good bacteria.
• Bad bacteria – are harmful to our body and usually cause us to be sick. Some bad bacteria can spoil your food or create an unhygienic environment.

However, as with many health functions, balance is key, having about 85% good bacteria and 15% bad bacteria is a good balance for our gut microbiome. Bacteria are needed to break down carbohydrates or sugars, toxins, and help our body absorb fatty acids so our cells can grow.

Alzheimer’s disease and links with gut microbiome

According to a journal article in Frontiers in Cellular and Infection Microbiology, “Significant quantitative and qualitative changes of the gut microbiome have been reported in patients with Alzheimer’s disease.”  Since the gut microbiome can be affected by negative external lifestyle habits – it should be taken into account for those developing Alzheimer’s.  These include a sedentary life, chronic noise, circadian rhythm disturbance, sleep deprivation, and dietary choices that do not benefit the gut microbiome.

Also, the gut microbiome plays a crucial role in the central nervous system and is known as the “brain-gut microbiota axis”  The interaction between the gut and the brain links the digestive, immunity, and nervous system in turn the intestinal microbiome influences the brain functions.

Causes of Intestinal dysbiosis or imbalances in the microbiome

• Changes in the diet
• Non-steroidal anti-inflammatory drugs
• Pathogenic microorganisms
• Acute stress
• Infection caused by pathogenic bacteria particularly Citrobacter rodentium
• Disruption of the intestinal and blood-brain barrier
• Poorly diversified microbiota
• Oral microbiome and Alzheimer’s

Is there a link between the gums and the brain?

The pathogen found in chronic periodontitis or Porphyromonas gingivalis has been identified in the brain of Alzheimer’s patients.  The bacterium gingipains contained toxic proteases also found in their brains.  Because those with Alzheimer’s have neuroinflammation that is more often correlated with infection – it seems that infectious agents may be the cause – although evidence has not been established.

However, the tau protein has been linked to a gingipain load in the brain, correlating with Alzheimer’s disease diagnosis – however, more research is being done to discover the role this plays in the disease.

Reduce the risk of Alzheimer’s and Improve Your Gut Microbiome

Regular physical activity

A sedentary lifestyle has been a risk factor – spend time doing moderate aerobic activity, walking, riding a bike, digging in the garden, or playing a sport.

Eat a healthy diet

A Mediterranean diet that includes fruits, vegetables, legumes, whole grains, fish, and olive oil as the primary fat.

Keep learning

Exercise your brain by keeping it active – life long learning, memory skill games, and cognitive skill puzzles.

Reduce stress

If you are chronically stressed, this will affect your gut. Great stress busters include meditation, exercise, and anything that relaxes you.

Sleep

Make sure you get at least 7 to 8 hours of sleep per night because low quality sleep or too little sleep can impact your gut health.  It has been found that your microbial ecosystem can affect your body’s sleep wake-sleep cycle and the hormones that help your body to regulate sleep.  Research has also shown that an imbalanced microbiome can increase how sensitive someone is to visceral pain, making it more difficult to fall asleep and stay asleep.

Change your diet

• Reduce the amount of processed, sugary, and high-fat foods that are so common in the “Western diet”
• Quit smoking
• Smoking can be a higher risk of developing dementia

Fermented foods for gut health

Foods such as yogurt, kefir, tempeh, miso, kimchi, and sauerkraut are a great source of probiotics.

Prebiotics and Probiotics

An excellent way to improve gut health is to take a prebiotic or probiotic supplement daily.

Collagen for gut health

Collagen rich foods include salmon and bone broth. Also, foods such as mushrooms, some dairy, and meats can help your body boost its collagen production. You can also take a collagen supplement and add it to your morning coffee or smoothie.

L-Glutamine for gut microbiome

L-glutamine is a gut-healing amino acid, known to support a strong intestinal barrier, reduce intestinal permeability, support normal immune function, and reduce the inflammatory response.

Supplements for Alzheimer’s

• Ginkgo biloba
• Omega-3 fatty acids
• Vitamin E
• Curcumin
• Vitamin B