“All disease begins in the gut.”
The connection between the gut and the brain has been studied for hundreds of years. But, in modern medicine, that connection has for the most part been misunderstood. The traditional (old) way of looking at chronic illness was that trauma causes PTSD and other psychological symptoms and therefore, chronic illness must be psychological too. The belief that psychological symptoms are the only effects of trauma is not true (Mead, 2018). Emerging science is discovering the link between early childhood trauma and the health of the microbiome (the gut). We now know that at least 80% of serotonin is in our gut and most of our immune system is in our gut. What does this mean? The gut-brain axis refers to the physical and chemical connection between the gut and the brain. Neurotransmitters are found both in the brain and the gut and they influence each other’s actions. The gut contains trillions of microbes that make chemicals such as gamma-aminobutyric acid (GABA), a neurotransmitter that helps control fear and anxiety and short-chain fatty acids (SCFA) such as butyrate, propionate and acetate which are made from digesting fiber (Robertson, 2018).
At least 90% of chronic and autoimmune diseases are caused by alterations in the gut microbiome. Childhood trauma can alter gut bacteria by altering the function of the nervous system, how our genes function, and shorten our telomeres leading to lack of longevity (Mead, 2018). When trauma alters our nervous system, it changes our physiology, emotions, behaviors, and thoughts (Mead, 2018). This is where chronic illness and autoimmune disease come to life. Standard treatments are medications like antidepressants for mood disorders and different pharmaceuticals to treat symptoms of chronic illness without looking at the root cause. These types of treatments are costly, come with an array of side effects and adding to the stress the patient is already experiencing in their life. Growing science and research are proving that childhood trauma leads to various health conditions later in life.
Adverse Childhood Experiences (ACE) is a study developed by a physician and researcher, Vincent J. Felitti, MD, an internist for Kaiser Permanente Medical Program in San Diego and an epidemiologist from the CDC, Robert Anda, MD. ACE is a survey that uses a scoring system from 0 to 10 that indicates 10 types of childhood traumatic experiences. They are:
Mother Treated Violently
Substance Abuse (drugs/alcohol)
Parental Separation or Divorce
Incarcerated Household Member
According to the CDC, 61% of adults have experienced 1 or more ACE and 16% experienced at least 4 types of ACE (1 in 6 adults have a score of 4 or more). Another startling statistic is that at least 5 of the top 10 leading causes of death are associated with ACE. (CDC, 2019))
The purpose of this research is to uncover how the gut and the brain are connected and how this connection influences our diet and lifestyle choices and how those choices can alter our gut.
The microbiome is composed of bacteria, bacteriophage, fungi, protozoa and viruses (genome.gov). There are more microbial cells in the human body than there are human cells; about 10 times more. Meaning that we are more bacteria than we are human. A healthy microbiome is diverse and is responsible for: digesting food to generate nutrients for host cells, synthesizing vitamins, metabolizing drugs, detoxifying carcinogens, stimulating the renewal of cells in the gut lining and activating and supporting the immune system. (genome.gov) It is where 80% of the body’s immune system lives. The health of the microbiome determines how the gut and the brain communicate with each other.
The bacteria that the microbiome houses are determined by factors like stress, life experiences, toxins, diet and lifestyle practices. Early life experiences, like trauma disrupts our health as the microbiome plays a major role in the immune system, hypothalamic-pituitary-adrenal (HPA) axis, and in recent studies, contributes to psychiatric disorders such as PTSD. The HPA axis is the body’s stress management system and regulates various body functions like digestion, immune system, endocrine function, and mood. “Social and psychological stresses activate the HPA axis, which results in increased corticotropin-releasing hormone (CRH) levels in the cerebrospinal fluid. PTSD is hypothesized to reflect a sustained stress response.” (Leclercq, Forsythe, & Bienenstock, 2016) This puts the body in a constant fight, flight, or freeze mode. This constant state of being can overwhelm the body’s nervous system causing our neurotransmitters to malfunction which can lead to a vast number of symptoms like leaky gut, inflammation, and mood disorders. Being in a stressed state, especially a chronic state, the stress changes your physiology and can disrupt the digestion process (from eating/chewing to elimination and nutrient absorption).
Trauma alters gene function through epigenetics. Epigenetics is “how our genes can adapt to changes in the environment even though the actual structure of the genome - the genes themselves - don’t change.” (Borysenko, 2017) In addition, stress caused by childhood trauma can shorten our telomeres (the areas at the end of chromosomes that protect our genes from destruction). Shorter telomeres are linked to shorter lifespan. ACE statistic shows that those who have a score of 6 or more, shorten their life span by 20 years. (Nakazawa, 2015) Furthermore, those who scored a 7 or higher who didn’t smoke, drink, weren’t overweight, diabetic, and didn’t have high cholesterol still had a 360% higher risk of heart disease than those with an ACE score of zero. “The chronic stress of emotional and physical adversity these adults had experienced when they were growing up was making them ill decades later—even though they had healthy habits and lifestyles.” (Nakazawa, 2015) According to Dr. Mead, childhood trauma can result in poor gut health that can lead to the following and more:
Alcohol and/or drug dependence
Diabetes (Types 1 & 2)
PTSD (post-traumatic stress disorder)
Behavioral problems (risky and unhealthy)
Irritable bowel syndrome
Inflammatory bowel disease
Chronic fatigue syndrome
Celiac Disease/gluten sensitivity
“Gut bacteria also influence the biology and function of the brain through the production of hormones or neurotransmitters, molecules that alter immune function, and toxins” (Paddock, 2017) Numerous studies have been done and even more are advancing when it comes to the connection of childhood trauma and gut-related disease later in life. That is because of the brain-gut connection. “A recent meta-analysis has confirmed that childhood trauma contributes to a proinflammatory state in adulthood” (Leclercq, Forsythe, & Bienenstock, 2016).
Bacteria in the gut can be affected by emotional responses. “Stress hormones can alter their growth and damage the lining of the gut, allowing both bacteria and their toxins to get into the bloodstream. This can lead to inflammation, which is known to contribute to psychiatric diseases” (Paddock, 2017). Paddock explains that there are 3 strains of bacteria (Actinobacteria, Lentisphaerae, and Verrucomicrobia) that were different in people with PTSD; 2 of the 3 bacteria (Actinobacteria and Verrucomicrobia) are known to be important for regulating the immune system. She included a study done by Dr. Malan-Müller and her colleagues at the Stellenbosch University of 18 participants who were diagnosed with PTSD and 12 people without PTSD, but who did experience traumatic events (the control) and the findings were as follows: “that while the overall diversity of the gut microbe population in the PTSD and the trauma-exposed participants was largely similar, there were differences in the abundance of certain classes of bacteria…. It was concluded that “We therefore hypothesize that the low levels of those three bacteria may have resulted in immune dysregulation and heightened levels of inflammation in individuals with PTSD, which may have contributed to their disease symptoms (Malan-Muller)” (Paddock, 2017)
Another study included germ-free (GF) mice and has confirmed that the gut microbiome “as a major player in the development, structure, and function of both the enteric and central nervous systems and well as the maintenance and integrity of the blood-brain-barrier” (Leclercq, Forsythe, & Bienenstock, 2016). The study determines the important role of intestinal bacteria in “mediating changes in brain function and behavior such as depression, anxiety, and cognition. For instance, germ-free mice exhibit reduced anxiety-like behavior and impaired working memory compared with normally conventionally raised mice.” Furthermore, “in a landmark study, showed that the behavioral traits of more anxiety-like phenotype could be effectively adoptively transferred to mice that exhibited a less anxious phenotype by colonization with their donor gut bacteria. Behavior was therefore correlated with a specific gut microbial community” (Leclercq, Forsythe, & Bienenstock, 2016).
Several studies revealed in the book, Childhood Disrupted, How Your Biography Becomes Your Biology, and How You Can Heal, written by Donna Jackson Nakazawa, shows that there is a powerful connection between mental stress and physical inflammation. “When we experience stressful emotions—anger, fear, worry, anxiety, grief, loss—the HPA axis releases stress hormones, including cortisol and inflammatory cytokines, that promote inflammation.”
Nakazawa discusses several cases of adults who took the ACE survey and their scores ranged from 1 to 6. Each case had their own unique ACE story and each one suffered later in life from Celiac disease, heart disease, chronic fatigue, chronic headaches, fibromyalgia, degenerative disc disease, to multiple digestive diseases, skin diseases, depression, anxiety, and an overwhelming sense of fear long into adulthood. Their ages ranged from early thirties to their fifties. Felitti states “Time does not heal all wounds… Time conceals. And “…human beings convert traumatic emotional experiences in childhood to organic disease later in life.” According to best-selling author and speaker, Joan Borysenko, physical and emotional stress and negative feelings increase an inflammatory chemical interleukin 6 (IL-6) gene, depression and anxiety also increases the production of IL-6. Inflammation is common in heart disease, diabetes, osteoporosis, aging, cancers, and most chronic illnesses.
How can food affect stress and emotion? Borysenko explains that it changes the epigenome, changes the microbiome, which in turn helps regulate emotions, and has a direct effect on the nervous system. She further explains that gut bacteria and emotional balance play a role in synthesizing neurotransmitters including GABA, dopamine, and serotonin, affecting neurotransmitter metabolism and regulating blood levels, communicating with vagus nerve (gut-brain axis), and communicating with immune system, which in turn communicates with the brain and nervous system (immune-brain axis).
Nutrition & Lifestyle Support
Diet and lifestyle play a significant role in overall physical and mental health and well-being. Knowing what foods are harmful to the gut and the brain and which foods are nourishing both physically and mentally can be one of the most important ways to heal both the mind and the body. Having experienced childhood trauma, the likelihood of mental and physical diseases later in life are extremely high. Most chronic and autoimmune disease are caused by a lack of diversity in bacteria. When the gut is compromised, whether from leaky gut or dysbiosis, it affects how nutrients are absorbed into the body and the type of bacteria that live in the gut. The following diet and lifestyle recommendations can help with healing the gut and the diseases associated with adverse childhood experiences. Healing the gut will also help heal the mind.
Foods to avoid:
Processed foods – Increasingly, scientists think processed foods, with all their additives and sugar and lack of fiber, may be formulated in ways that disturb the gut microbiome, the trillions of diverse bacteria lining our intestines and colon. Those disturbances, in turn, may heighten the risk of chronic disease and encourage overeating. (Belluz, 2020) In addition, a lack of fiber leads to a lack of bacteria diversity as fiber feeds the good bacteria. If there is no fiber, the good bacteria starve to death and the bad bacteria takes over leading to a multitude of diseases and cancers.
Gluten – gluten can be inflammatory for some people and should be limited. Gluten can disturb the gut causing dysbiosis and triggering inflammation. Sources of gluten include wheat, rye, barley, breads, pizzas, pastas, baked goods, cereals and granolas, breading and coating, sauces and gravies, beer, and brewer’s yeast and even some cosmetics and supplements. (celiac.org)
Sugar – sugar not only affects the appetite hormones ghrelin and leptin, it also tasks the liver and can decrease the good bacteria in the microbiome and feed the bad bacteria, in addition to decreasing diversity in the microbiome. Sugar consumption is a risk factor for heart disease, cancer, diabetes, hypertension, premature aging, and obesity.
GMO foods – genetically modified organisms are a genetic modification of an actual transferal of DNA material from one species into another in order to achieve some desired characteristic. (BioKplus.com, 2018) When it comes to gut health, GMO foods can create a hostile environment within the microbiome, which can lead to a lack of good bacteria and an increase in the bad bacteria.
Foods to include:
Dark Leafy Greens – there are many benefits of including greens as a part of your daily diet. They contain an abundance of nutrients, phytonutrients, polyphenols, antioxidants, anti-inflammatory compounds, and a good source of fiber. Good for the brain and the gut. Greens help relieve stress as they provide folate, which help produce mood-regulating neurotransmitters such as dopamine and serotonin. They also contain magnesium for optimal vascular support. In addition, greens can delay the shortening of telomeres which is responsible for the progression of aging. (which is something that occurs during childhood trauma) The antioxidants and polyphenol compounds found in greens help support a health inflammatory response. “A recently discovered gene known as T-bet that gets switched on by cruciferous veggies such as broccoli or brussels sprouts instructs precursor cells in your intestinal lining to produce innate lymphoid cells (ILCs). ILCs protect your body against gut infections and inflammation, control food allergies and intolerances, support a healthy immune response, and seal the leaks in your gut. They also protect your body from bad bacteria, while the fiber in greens feeds your good bacteria, making leafy greens an all-around great choice for anyone dealing with gastrointestinal distress of any kind.” (Myers, 2020)
Beans and legumes – When properly prepared, beans are close to perfect in their nutrient profile. They are a great source of fiber, and include minerals like copper, zinc, and magnesium, and contain antioxidants and are a prebiotic. The fiber content in beans is called oligosaccharides, which “survive the acidic stomach and don’t get digested in the upper part of the gut. They make their way intact to the colon where they are fermented by beneficial bacteria. Gas is created during this fermentation process. It’s a good sign, one that says these healthful bacteria are being fed well, maintained, and enhanced through the right food choices, which in turn may lead to the prevention of diseases of the gut, as well as other organs in the body. Fibers from foods like beans that are able to reach the gut intact and stimulate growth and promote activity in the beneficial microflora.” (beaninstitute.com)
Variety of colorful vegetables – Including a wide variety of vegetables daily can improve gut health and prevent chronic illness and maintain existing diseases, even reversing them in some cases. Growing research shows that a diet rich in plant foods promote a diverse ecosystem of beneficial bacteria to support both human gut microbiome and overall health. In addition, “polyphenols, also abundant in plant foods, increase Bifidobacterium and Lactobacillus, which provide anti-pathogenic and anti-inflammatory effects and cardiovascular protection. High fiber intake also encourages the growth of species that ferment fiber into metabolites as short-chain fatty acids (SCFAs), including acetate, propionate, and butyrate. The positive health effects of SCFAs are myriad, including improved immunity against pathogens, blood–brain barrier integrity, provision of energy substrates, and regulation of critical functions of the intestine.” (Tomova et al., 2019)
Fermented foods – Fermented foods are a great way to incorporate a good dose of probiotics into the diet. According to Dr. Axe, “It’s the process of using microorganisms, such as bacteria or yeast, to convert carbohydrates to alcohol or organic acids under anaerobic conditions.” He further states, “…fermentation helps increase digestion and bioavailability of nutrients, as well manage and prevent disease, including H. pylori infection, cancer, liver disease, arthritis, inflammatory bowel disease and lactose intolerance. Furthermore, it’s been shown that fermented foods can reduce social anxiety.” Good sources of fermented foods are live and active yogurt, kefir, sauerkraut, kimchi, miso, and tempeh.
Omega-3 Fatty Acids – Essential fatty acids (EFA) are important for maintaining balance in gut bacteria. It works to reduce the bad bacteria and increase the good bacteria. Omega-3 fatty acids increase the gut bacteria that produce anti-inflammatory chemicals called short-chain fatty acids (SCFA). Butyrate, a SCFA has been linked to protecting against diseases like bowel cancer, diabetes, and depression. (Sandall). In addition, omega-3 can also reduce fat in the liver, which is very helpful to those who have fatty liver disease (non-alcoholic fatty liver). It works by reducing the amount of fat in the liver and reducing inflammation that is associated with it. (Hjalmarsdottir, 2018) The best sources of omega-3s can be found in fish such as mackerel, salmon, herring, sardines, and plant sources include nuts and seeds like chia and pumpkin, walnuts, green leafy vegetables, and tofu.
Bone broth – Dr. Axe suggests bone broth for his patients because it contains collagen and amino acids proline and glycine both of which help to heal damaged cell walls. He recommends a 3-day bone broth fast for leaky gut and autoimmune disease. Bone broth is easily digested, which is important for a damaged gut and can help reduce inflammation.
Coconut – “Coconut products of all kinds, including oil, cream, and yogurt, are antimicrobial, antifungal, and antiviral, which makes them extremely helpful when dealing with SIBO, Candida overgrowth, and parasites. Medium-chain triglycerides (MCTs) in coconut aid in nutrient absorption. They’ve also been shown to be particularly beneficial for managing gastrointestinal disorders. Coconut yogurt comes with the added bonus of probiotics to encourage the growth of good bacteria in your gut.” (Myers, 2019) I recommend CocoYo living coconut yogurt by GTS Living Foods (gtslivingfoods.com), which contains 25 billion CFUs at the time of bottling and contains no sweeteners, added flavors, or colors. It is pure coconut with beneficial probiotics. Adding some fresh berries, raw cacao nibs, walnuts, and seeds are a great addition as they are all great for the gut as well.
Apple cider vinegar – Amy Myers, MD suggests ACV to help heal the gut. It can inhibit the growth of harmful bacteria that can cause leaky gut. In addition, it helps produce hydrochloric acid (HCL) which helps those who have gastroesophageal reflux disease (GERD) or acid reflux. This aids in digestion and nutrient absorption, which further enhances immune function.
Synbiotics – A combination of probiotics and prebiotics. Both works together to diversify the gut microbiome. Both can be taken as a supplement or food sources.
Probiotics – live bacteria that line the digestive tract and help with nutrient absorption and fight infections. There are many benefits of probiotics from digestive health to disease prevention; they are the core of our overall health and well-being. Due to modern sanitation practices, probiotics have become scarce in our foods, so being conscience of choosing probiotic-rich foods is essential to healing the gut. There are different strains of probiotics and each strain has a different function, so choosing the correct blend of probiotics is helpful. The two main strains are Bifidobacterium and Lactobacillus. Within these strains are different types and some are found naturally in the body (gut), but can also be found in various foods and supplements. Below is a guide from healthline.com that displays the type of bacteria, the source and its benefit(s).
Prebiotics – “They nourish and stimulate the growth of good bacteria while promoting a reduction in disease-causing bacteria… [like] probiotics, they acidify the intestinal environment, enhancing the absorption of essential minerals.” Other benefits include: promoting the growth of lactobacilli and bifidobacterial; lower colon pH, prevent constipation and diarrhea; helps keep blood sugar levels even, and useful for those with liver disease. There are many food sources of prebiotics that include the following: honey, asparagus, bananas, dandelion greens, endive, fruit, garlic, green tea, Jerusalem artichoke, legumes, kefir, peas, and soybeans. (Lipski, 2012)
L-Glutamine – there are several benefits of this amino acid, but it is well-known for its gut-healing ability. It helps restore your gut lining by regenerating calls faster by protein synthesis. It also helps to regulate blood sugar levels and reduces inflammation. In addition, l-glutamine” …can help you address digestive issues, manage your immune response, and support intestinal health. It can assist with the management of symptoms of IBS and diarrhea by helping balance the mucosal production in your gut, which leads to healthy bowel movements.” (Myers, 2019) It can also enhance mental function. Sources of l-glutamine include raw spinach or parsley, eggs, seafood, nuts, beans, and legumes. A daily supplement is recommended if treating existing autoimmune disease or chronic digestive problems.
Slippery Elm – loaded with prebiotic starch, slippery elm creates a healthy mucous layer in the GI tract, which helps sooth inflamed bowels, stomach, and urinary tract and also serves as food for good bacteria. (Mase, 2018) It is a great source of iron, magnesium, zinc, potassium, and vitamins B1, B2, B3, and vitamin C. In addition, it is good for diarrhea and ulcers and is beneficial for those with IBD and diverticulitis. (Balch, 2010)
Marshmallow root – “has a high mucilage content, which covers your digestive tract with a protective lining and eases inflammation in your gut, helping to soothe ulcers, diarrhea, and constipation, as well as restoring the integrity of the small junctions found in your digestive system.” (Myers, 2019) Nutrients include: amino acids, calcium, iron, magnesium, manganese, selenium, and vitamins B1, B2, B3, and C. Marshmallow is good for digestive upsets, fluid retention, intestinal disorders, kidney problems, aids the body in expelling excess mucous. (Balch, 2010)
Burdock – provides a rich source of inulin and prebiotic starch. It includes nutrients like amino acids, chromium, copper, iron, magnesium, phosphorus, and vitamins B1, B2, B3, and C. It helps to build a healthy microbiome (Mase, 2018) and is a good detoxifier. Acts as an antioxidant and has antibacterial and antifungal properties. It also restores liver and gallbladder function; it also stimulates the digestive and immune systems. (Balch 2010)
Exercise – daily movement has been shown to increase diversity within the microbiome. Regular exercise (150 minutes of moderate to vigorous exercise per week) can enhance the production of short-chain fatty acids, which help to produce beneficial microbes. In addition, exercise increases the production of dopamine and serotonin. It is a great stress-reliever, which has an overall impact on gut health; promotes healthy digestion by reducing inflammation, constipation, and bloating and enhances immune function.
Meditation – stress is a factor in gut health and meditation is a very helpful technique to reducing and eliminating stress. According to Integrative Nutrition, the benefits of a regular meditation practice include the following:
Takes you out of the “fight or flight” mode - When stressed, the body responds by going into “fight or flight” mode. After a prolonged period, this response can wreak havoc on our health. Meditation turns on the opposite response by promoting balance and calmness, which helps you live a more fulfilled (and less upset!) life.
Lowers your stress hormones - Cortisol, a major stress hormone, is released when you’re stressed. The more stressed you are, the more cortisol the body has to produce to try to cope. High levels of cortisol can contribute to anxiety, brain fog, depression, insomnia, and mood swings. Excess cortisol can also affect your body’s insulin response and lead to inflammation. By meditating, you’ll help reduce cortisol levels by inducing a state of calm, enhancing your cognitive functions and improving your mental health.
Clears your mind, enabling you to relax - Meditation challenges you to leave your worries behind so you can commit to a state of total relaxation. This might lead to better sleep, greater focus, and increased creativity – all things bound to make you feel more positive and less stressed throughout the day!
Stabilizes breathing and heart rate - Similar to yoga, meditation focuses on deep breathing and becoming aware of each breath you take. This is the opposite of stress, which increases heart rate and causes breathing to become more erratic.
Enables long-term resilience - Regular practice improves your response to stress over time. You might feel stronger mentally and emotionally, and things that once added stress to your life might not bother you as much.
Get a dog – Petting or playing with a dog releases oxytocin, dopamine, and endorphins. Oxytocin decreases stress, lowers blood pressure, and lowers heart rate. (Borysenko, 2017) Also, according to the American Kennel Club (AKC), dog-owners experience less stress when interacting with their dog, as playing with them “…lowers blood pressure and heart rate, slows breathing, and relaxes muscle tension almost immediately.” AKC also states that dog-owners tend to be more active. “Dog owners are more likely to engage in moderate physical activity than non-dog owners. In fact, dog owners walk an average of 300 minutes per week, while non-dog owners walk an average of 168 minutes a week.” (AKC, 2017)
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