Contributor: Jamie Foti
The majority of disease begins in the gut, and new research indicates that chronic brain diseases like Alzheimer’s Disease are no exception. While it’s definitely too early for researchers to fully explain the exact relationship between the gut and risk of neurodegenerative diseases, there is a lot of fascinating research being published. It becoming more and more clear that your gut is directly involved in regulating brain function. In this article, I’m going to explain why targeting your gut bacteria to prevent Alzheimer’s Disease may be beneficial, in addition to how you can heal your amazing gut-brain axis.
Your Second Brain
But let’s start with some basic information: The gut is commonly known as the second brain. Have you heard that term used? It describes the constant messages that are sent both from the gut to the brain and from the brain to the gut. At one time, researchers believed that conditions like dementia or depression occurred solely in the brain however, new research continues to identify the deep interconnectedness of the gut-brain axis. The vagus nerve connects the Central Nervous System (CNS) in the brain, specifically the hypothalamic-pituitary-adrenal axis (HPA axis) and the enteric nervous system in the gut (think of this as a web of hundreds of millions of neurons that control the function of your GI tract). Inputs from the CNS can modify the function of the gut and inputs from the gut can impact the function of the CNS. When the communication system is altered or a person’s gut is altered, it may lead to the onset of neuroinflammation, which is a contributor to Alzheimer’s Disease. Now it’s important to note that there are other variables that are closely associated with increasing risk of Alzheimer’s Disease such as genetics and Type 2 Diabetes. We will dive into the genetics side of ApoE4 in a future article.
5.8 Million Americans are Living with Alzheimer’s in 2019
The gut-brain axis is an incredibly important breakthrough in our understanding of the human body given that the incidence of dementia and Alzheimer’s Disease have been rising dramatically. And the craziest part is that none of the pharmacologic medications available today can slow or stop the destruction of neurons that cause the onset of symptoms. According to the Alzheimer’s Association, it’s estimated that 5.8 million Americans living with Alzheimer’s Disease in 2019.The number of new cases of Alzheimer’s Disease between now and 2050 are expected to double. Just between 2000 and 2017, deaths from Alzheimer’s Disease have increased by 145%.
The profound thing about Alzheimer’s Disease is that 20 years before symptoms appear, the brain changes of Alzheimer’s Disease may begin. What does that tell us? It’s important to take charge of your lifestyle now in order to decrease risk of neurodegeneration and improve your overall cognitive function.
Your Gut is the Epi-Center of your Brain
Due to the powerful role that the gut plays on so many areas of the body, it is truly the epi-center of your brain health. Incase you didn’t know yet, the gut microbiome is a collection of trillions of powerful microbes that line the digestive tract, housing many different strains of bacteria. It influences nearly every process in the body. An observational study conducted in 2019 analyzed the stool of 128 dementia and non-dementia patients and they found very significant differences between the two. While this does not prove cause and effect, certain findings like lower levels of bacteroides (a beneficial bacteria that lives in the intestines) in dementia patients may indicate that gut bacteria could be the future target for preventing dementia and Alzheimer’s Disease.
An astounding study recently conducted in mice who were prone to developing Alzheimer’s Disease really helped with understanding the connection. While human studies are always better than animal studies, you have to start somewhere with the research. Some of the mice were given a broad-spectrum antibiotic to wipe out the gut microbiome. The mice that received the antibiotics had a reported two-fold decrease in amyloid beta peptides in the brain. These are the plaques that build up and are associated with the onset of Alzheimer’s Disease. Talk about fascinating! What it means is that there is some kind of interaction happening between the microbes in the gut and the brain which can lead to the development of the plaques, at least in mice. The researchers did not identify one specific strain of bacteria that is directly associated with an increased risk of Alzheimer’s Disease. They started with asking a broader question of whether alterations in the gut impact the brain. And the answer was, definitely yes.
There are a lot of things that you can do to improve the health of your bugs and lower risk of cognitive decline. Read below for my top tips on keeping your microbiome and brain in tip-top shape.
10 Tips to Heal your Gut Brain Axis
1. Learn to Manage your Stress Because Stress Shrinks the Brain
This may be the most important takeaway of the entire article! The relationship between stress and the microbiome is self-perpetuating. Stress determines the bacteria that thrive within your microbiome and the bacteria within your microbiome determine how reactive your nervous system is to stress. The more stressed you become, the more imbalance that can occur between various microbe populations. A 2014 study conducted in mice even demonstrated that just a short 2-hour stressor significantly altered the composition of the microbiome and decreased the abundance of two beneficial strains, L.reuteri and Lactobacillus.
This makes you even more reactive to small stressors which, in turn, has been shown to damage the balance of bacteria. A 2016 study showed that stress induces changes in the microbiome that reduces both the richness and diversity of bacteria, key components to gut health. The reduced diversity dampens the production of beneficial short chain fatty acids and neurotransmitter synthesis, directly affecting brain health and mood. It is crucial that neurotransmitter production is supported, since 90% of the “feel good” neurotransmitters, dopamine and serotonin, are made in the gut and taken to your brain through the vagus nerve. The vagus nerve is also directly involved in the autonomic nervous system –aka your parasympathetic (rest and digest) and sympathetic (fight or flight) systems.
Because stress affects the microbiome, vagus nerve and HPA axis in so many ways, protect yourself from unnecessary stress and drama. As for the stress that you can’t unplug from, I would strongly recommend beginning a 5-10-minute daily meditation practice. The beauty of a meditation practice is that it trains the brain to make you less reactive to stress. Just practicing for a few minutes a day can improve your brain health.
2. Limit Stripped Carbohydrates and Added Sugars
The bacteria in your gut survive off of the carbohydrates that you consume, and just like you, their health depends on the quality of those carbohydrates. Consuming excess refined carbohydrates (ie: white rice, white pasta, white bread, white flour) and simple sugars (ie: brown sugar, cane sugar, coconut nectar, agave nectar, maple syrup, high fructose corn syrup, etc.) fuels an imbalanced gut and increases risk of potentially pathogenic bacteria and candida growing at rapid rates and throwing a party throughout your entire colon.
These carbohydrates can also wreak havoc on your blood sugar. Researchers are finding a connection between foods that increase your blood sugar and thus, production of insulin and many neurological conditions. Even Alzheimer’s Disease is often referred to as “Type 3 Diabetes”, since its development and progression is so closely linked to high blood sugar and insulin production. As a side note: Type 2 Diabetes is actually a very common risk factor for Alzheimer’s Disease.
3. Limit Gluten, Alcohol & Pesticides
Leaky gut is when the lining of your gut develops holes and allows particles to enter the bloodstream and stimulate inflammatory conditions. And a leaky gut can lead to a leaky brain. The major offenders responsible for creating leaky gut are gluten, alcohol, and pesticides. In a 2015 study, gluten consumption contributed to a leaky gut, even in those without a gluten sensitivity. What does the mean? If you can tolerate gluten in your diet, don’t go crazy. Not everyone needs to be 110% gluten-free but most people will benefit from a low or no gluten diet.
Limit your alcohol consumption, aiming for having one to two glasses 2-3 times per week, and avoid foods sprayed with common chemicals such as glyphosate. Glyphosate is found on a number of foods but most commonly in soybeans, corn, wheat, and oats. I’m sure that you saw the story about glyphosate in Cheerios. This is why it’s beneficial to purchase organic whenever possible.
4. Talk to your Doctor about Avoiding Unnecessary Antibiotics
Antibiotics are extremely powerful drugs and, if taken at the right time, can be life-saving. However, antibiotics are currently extremely over-prescribed with some doctors prescribing them for viral conditions that aren’t even affected by antibiotic drugs. Along with killing off the harmful bacteria, antibiotics kills the good guys too, effectively wiping out lots of bugs that you need. It’s best to make sure that an antibiotic is 100% necessary and if so, take a probiotic two hours after treatment to restore the population of bacteria in your gut.
5. Listen to your Gut
One of the most powerful things that you can do for your gut and your brain is listen. Your gut is able to process feelings that your brain cannot. This is called your intuition and having a healthy gut and improved mental clarity requires listening to your intuition. When you don’t listen to your gut, your body can feel betrayed. This can actually lead to the manifestation of abdominal bloating, constipation, and other GI symptoms that can also affect your production of neurotransmitters and messages that are sent to your brain. Take time to sit with yourself in quiet and listen to the signals that you receive. The more that you go inward, the more peace and clarity you will find.
6. Load Up on Wild Salmon
Alzheimer’s Disease is considered a neuroinflammatory disease—meaning inflammation is a common underlying root cause. And if you have an inflamed gut then you would be more prone to having an inflamed brain. Omega 3 fatty acids found mostly in certain fish and/or supplements can increase friendly bacteria and short chain fatty acids in the gut while also lowering inflammatory markers such as TNF-alpha and IL-6. When a person does not have enough omega 3s in their diet it can increase unfriendly bacteria and increase risk of leaky gut. By creating a healthier environment in the gut, omega 3s may improve cognitive function and play a role in lowering neuroinflammation.
Aim for at least three servings of low mercury, high omega 3 fish per week. This could include wild salmon, sardines, mackerel, herring, rainbow trout, and oysters. You may also need additional supplementation.
7. Add 3 Colors with Every Meal
Color in food means phytochemicals, the bioactive plant substances that provide your body with beneficial compounds. Phytochemicals—namely polyphenols—are another source of fuel for the bacteria, and as they digest these polyphenols, they release compounds that fuel your body. A diverse range of color in the diet means that you get a diverse range of phytochemicals which, as you guessed, feeds a diverse range of species of bacteria. Having high diversity in the gut is one of the main signs of a healthy microbiome and can increase resiliency within the gut barrier. So, aim for three colors with each meal that you eat!
8. Incorporate Fermented Foods & Fermentable Fibers
Eating fermented foods directly feed beneficial bacteria in the gut—similar to a probiotic. Examples of these foods include sauerkraut, kimchi, organic yogurt, almond yogurt, coconut yogurt, organic kefir, pickles, organic tempeh, and apple cider vinegar. You may also benefit from a high quality probiotic. In a double-blind randomized control trial, individuals with Alzheimer’s Disease who were given 12 weeks of daily probiotic supplementation–including lactobacillus and Bifidobacterium– improved on their mini-mental state examination. This was the first study to demonstrate an association with the use of probiotics and outcomes for Alzheimer’s patients.
The main fuel source for your beneficial bacteria is fiber. Low fiber diets prevent the growth of the cool bugs in your intestines and can lead to low diversity of bacteria—which is basically like having a dying off forest. Researchers are beginning to identify that a diet high in prebiotic and probiotic foods may help reduce the level of chronic inflammation and amyloid beta levels associated with Alzheimer’s disease. Many of these fibers are called prebiotic, since they feed the bacteria in your large intestine. The bacteria ferment these fibers in your large intestine, fueling themselves and a number of benefits supported in research. Examples of prebiotic-rich foods to load up on are chicory root, dandelion greens, jerusalem artichokes, onions, leeks, asparagus, green bananas, apples and flaxseeds.
9. Try Intermittent Fasting for 12-16 Hours
Intermittent fasting has influenced brain aging and neurodegeneration in rodent models. Leading neurologists such as Dr. Dale Bredesen incorporate fasting into protocols for Alzheimer’s Disease patients. One of the main reasons that people notice cognitive improvements is because fasting increases insulin sensitivity. Insulin is a pro-inflammatory, fat-storing hormone that is associated with brain damage.
A second reason is that intermittent fasting boosts levels of Neurotropic Factors called Brain Derived Neurotropic Factor (BDNF). Neurotropic factors are molecules that repair damaged neurons and have been associated with the prevention of neurodegenerative disease. A 2017 study assessed individuals that participated in the Muslim holy month of fasting, Ramadan. Individuals that participate in Ramadan abstain from eating from sunrise to sunset. Compared to the control group, individuals that fasted throughout the month of Ramadan experienced 25-47% higher levels of BDNF.
Though fasting may seem daunting, simply ending dinner by 8 PM and picking up eating again at 8 AM could be enough to see these benefits. Women should be cautious of going 14-16 hours of fasting regularly without working with a dietitian or knowledgeable healthcare practitioner.
10. Prioritize Excellent Quality Sleep
Getting a good night sleep is so critical for your diversity of bugs in your gut and also for your brain. Getting a full night of restorative sleep is similar to making it all the way to the end of the car wash without hitting the gas—basically necessary unless you want to be soapy! This is relevant because sleeping at night is like sending your car through the car wash to get clean. A small study found that just one night of lost sleep led to an increase in amyloid beta proteins. That was just one night! Researchers believe that chronic sleep deprivation may lead to an increased risk of amyloid beta build up. Not good!
Aim for 7-8 hours per night. If you need additional tips read the Best Tips for Improving your Sleep.
There you have it! The sooner that you can incorporate some of these tips, the faster you will start healing your gut-brain axis and approaching your health from a preventative lens!