The Low-FODMAP Diet Step by Step

Chapter 1

GUT ISSUES? THE ROLE OF FODMAPS IN DIGESTIVE DISTRESS

DISTRESSED BY DIGESTIVE SYMPTOMS? You are not alone. One in four people in the United States suffers regularly with a faulty gastrointestinal (GI) tract leading to uncomfortable symptoms. Irritable bowel syndrome (IBS), an unrelenting and often debilitating GI motility disorder, strikes one in seven Americans, resulting in gas, bloating, cramping, pain, and alteration in bowel habits.¹ Celiac disease, inflammatory bowel disease, heartburn, and gastro-esophageal reflux (GERD) are just a few of the digestive diseases on the rise, globally. Increasingly, many are stopped in their tracks due to digestive discord. Because GI symptoms can’t be seen, just felt, and topics about digestive distress are often taboo, many simply suffer in silence. Here’s the good news: We have an effective, holistic nutrition solution for you and your troubled gut!

By simply modifying certain sugars and fibers in your diet, collectively known as FODMAP carbohydrates, you may find your tummy troubles are completely gone, literally in one day! Don’t be put off by the big, somewhat intimidating acronym FODMAP. We will break everything down for you in real English. As a brief introduction, FODMAP carbohydrates include lactose, fructose (in excess of glucose in a food), fructans, galacto-oligosaccharides, and polyols, types of sugars and fibers found in everyday foods, such as apple, pear, watermelon, wheat, onion, and garlic, to name a few. When FODMAP carbohydrates are malabsorbed in the intestine, they drag water into the gut, stretching it. Furthermore, the residential gut microbes feast off the poorly digested FODMAPs, creating gas. If you have a sensitive tummy, these malabsorbed carbohydrates can cause a cascade of GI symptoms. Although you may think a diet to calm your digestive woes will be bland, tasteless, and full of deprivation, we have the most delicious solution right here for you, using fresh whole foods that you can easily find in any supermarket. This book will help you customize your own low FODMAP plan; you’ll quell your upset belly with easy-to-prepare recipes that will soon be your new family favorites, for the low FODMAP diet followers and their family members alike. Before we get to the plan and recipes, let’s talk a bit more about digestive problems and how changing your diet just might turn your life around in only a few days.

Gut Problems? Common GI Disorders

As mentioned, irritable bowel syndrome (IBS) is a digestive health condition that presents with abdominal bloating, gas, pain, alteration in bowel habits, urgency, or a feeling of incomplete emptying. It is the most common intestinal disorder diagnosed by gastroenterologists and occurrs in 7 to 20 percent of the US population, impacting the quality of life of 25 to 45 million Americans!² In addition to experiencing digestive distress, individuals with IBS often suffer anxiety and depression. IBS can develop at any age and is more common in women than men.³

The symptoms of IBS appear due to a malfunction in the way your intestine, brain, and nervous system talk and/or work with one another. People with IBS may have other coexisting digestive disorders, such as inflammatory bowel disease (IBD), GERD, celiac disease, lactose intolerance, or nonceliac gluten or wheat sensitivity; IBS can also appear on its own.

For years, patients with IBS have connected food as a symptom trigger. Yet only very recently has the medical community offered an effective nutritional approach that works to keep symptoms at bay. Researchers at Melbourne, Australia’s Monash University proved through numerous studies that a specific group of commonly malabsorbed carbohydrates are the culprit for symptom exacerbation in many with IBS. In fact, studies worldwide have shown that about 3 in 4 IBS patients will experience symptom relief from following a diet modified in foods rich in FODMAP carbohydrates.⁴

Gastro-esophageal reflux (GERD) occurs commonly with a sensation of burning in the throat, often referred to as heartburn, a sour or bitter taste in the mouth, difficulty with swallowing, or a dry cough. The changing diet landscape, obesity epidemic, and stress are likely all contributing factors to the rise in this condition. It is estimated that GERD occurs in 18 to 28 percent of North Americans.⁵ The low FODMAP diet might help mitigate GERD symptoms, as some indigestible carbohydrates can lower the pressure of the lower esophageal sphincter, the door between the stomach and esophagus. The lower pressure allows the sphincter to open more readily, releasing the acidic stomach contents into the esophagus, causing GERD symptoms. Fructans, a fiber and source of FODMAPs, have been linked with reflux.⁶ More on these frustrating fructans later in this chapter.

Inflammatory bowel disease (IBD) is not the same as IBS. It primarily includes Crohn’s disease and ulcerative colitis, which are chronic autoimmune disorders that present with inflammation in the intestine. They differ slightly: Crohn’s disease can occur anywhere in the digestive tract, but most often in the lowest section of the small intestine, whereas ulcerative colitis is limited to the large intestine only. The low FODMAP diet has been shown to help manage ongoing IBS-like symptoms in those with IBD.⁷

Celiac disease is an autoimmune condition in which gluten is toxic to the small intestine. Celiac disease is on the rise, occurring in at least 3 million, or in about 1 in 133 Americans. Untreated, celiac disease can present with IBS-like symptoms; left untreated, it can also put a person at risk for intestinal cancer, infertility, osteoporosis, anemia, and other autoimmune conditions. Unfortunately, most people with celiac disease don’t know they have it. According to the University of Chicago’s renowned celiac center, only about 17 percent of individuals with celiac disease have been diagnosed. On average, it takes eleven years for a person with symptoms to be diagnosed. Despite strict vigilance to a gluten-free diet, 20 to 23 percent of treated celiac patients fulfill the diagnostic criteria for IBS.⁹ For these individuals, a low FODMAP gluten-free diet may offer improved symptom management.

Small intestinal bacterial overgrowth (SIBO) occurs when abnormal amounts of gut microbes seed the small intestine and overgrow in great numbers. Normally, the small intestine has limited bacteria. When bacteria populate the narrow tube of the small intestine, they will consume and ferment any small carbohydrates that escape digestion. The resultant fermentation can lead to pain, cramping, distention, and bloating; some sufferers may experience constipation; others may have diarrhea. Symptoms of SIBO mimic those seen in IBS. Although not adequately studied in the research setting, many SIBO sufferers find symptom relief on a low FODMAP diet, as FODMAPs are fast food for small intestinal microbes.

Digestion 101

Understanding the science of digestion can be helpful when sorting out your personal digestive challenges. Digestion is individual. What works for you might not work for your best friend. This is due to important factors, such as the genes we inherited from our parents and what microbes reside in our gut. The colon is one of the most diverse ecosystems on Earth! And we all have our very own “fingerprint” of microbes that reside there. Microbes play a big part in the digestive process. They produce digestive enzymes we don’t have. In fact, the human body has twenty genes relating to carbohydrate digestion and some microbes have over two hundred! Some microbes, called vigorous fermenters, are capable of creating copious amounts of gas from our undigested food. When microbes ferment carbs, they produce carbon dioxide, hydrogen, and/or methane gas, which can impact intestinal movement. Too much methane gas in the intestine is associated with constipation, whereas elevation in hydrogen gas is associated with diarrhea. Our gut microbes not only help us digest foods but they regulate our immune system and synthesize vitamins for us, too.

The digestive tract comprises the mouth, esophagus, stomach, and small and large intestine. Digestion starts in your mouth. Your pearly whites are meant to break up food, increasing its surface area, which allows the digestive enzymes in your saliva to start the process of digestion. Most of what we eat should be broken down partially in the stomach and in the small intestine, where nutrients are actively transported into the bloodstream to nourish and energize our body. Wolfing down food and rushing while eating incorporates more air into your digestive tract, setting yourself up for faulty digestion and intestinal distress. Try your best to set aside time to eat in a relaxed setting.

Residual undigested food matter, mostly fiber, but also some poorly absorbed protein, carbs, and fats will move from your small intestine into the colon. The primary role of the colon is to absorb water, provide residence to important gut microbes that further break down foods, create important vitamins, and eliminate the end products of digestion. When too much undigested food substrates arrive in the colon, the residential microbes feast and create the all too well-known and felt plentiful amounts of gas.

The human intestine is made up of a complex of nerves and muscles that help move food along the GI tract. Two major modes of operation occur in the intestine: the eating mode and the cleaning mode. When you eat, your intestine is secreting digestive enzymes and sloshing the food around to break down the nutrients into their digestible form. When you are not eating, your intestine will initiate a repetitive and important housecleaning wave, called the migrating motor complex, to clean up the small bowel and to get it prepared for the next meal. It is important to leave three to four hours between eating, to allow this cleansing wave to take place; otherwise, your small intestine can become a petri dish as microbes, food, and debris can accumulate. For this reason, we recommend eating three meals and one snack per day rather than several small meals or a grazing-style eating pattern. Yes, you and your sensitive gut need a little downtime between meals!

What You Need to Know Prior to Changing Your Diet

First off, do not self-diagnose yourself with any GI disorder. Visit with your primary care doctor and/or a gastroenterologist to rule out serious conditions for your GI distress, such as untreated celiac disease, inflammatory bowel disease, small intestinal bacterial overgrowth, GERD, parasitic infections, or even in the rare instance, cancer. Understand that in some instances, diet may be only part of your treatment plan along with other traditional medical therapies.

A special note about celiac disease: It is advised that you be screened for celiac disease before embarking on the low FODMAP diet. Treatment for celiac disease is a lifelong gluten-free diet. Although the low FODMAP diet is not a gluten-free diet, it does reduce gluten intake. Testing for celiac disease requires adequate gluten intake, so the test may not be accurate if it occurs while following the low FODMAP diet.

Gluten and IBS Symptoms

Some people who do not have celiac disease do note symptom improvement on a gluten-free diet. Gluten sensitivity, otherwise known as nonceliac gluten sensitivity (NCGS), presents with a cascade of symptoms associated with eating gluten, including brain fog, depression, hyperactivity, joint pain, and IBS-like symptoms. although these symptoms may occur in people with celiac disease, those with NCGS do not have the genes or antibodies present for celiac disease to occur. The symptoms, however, dissipate when gluten is removed from the diet and reoccur when gluten intake is resumed.

Research has shown that in people with NCGS who have digestive symptoms, the elimination of gluten (which simultaneously restricts FODMAP-containing grains: wheat, barley, and rye) from the diet might lessen gastrointestinal symptoms, but this effect is likely due to the reduction in FODMAPs rather than the elimination of gluten.¹⁰ If you are unsure whether you are gluten sensitive, we recommend you work with a registered dietitian to guide you. If you have irritable bowel syndrome, the research suggests that FODMAPs (not gluten) in your diet are the most likely contributor to your digestive complaints.

Let’s Talk FODMAPs

As previously mentioned, FODMAPs are a group of small carbohydrates found in many everyday foods. This collection of small sugars and fibers are commonly malabsorbed in the intestine and can contribute to GI distress in someone with a sensitive gut. “FODMAP” is an acronym for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. Whew! That’s a mouthful.

Unfortunately, you don’t often see the terms oligosaccharide or disaccharide on a food label. Deciphering what foods have these FODMAPs can be tricky. No need to worry; we’ve got you covered! The following chart offers a closer look at the FODMAP acronym and FODMAP subtypes (lactose, excess fructose, fructans, galacto-oligosaccharides, sorbitol, and mannitol).

Why Are FODMAPs Malabsorbed?

Lactose, the sugar in cow’s, sheep’s, and goat’s milk, is commonly maldigested. For lactose to be adequately absorbed in the intestine, the enzyme lactase needs to be present. Unfortunately, lactase enzyme production reduces as we age, and genetically some ethnicities, such as Asians and African Americans, make less lactase. Small amounts of lactose (0 to 2 grams) as found in hard cheese and butter should not trigger typical lactose malabsorption symptoms, such as gas and bloating, and can be enjoyed while on the low FODMAP diet. Foods with larger amounts of lactose, such as the 12 grams found in 1 cup (240 ml) of milk, however, may trigger IBS symptoms and are not allowed on the low FODMAP diet.

Fructose, a one-chain sugar that is slowly absorbed throughout the small intestine, is best absorbed when glucose is present at the same time. When the fructose content of a food exceeds the glucose content, we call that a source of “excess fructose.” Transporters in our intestine help move fructose from our intestine into our blood for absorption and some rely on glucose to guide the process. Some people lack some of the fructose transporters, making fructose malabsorption (FM) more likely. Previous surgical resection of the small intestine or a fast-moving small intestine can also contribute to the malabsorption of fructose. FM is quite common, occurring in 1 in 3 people; however, not everyone experiences symptoms from malabsorbing fructose. For those who develop symptoms with excess fructose ingestion, the low FODMAP approach certainly can help! Foods with equal amounts of fructose and glucose, or those that contain more glucose than fructose, are absorbed more efficiently and considered suitable choices for the low FODMAP diet. It appears that the intestine has a limited capacity to handle too much fructose (even when glucose is present) all at once; therefore, we recommend you limit yourself to one serving of fruit per meal or snack time. The goal is to absorb fructose adequately to ward off any potential GI distress caused by its malabsorption. We will remind you throughout the book how we would like you to modify your fruit servings. Fruit is delicious and nourishing, but like most things in the low FODMAP realm, it is all about moderation and balance.

FODMAP: The Acronym

Lastly, let’s talk about fructans, galacto-oligosaccharide (GOS), and polyols. Oligosaccharides (fructans and GOS) are malabsorbed by all humans, as we lack the enzymes to break them apart. GOS are found in all beans, such as kidney beans and black beans. Although we know a big bowl of chili will give rise to intestinal gas in just about everyone, if you have IBS, the gas can lead to debilitating pain. Polyols, also known as sugar alcohols, are poorly absorbed, too, especially when consumed in large quantities. Sorbitol and mannitol are the most prevalent polyols found naturally in foods, but they may also be used as sweeteners in sugar-free gum and mints, along with other manufactured polyols, such as xylitol, maltitol, and isomalt. Note the -ol ending when reading labels. Sorbitol and mannitol are absorbed slowly and insufficiently via pores in the small intestine. Some polyols may be absorbed, but all too often, they are too big or move too quickly through the intestine and can contribute to diarrhea, especially when consumed in larger quantities. Inflammation in the intestine may reduce pore size, making polyol malabsorption even more likely. For example, in an individual with newly diagnosed celiac disease or inflammatory bowel disease where inflammation plays a big role, polyol absorption likely will be impaired.

Malabsorbing FODMAPs does not cause IBS or contribute to symptoms for everyone. For individuals with a highly sensitive intestine, however, the malabsorbed FODMAPs can lead to major digestive distress.

How Do FODMAPs Contribute to IBS Symptoms?

Short-chain, in other words, small FODMAP, carbohydrates pull water into the small intestine, stretching the intestinal wall, which can contribute to pain, cramping, and bloating. The extra water travels to the colon, where it can lead to diarrhea in people with a fast-moving intestine. Those with a sluggish intestine might feel cramps and pain from the water stretching the intestine, like a water balloon inside their gut! Moreover, these poorly digested FODMAPs arrive in the colon intact and become a hearty food supply for the millions of microbes that reside there. When the microbes feed off the FODMAPs, the act of fermentation creates copious amounts of gas.

An additional side effect of fermentation is the production of short-chain fatty acids (SCFA). SCFAs can typically be a healthy side effect of fermentation in the intestine, as they can act as nourishing fuel for the cells of the colon. SCFAs, however, can speed the motility of the large intestine, too, and can cause injury to the colon wall if there is an overproduction of these acids. It’s all about balance.

The distention caused by the gas and water driven by malabsorbed FODMAPs is one way these poorly absorbed carbohydrates can contribute to GI distress, but additional factors may play a role also. When residential microbes feast on undigested sugars and fibers, they may produce toxic or inflammatory metabolites. The stretching of the intestine may cause the release of even more inflammatory chemicals via mast cells that line the intestine. Mast cells are filled with inflamatory compounds. As previously mentioned, people with IBS often experience anxiety and depressive symptoms. Interestingly, the low FODMAP diet has been shown in emerging research to minimize these symptoms; it appears the low FODMAP diet impacts the immune system of the gut and the brain, too, contributing to a reduction in these mental health conditions.¹¹ Nutritional science can be complex and the full beneficial effect of a low FODMAP diet for individuals with IBS is still being determined through further research.