Individualized elimination diets guided by leukocyte activation tests reduced symptoms of irritable bowel syndrome (IBS) better than a sham diet in a randomized controlled trial.
Researchers concluded that this dietary strategy may enable patients with IBS to alleviate their symptoms with fewer food restrictions than those required by the low FODMAP diet, which could improve long-term adherence. “We didn’t expect results like this,” Ather Ali,ND, MPH, MHS, assistant professor of pediatrics and of medicine at Yale School of Medicine, said in a press release. “The people who consumed the diet consistent with the test did significantly better than people on the sham diet.” In a parallel-group, double-blind trial, Ali and colleagues analyzed blood samples from 58 adults with IBS (mostly white women) using a leukocyte activation test to measure immune response to individual foods. Then they randomly assigned participants to adhere to a diet restricting meals consistent with the test results, or to a sham diet restricting foods inconsistent with the test results, for 4 weeks.
An average of 13 foods was eliminated among all participants out of a possible 200 that were tested, the most common of which included strawberries and cinnamon (low FODMAP foods) followed by almonds, apples, onions and pears (high FODMAP foods). Additionally, overall diet adherence rates were statistically comparable, and patients reported no adverse effects related to the intervention. Patients on the individualized diet showed significantly more significant increases in IBS Global Improvement Scale (GIS) scores compared with those on the sham diet, which served as the primary endpoint. At 4 weeks, the mean difference in scores between groups was 0.86 (95% CI, 0.05-1.67), and at 8 weeks it was 1.22 (95% CI, 0.22-2.22).
Both groups showed significant improvements in IBS Symptom Severity Scale scores, but those on the individualized diet showed significantly higher reductions relative to the sham diet. At 4 weeks, the mean difference in score change from baseline between groups was –61.78 (95% CI, –4.43 to –119.14), and at 8 weeks it was –66.42 (95% CI, –5.75 to –127.09). Both groups experienced statistically comparable changes in mean IBS Adequate Relief and quality of life scores. Further analysis of plasma samples from strong responders showed that reduced levels of a single protein (neutrophil elastase) were associated with reduced symptoms.
The investigators concluded that this study provides novel data supporting the strategy of using leukocyte activation testing to develop individualized diets for IBS. “If these intriguing results can be replicated in larger and more diverse samples they can provide insight into another way to treat a condition that can often be very frustrating,” Ali said in the press release. “It can be debilitating, and patients are often looking for dietary approaches to it.” – by Adam Leitenberger
Adapted from: Ali A, Weiss TR, McKee D, et al. Efficacy of individualized diets in patients with irritable bowel syndrome: a randomized controlled trial. BMJ Open Gastroenterology2017;4:e000164. doi: 10.1136/bmjgast-2017-000164
Daily Nutrition Nugget
Eating healthy on a budget can seem difficult…But it can be done! Many fruits, vegetables, and legumes (beans and peas) cost less than $1 per serving.
Even the most health-conscious among us can go a little crazy on snacks and drinks during the holidays and at springtime and during the summer months, and before we know it, we are back at the holidays. Really, where does the time go? If we are having fun with people we love and care about, then that may also be another reason for indulging in our favorite snacks and drinks. So, when is it not a perfect reason or season to fall victim of the snack trap?
Thankfully, you can kind of have your cake and eat it, too. It’s OK to indulge a little in the foods you love, as long as you know how to get your body back on track. One of the best ways to help your body feel like it’s working at an optimal level is to support the bodies natural detoxification. Your organs are already incredibly well-suited for detoxing things, such as heavy metals, pathogens, and other deleterious compounds from its system. However, sometimes, especially when it’s overloaded and working overtime, your body can use a little bit of detox support.
Eating these foods regularly will help you feel energized and clear-minded. You’ll also notice that side effects of chronic inflammation caused by toxins will disappear. For many people, common side effects are bloating, indigestion, and weight gain, so in a sense, these are “flat tummy” foods, too!
Beets: The root veggie is available year round, but be sure to grab a few at the farmers market before your next summer cookout. Beets support healthy liver function and help it filter out toxins all thanks to something called betaine. This compound, unique to raw beetroot, encourages the liver to cleanse itself and promotes healthy bile production. Try wrapping beets in foil and throwing them on the grill next time you BBQ!
Grapefruit: Juicy, sweet, and tart, grapefruits are good to keep on hand the morning after a heavy meal. The antioxidants in the citrus fruit protect cells from free radical damage. Grapefruit is also very high in fiber, which acts like a broom for your digestive system, sweeping out the gut and intestines until everything is clean and good as new.
Dandelion Root Iced Tea: Not exactly something you can snack on, but still an excellent detoxifying ingredient to have in your pantry! Dandelion Root promotes the production of bile in the liver. In other words, it helps your liver break down and cleanse your internal organs. Make a big batch and sip on this stuff the morning after a night out.
Asparagus: According to the Journal of Food Science, the amino acids and minerals found in asparagus protect liver cells. Because so much of detoxification happens in the liver, it’s important to support this critical organ however possible.
Avocado: Next time you’re feeling a little woozy after one too many skinny margaritas, whip up some avocado toast. A study published in The Journal of Agricultural Food Chemistry found that of all fruits, avocado has the most liver-friendly benefits. It’s even able to reverse liver cell damage!
Daily Nutrition Nugget
Be an advocate for healthier kids! Insist on good food choices at school and childcare centers. Contact public officials and make your voice heard.
For the broccoli haters of the world, researchers may have more bad news: the vegetable may also help promote a healthy gut.
In a study, when mice ate broccoli with their regular diet, they were better able to tolerate digestive issues similar to symptoms of leaky gut and colitis than mice that were not placed on a broccoli-supplemented diet, according to Gary Perdew, the John T. and Paige S. Smith Professor in Agricultural Sciences, Penn State. He added that other vegetables, such as Brussels sprouts and cauliflower, may also have similar gut health properties. “There are a lot of reasons we want to explore helping with gastrointestinal health and one reason is if you have problems, like a leaky gut, and start to suffer inflammation, that may then lead to other conditions, like arthritis and heart disease,” said Perdew. “Keeping your gut healthy and making sure you have good barrier functions so you’re not getting this leaky effect would be really big.”
Good intestinal barrier function means that the gastrointestinal (GI) tract is helping protect the intestines from toxins and harmful microorganisms while allowing nutrients to pass into the system, he said. According to Perdew, the key to the process may be a receptor in the gut called Aryl hydrocarbon receptor, or AHR. The receptor helps the body regulate its reaction to certain environmental contaminants, as well as triggers other responses to toxin exposure. The researchers, who released their findings in the current issue of the Journal of Functional Foods, suggest that cruciferous vegetables, such as broccoli, brussels sprouts and cabbage contain an organic chemical compound called indole glucosinolates, which breaks down into other compounds, including indolocarbazole (ICZ) in the stomach.
When ICZ binds to and activates the Aryl hydrocarbon receptor (AHR) in the intestinal lining, it aids in maintaining a healthy balance in the gut flora and immune surveillance, and enhances host barrier function, according to the researchers. This may help prevent diseases, such as various cancers and Crohn’s Disease, caused by inflammation of the lining of the gut. According to Perdew, hyper-activating the AHR can cause toxicity, but using broccoli to activate the receptor locally, in the gut, rather than systemically might help avoid some of these problems. “Dioxin, for example, activates this receptor, and if you hyper-activate it with dioxin, it will cause toxicity,” said Perdew. “What we were interested in is: Could you locally activate the receptor naturally at a level that would cause only modest AHR activation in the gut, but not cause systemic activation, which could possibly lead to negative effects?”
The researchers used two genetic lines of mice in the study to focus on AHR. One line had a low ability to bind ICZ to AHR, while the other line had a high ability to bind ICZ to AHR. They added 15 percent broccoli to the diets of both groups of mice. After adding a substance that causes digestive problems, the researchers said that the mice with a higher ability to bind ICZ to the AHR were protected from a chemical that induced digestive problems, but the mice with the lower affinity suffered from the toxic insult.
For humans, the amount in the experiment would be equivalent to eating about 3.5 cups of broccoli each day, according to Perdew. “Now, three and a half cups is a lot, but it’s not a huge amount, really,” said Perdew. “We used a cultivar — or variety — with about half the amount of this chemical in it, and there are cultivars with twice as much. Also, brussels sprouts have three times as much, which would mean a cup of brussels sprouts could get us to the same level.”
Because people with certain digestive conditions like colitis, are often warned to avoid too much roughage in their diets, future research may include determining the best ways for people to consume broccoli, or other veggies with similar effects, to receive the same health benefits, without causing any other associated digestive problems from the fibrous vegetables.
Adapted from: Troy D. Hubbard, Iain A. Murray, Robert G. Nichols, Kaitlyn Cassel, Michael Podolsky, Guray Kuzu, Yuan Tian, Phillip Smith, Mary J. Kennett, Andrew D. Patterson, Gary H. Perdew. Dietary broccoli impacts microbial community structure and attenuates chemically induced colitis in mice in an Ah receptor dependent manner. Journal of Functional Foods, 2017; 37: 685 DOI: 10.1016/j.jff.2017.08.038
Nutrition Daily Nugget
Try a meatless meal each week. Think vegetable lasagna or a portabella mushroom burger! Vegetables and beans can add protein, fiber, and other nutrients to a meal.
Two recent studies concluded that the low-carbohydrate diet can increase lifespan. However, there is still plenty of controversy surrounding the Keto diet.
Has the fountain of youth been sitting on your dinner plate? Two new scientific studies independently concluded that a ketogenic diet increased lifespan and preserved memory and motor function in mice. For advocates of the diet, the results are another feather in their cap, but the question remains if the science really outweighs the hype for humans. “The conclusion we draw out of this is that it’s a robust effect,” said Dr. Eric Verdin, president and chief executive officer of the Buck Institute for Research on Aging and senior author of one of the papers, in a press release. “The two studies reinforce each other because they both show the same global effect on healthspan.”
Many are taking notice. This is a really exciting finding and long overdue,” Susan A. Masino, Ph.D., a professor of applied science at Trinity College in Connecticut, told Healthline. “[Ketogenic diets] mimic the metabolic state of fasting or caloric restriction — which has many similar benefits.” Masino has spent years researching the ketogenic diet, metabolism, and brain health — that is, how what we eat affects our brains.
How the studies were conducted
In Verdin’s study, some mice were fed between 70-90% of their daily food calories from fat. That was compared with control groups receiving only 13-17% from fat, with carbohydrate calories making up the bulk of the difference. The mice on higher fat diets had longer lives, lower midlife mortality rates, and performed better on tests pertaining to certain cognitive functioning. The results “clearly demonstrate that lifespan is increased in mice consuming a ketogenic diet,” compared with a control group, the authors wrote.
However, it’s impossible to say that such a conclusion could be reproduced in humans. As such, some experts are more measured in their assessment of these findings. Susan Weiner, MS, RDN, CDE, CDN, a dietitian and diabetes educator, agrees that the results are promising, but she cautions that it is still “too soon to recommend” the diet to many individuals.
Keto diet is controversial
The ketogenic diet has become pervasive in the United States in both popular culture and fitness circles for its myriad health benefits, but it remains contentious. The diet is based on the simple premise that when carbohydrate intake is drastically lowered or stopped entirely, the body must find a new primary source of energy. That source is fat. Ketosis is different from ketoacidosis, which is the leading cause of death of people with diabetes under 24 years of age.
Ketosis is identified by the presence of ketones in the bloodstream, a chemical that the body produces when it burns stored fat. The ketogenic diet has proven effective in helping to control seizures in some people with epilepsy. Advocates have also hailed its ability to help shed pounds. These new results, Masino said, are further proof of what some researchers, herself included, have believed for years.
However, any time a diet, scientifically backed or not, takes over Americans’ dinner plates, there are bound to be complications. A number of problems individuals can have with the diet have been pointed out in several articles. These include the risk of muscle loss, fatigue, and, of course, the many health issues associated with the yo-yo or fad dieting and with that story, many experts were at odds with each other.
However, Weiner and Masino both agree that for the average American, cutting down on carbs is probably a good thing (BUT, you DO want to make sure the carbs you do intake are whole grains!). “Most adults would benefit from reducing the overall amount of carbohydrate in their diet significantly,” said Masino. “Following a strict ketogenic diet is probably not necessary or realistic for most people unless they have very specific health goals.”
Trying to stay on the Keto diet
The “unrealistic” aspect of the ketogenic diet is that it can actually be difficult to maintain. It requires a strict adherence to a low-carbohydrate, high-fat diet, with little wiggle room for “cheat meals,” and absolutely no sweets or alcohol (O.K. I’m out for sure!). “In any kind of nutrition change there has to be sustainability,” said Weiner. For individuals who are out to lose weight, choosing a difficult diet can be taxing and may cause further setbacks rather than help.
“When you stop short, it does affect people feeling bad about themselves because they can’t keep up with it necessarily at the pace that it’s being recommended,” Weiner said. “So they feel it’s another failure in their trying to lose weight.” The ketogenic diet has been called “antisocial” because dining out becomes difficult, depending on how strictly one is adhering to the diet. “It can be very socially isolating,” said Weiner.
Even when preparing food at home, time management and cost are also factors for individuals who want to cook their own meals. “The social and economic situations affect this decision as well,” said Weiner. The bottom line is that individuals hoping to embark on a nutritional diet should be aware of the multifold ways in which it can impact their lives, beyond potential health benefits or harms. While this new research on the ketogenic diet is exciting, there still remains significant work to be done in human trials. Even then, it may not be beneficial for everyone.
However, as interest in it continues to grow among the general public, and the more informed decision an individual can make about their diet, the better. Weiner said proponents of this diet suggest that our current nutritional habits may lead to an increasing incidence of obesity, prediabetes, cancer and type 2 diabetes. More studies are needed to determine if the ketogenic diet should be recommended for those at high risk for developing these conditions. For most Americans, having to adhere to a strict ketogenic diet is more difficult than taking more simple dietary steps such as eating fewer sweets and carbohydrates, and eating more fresh vegetables.
Nutrition Daily Nugget
Use frozen or canned fish and poultry for a quick and easy meal! Choose the options canned in water and watch sodium content.
Eating fewer carbs does not mean giving up everything you love. A few easy changes can make a big difference in how much you consume. Instead of choosing carb sources loaded with sugar, fat, and calories, opt for more nutrient-dense alternatives filled with fiber, heart-healthy fats, and whole grains. You’ll be surprised at much you love the alternatives below and how delicious eating low-carb can be.
1. BBQ Baked Beans
GOOD: Beans are full of fiber.
BAD: Lots of sugar in the sauce—13g for a total of 32g carbs.
BETTER: Black beans with sautéed red bell pepper, jalapeño, lime, and fresh cilantro. 10g fewer carbs and an additional 1.5g fiber.
2. Salad Dressings
GOOD: You’re eating salad!
BAD: Dressing choices, such as honey mustard (one of my favorites!!) and raspberry vinaigrette contain roughly 7g refined carbs per 2 tablespoons, all from sugar. And most light or fat-free dressings add sugar to make up for fat.
BETTER: Opt for oil and vinegar-based dressings instead; you’ll get zero carbs and lots of heart-healthy fats.
3. Apples with Low-Fat Caramel Dip
GOOD: You’re eating apples—25g balanced carbs and 4g fiber.
BAD: That caramel sauce has 26g carbs in just 2 tablespoons, all from sugar.
Irritable Bowel Syndrome (IBS) is an extremely common gastrointestinal (GI) disorder that significantly reduces the quality of life. Treatment options for IBS have long been limited to symptom management. However, a new understanding of IBS has recently emerged, in which a dysfunctional gut–brain–microbiome axis is responsible for the development and progression of the disorder. Right now, you may be asking yourself “How does a dysregulated gut–brain–microbiome axis promote IBS and what therapeutic measures can be used to modulate this axis and reverse the course of the disease?” Well, let’s find out!
What is the gut–brain–microbiome axis?
IBS has an extremely high worldwide prevalence; it is estimated to affect approximately 10-25% of people in developed countries. Despite its vast influence, an understanding of the pathophysiology of this disorder has remained elusive for many years. In addition to abdominal pain, bloating, and abnormal bowel movements, IBS adversely impacts brain function and has been linked to psychiatric disorders such as anxiety and depression. Furthermore, research suggests that people with IBS have an altered gut microbiota compared to healthy individuals. These findings have led to the development of a new understanding of IBS, in which the interrelationship between gut symptoms, mental health, and the microbiome is mediated by the gut–brain–microbiome axis.
The gut–brain–microbiome axis connects the body’s central nervous system (CNS), which houses the brain and spinal cord, with the enteric nervous system (ENS) of the GI tract. This axis facilitates bidirectional neural, hormonal, and immunological communication between the gut and brain. The microbiome is the third key component of this axis. It serves as an intermediary between the gut and brain since the microbes it contains produce metabolites that relay messages to both organs. When the gut–brain–microbiome axis is in balance, the digestive system and brain function optimally. Conversely, dysregulation of this axis may initiate IBS and influence its progression and severity.
The microbiome is altered in IBS
Over the past several years, numerous studies have documented alterations in the gut microbiota of people with IBS relative to healthy people. This has led researchers to postulate that the microbiome may play a key role in the pathogenesis of IBS. In people with IBS, proportions of specific bacterial groups are altered and the diversity of microbial populations is reduced. Researchers have observed decreased levels of Lactobacilli and Bifidobacteria and an increased prevalence of pathogenic anaerobic organisms such as E. coli and Clostridia in fecal samples from IBS patients. In addition, IBS patients exhibit an increased Firmicutes-to-Bacteroidetes ratio.
There are several factors that may lead to microbiome disruption and the onset of IBS. These include antibiotic use, infection, diet, and stress. Stress is perhaps one of the more insidious factors that contribute to IBS; while dietary changes and treatment for gut infections can be relatively simple to institute, stress is an entirely different beast that must constantly be managed. However, the significance of stress and the psychological toll it creates in IBS cannot be understated, given our understanding of the gut–brain–microbiome axis.
The psychological toll of IBS
IBS sufferers have long understood the connection between their gut symptoms and mental health. Indeed, mental health issues such as anxiety and depression are a common comorbidity of IBS. However, this problem has only recently begun to receive the attention it deserves from the medical community, with the scientific discovery of neural links between the gut and brain in the gut–brain–microbiome axis. Further investigation into the psychological health of IBS patients has found that they exhibit a maladaptive stress response. This includes an exaggerated response to stress and an inability to appropriately shut down the stress response once the stressor is removed. IBS patients also demonstrate visceral hypersensitivity, a condition that increases the level of attention paid to gut symptoms, thus perpetuating anxiety about IBS. There is also evidence that people with IBS may experience stress-related deficits in cognitive function.
The enhanced stress response, anxiety, and altered cognition found in IBS patients may be due in large part to the influence of their gut microbes. There are several mechanisms by which gut microbes affect the gut–brain–microbiome axis. Via the axis, an altered gut microbiota can send neural signals from the gut to the brain, leading to the heightened stress response and increased visceral hypersensitivity characteristic of IBS. This promotes a sustained level of attention to the gut in IBS patients and an inability to “turn off” anxiety surrounding gut symptoms (I think this research is speaking to me 🧐). Gut microbes also alter the availability of tryptophan, an amino acid required to produce the mood-regulating neurotransmitter serotonin. Gut microbes influence the release of immune system mediators and glucocorticoids, which can heighten intestinal pain in IBS. Finally, pathogenic gut microbes can also initiate a proinflammatory state that increases intestinal permeability, resulting in the leakage of neuroactive metabolites from the gut into the CNS, where they have adverse effects on cognition.
Stress, in turn, has harmful effects on the intestinal microbiota. Stress increases intestinal permeability, allowing bacteria and bacterial antigens to cross the epithelial barrier into the bloodstream, inducing an immune response that alters the microbiome. Stress hormones, including epinephrine and norepinephrine, also increase the virulence of gut pathogens by enhancing the availability of iron, which the pathogens use to fuel their activities. Increased levels of gut pathogens may further exacerbate IBS.
Clearly, an imbalanced gut microbiome and an unhappy brain walk hand in hand. The complex relationship between the gut, brain, and microbiome in IBS creates a vicious cycle of intestinal symptoms, stress, and poor mental health. To break this vicious cycle, the gut–brain–microbiome axis must be repaired.
Repairing the gut–brain–microbiome axis to treat IBS
To successfully treat IBS, strategies must be employed that address each component of the gut–brain–microbiome axis. Modulation of the axis with dietary changes, prebiotics, probiotics, select antibiotics, and stress-reduction strategies offer a holistic means of treating IBS.
Diet and prebiotics
Significant positive changes can be induced in the gut–brain–microbiome axis through the implementation of dietary modifications and prebiotic supplementation. One dietary approach that has received substantial attention in the treatment of IBS is the low-FODMAP diet. Briefly, gut bacteria metabolize FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols), which include various types of fermentable dietary fibers, into short-chain fatty acids (SCFAs). High levels of two SCFAs, acetic acid, and propionic acid, have been associated with GI symptoms, anxiety, depression, and reduced quality of life in IBS patients. Reducing dietary intake of FODMAPs can lower levels of these SCFAs and therefore alleviate IBS symptoms.
However, research on the low-FODMAP diet for IBS conflicts with other studies suggesting that prebiotics, a type of fermentable fiber, improve both guts- and brain-related symptoms of IBS. The regular consumption of fructooligosaccharides (FOSs) has been found to reduce GI symptoms and improve quality of life markers such as anxiety and sleep in people with functional bowel disorders. Prebiotics also offer brain-health benefits; the intake of galactooligosaccharides (GOSs) increases hippocampal levels of the brain-derived neurotrophic factor, a protein involved in normal brain function, and N-methyl-D-aspartate (NMDA) receptors, which regulate brain plasticity and memory. More research is needed to understand the divergent responses to low-FODMAP diets and prebiotics in IBS patients. Clinically, practitioners should encourage patients to experiment with FODMAPs and prebiotics and find what works best for them.
Probiotics are another promising treatment option for IBS since they modulate both the gut and the brain components of the gut–brain–microbiome axis. Supplementation with Bifidobacterium infantis has been found to improve gut-related symptoms of IBS by reducing abdominal pain and bloating and normalizing bowel movements, while also inducing antidepressant effects through the augmentation of plasma tryptophan levels, increasing levels of the “feel good” neurotransmitter, serotonin. Bifidobacterium animalis is effective for promoting intestinal motility and reducing abdominal discomfort in IBS-C (constipation) patients. Lactobacillus acidophilus supplementation reduces visceral hypersensitivity to IBS by activating opioid and cannabinoid receptors, thus ameliorating intestinal pain and reducing hypervigilance to GI sensations. Finally, probiotic strains that repair the intestinal barrier may reduce the leakage of neuroactive metabolites from the gut into the systemic circulation, protecting brain function.
Mark Pimentel, a noted small intestinal bacterial overgrowth (SIBO) researcher, has found that up to 85% of IBS patients have SIBO. However, other research suggests that this may be an overestimation, due to the high false positive rate associated with the lactulose breath test used to diagnose SIBO. While not a cure-all, the eradication of SIBO using specific antibiotics, such as rifaximin, may benefit some cases of IBS.
Chronic stress perpetuates the vicious cycle of IBS by altering the gut microbiota, increasing gut pathogen virulence, and promoting intestinal permeability. The implementation of stress reduction strategies is crucial for breaking the cycle and restoring health to the gut–brain–microbiome axis. While there are many stress-reducing practices to choose from, three in particular—yoga, exercise, and mindfulness meditation—have demonstrated IBS-specific benefits. Yoga has exploded in popularity in recent years and has become the subject of extensive scientific investigation. A recent study found that a yoga practice consisting of postures and breathing exercises beneficially modulates gut and brain function by reducing sympathetic nervous system activity and increasing parasympathetic activity, making it an effective remedial therapy for IBS.
A generalized exercise program may also benefit the gut–brain–microbiome axis and reduce symptoms of IBS. Exercise increases GI motility, reduces intestinal gas retention, relieves stress, and increases the number of beneficial microbial species in the gut. Finally, mindfulness training is another beneficial stress reduction strategy for IBS. Mindfulness training (MT) promotes nonreactive awareness to emotional and sensory experiences, such as GI symptoms, and has been found to beneficially alter pain processing. An eight-week course of mindfulness training in women with IBS significantly reduced gut-focused anxiety and abdominal pain, thus breaking the vicious cycle of stress and intestinal symptoms.
A diagnosis of IBS no longer needs to be vague and frustrating for people. The newfound knowledge of the gut–brain–microbiome axis, and the variety of treatments that can be used to modulate it, offers IBS patients the possibility of a full recovery.
Research on a large sample of Canadians suggests that most people with celiac disease don’t know they have it.
Ahmed El-Sohemy, a professor of Nutritional Science at the University of Toronto, and his colleagues studied the bloodwork of almost 3,000 Canadians and found that one in 114 (or almost one per cent) had elevated antibodies that indicate they suffered from celiac disease, which causes gastric distress and other symptoms. However, the vast majority, almost 90%, were unaware they had the disease. The data was collected about a decade ago, just before public awareness about the potential problems with gluten skyrocketed. The study, published in the journal BMJ Open, is the first to screen for celiac antibodies in a Canadian population. It confirms previous research suggesting that Caucasians are more susceptible to celiac disease than other ethnocultural groups. Although the number of South and East Asians screened in the Canadian study was small, none were found to have the disease. Intriguingly, though, a genetic variant that puts people at high risk for celiac disease was almost as high in the South Asian samples as the Caucasian ones, suggesting that other factors could play a role in who goes on to develop the disease.
“This hopefully should just raise awareness that despite the gluten-free craze there are a lot of people who still don’t know they have celiac disease,” says El-Sohemy. “It’s important for people to understand that celiac disease is not a single clear symptom — it manifests itself in different ways. Symptoms could be fatigue, gastro-intestinal, or other problems. These symptoms are so diverse that doctors have a difficult time pinpointing the cause. Gluten intolerance is not usually the first thing that comes to their mind.”
Adding to the diagnostic confusion, reactions to gluten are not often immediate and acute, El-Sohemy says. “It’s not like lactose where you feel bad within a day after consuming it. Gluten causes damage to the intestinal lining, which results in malabsorption of vitamins and other nutrients, and the effects of those nutrient deficiencies are quite varied.” El-Sohemy believes people with a genetic susceptibility to celiac disease should consider blood tests to determine whether they have the disease if they present with any of the disease symptoms. His analysis of blood samples from Canadians of South Asian heritage suggests that genetic predisposition is only one piece of the celiac puzzle. Future research may focus on the timing of exposure to gluten as well as the role of gut bacteria.
As for why so many non-celiac sufferers feel better after giving up gluten, El-Sohemy speculates the real issue is “because they stopped eating heaping servings of pasta, white bread and other sources of processed carbohydrates.”
Adapted from: Joseph Jamnik, Christopher R Villa, Sirbarinder Bryn Dhir, David J A Jenkins, Ahmed El-Sohemy. Prevalence of positive coeliac disease serology and HLA risk genotypes in a multiethnic population of adults in Canada: a cross-sectional study. BMJ Open, 2017; 7 (10): bmjopen-2017-017678 DOI: 10.1136/bmjopen-2017-017678