No Girl, It’s Not “All In Your Head.”
Irritable Bowel Syndrome, or IBS, is a collection of gastrointestinal symptoms with an origin that cannot be identified. Symptoms include abdominal pain, excessive gas and bloating, severe stomach pain, chronic constipation or diarrhea, nausea, fatigue, and more. These symptoms are chronic, occurring for at least one year, and can wreak havoc on peoples’ lives. So many of the sufferers of IBS are told by practitioners that “it’s all in their head,” and this type of medical gaslighting can create additional trauma for the individual, which in turn can make IBS worse.
If you’ve been told that, I am here to tell you: it’s not all in your head. There are very real physiological factors that play into IBS. Here are some of the truths that we don’t frequently hear in the modern medical world.
Truth #1: There are Real, Physiological Symptoms from a Non-Stress Root Cause
The root causes for IBS can include a wide variety of physical underlying concerns, including:
Small intestinal bacterial overgrowth (SIBO)
Food intolerances
Leaky Gut
Parasites living in the gut
Yeast overgrowth
Zinc or magnesium deficiency
Heavy metal toxicity
Most notably, up to 80% of IBS sufferers have small intestinal bacterial overgrowth, known as SIBO. This condition increases bacteria that ferments food in the small bowel, which increases gas and causes a host of other uncomfortable symptoms. The latest research suggests that while IBS was originally thought to be due to psychological factors, it is now clear that it is of a more organic nature.
Since the human gut includes approximately 10x more bacterial cells than human cells, it makes sense that our GI tract can be vastly influenced by microbial populations (including bacteria, fungi, and viruses). There are over 50 bacterial phyla that have been associated with the human gut, including Bacteroidetes and Firmicutes, and our normal gut flora usually provides several benefits to us.
In fact, our bacteria in a normal state can help us ferment undigested dietary residues (think: fiber) and help us perform a lot of important functions: they help us maintain a healthy immune system, keep our pH balanced, metabolize drugs and hormones, synthesize important nutrients and vitamins, and provide nutrients to the colonic epithelial cells. But with SIBO, bacteria migrates and populates in the small intestine, leading to gas, bloating, and other unpleasant symptoms due to the fermentation of digested food in the wrong portion of the GI tract.
Truth #2: There Can Be an Autoimmune Component
When increased intestinal permeability, otherwise known as “leaky gut,” occurs, the tight junctions that line the intestines become loose or compromised, and allow particles (food, toxins, protein, etc) to incorrectly pass through the gut lining. To visualize this, imagine a cheese cloth. When the cheese cloth is working, it drains curds to make cheese; if there is a hole in it, suddenly the entire curd passes through the cheese cloth. The same is true of our tight junctions with food particles, toxins, and proteins.
A leaky gut condition can lead to the development of numerous autoimmune conditions, including rheumatoid arthritis, ulcerative colitis, and Crohn’s. Once a pathogen makes its way past the gut lining, our adaptive immune system targets the pathogen with T-Cells and B-Cells. The T-Cells are comprised of white blood cells that recognize and attach to a pathogen, then secrete cytokines, which tell B-Cells to produce antibodies. Once this happens, it can cause an overreaction from your body if this specific food that passed through the gut lining is eaten again because now your body thinks of it as an invader. From the leaky gut condition, we can develop food intolerances, which are physical reactions that occurs when our bodies can no longer tolerate a specific food (or food group), which causes further digestive disturbances.
Additionally, food poisoning is the lead cause of IBS-D. In fact, one in nine people who get food poisoning will go on to develop IBS. This is triggered by an autoimmune response that can lead to nerve damage in the gut, which can then contribute to more bacterial overgrowth, and more uncomfortable symptoms for the sufferer.
If you suspect this could be the case, it is important to have a functional doctor run several tests that may help you get a clearer picture of the root cause. These tests include lactulose/mannitol tests, (which can check for leaky gut), microbiome testing (to assess the diversity and composition of microbes in the gut), fecal elastase (to check pancreatic enzymes), fecal calprotectin (to look for inflammation in the stool) secretory IgA/ sIgA (to assess digestive immune function), and C-reactive protein, or CRP (to check for inflammation in the body).
Truth #3: A Low FODMAP Diet Is Not the Only Treatment Option
A low FODMAP ( Fermentable, Oligosaccharides, Disaccharides, Monosaccharides, Polyols) diet is commonly recommended for those with IBS. It is a way of eating designed to help individuals with chronic gut conditions by limiting common food triggers and to help manage symptoms. Foods with short-chain carbohydrates (sugars) include lactose, foods rich in fructose (like pears and apples), and foods that contain high levels of polyols (like watermelon). These foods are considered high-FODMAP because they contain high amounts of these sugars. Low-FODMAP foods contain little to no short-chain carbohydrates.
This dieting strategy can help those struggling with IBS because there are less fibers to ferment, and therefore less gas is created, and so there are less symptoms. However, if there is bacterial overgrowth driving the IBS or there is an autoimmune process involved, then a low FODMAP diet will not cure the underlying cause. Further, restricting our fiber intake will also restrict the food source for good bacteria in the gut microbiome, which can actually lead to an imbalance of good flora and therefore lead to additional problems down the road. This diet can also exacerbate symptoms by increasing food stress and fear, which creates additional stress to the body.
So no, IBS is not simply “all in your head.” It’s not your stress. It’s not your depression. And it is not your anxiety.
We now know that IBS has various physiological root causes, including SIBO, and autoimmune processes, such as leaky gut and food intolerances, that can drive the symptoms of IBS. While stress, depression, and anxiety can exacerbate this condition, they are not the drivers behind your IBS.
In addition to understanding what could be at the root cause of your IBS for your healing journey, it is important to be patient with yourself and understand that your treatment modality will be bio-individual for you. It is important to work with your healthcare provider to seek the right diet plan and supplements to help you heal. While you are testing with providers as needed, it is also important to avoid common triggering foods (such as gluten, conventional dairy, processed foods, artificial sweeteners, corn, and alcohol) while also engaging in stress reduction techniques, the right therapeutic tools, and rest. Just know, you are not alone and wellness can be achieved.
Works Cited
Holt, Erin. “Understand IBS.” Invisible Illnesses. The Institute for Integrative Nutrition. 2022. New York, New York. Lecture.
Malinen E, Krogius-Kurikka L, Lyra A, et al. Association of symptoms with gastrointestinal microbiota in irritable bowel syndrome. World J Gastroenterol. 2010
O’Hara AM, Shanahan F. The gut flora as a forgotten organ. EMBO Rep. 2006;7:688–693. doi: 10.1038/sj.embor.7400731.
Sekirov I, Russell SL, Antunes LC, Finlay BB. Gut microbiota in health and disease. Physiol Rev. 2010;90:859–904. doi: 10.1152/physrev.00045.2009.