Fructose malabsorption: the latest milestone on an epic digestive health odyssey
August 09, 2011
[Update (August 2016): Since writing this post in 2011 about an odyssey that began in 2009, our hypothesis that Amy has fructose malabsorption has been disconfirmed. I hope the information in this post will still be of use to those who have similar hypotheses, or confirmed diagnoses. Amy still suffers from periodic episodes of extremely painful abdominal cramping and some of the other symptoms described in the original post, but our current hypothesis is that these are psychosomatic, the result of life-long challenges in processing emotions such as fear and anxiety (similar in some respects to the patterns described by Scott Strossel in My Age of Anxiety). Others experiencing an epic digestive health odyssey might benefit from considering potential psychological or emotional factors - in addition to the physiological factors - that may be contributing to the suffering. We hope the information here will be instrumental in ameliorating, or at least explaining, some of that suffering, or at least offer some consolation that you are not alone in the intense pain, desolation and desperation that often arises on such a journey.]
After over two years of intermittently intense suffering, an interminable series of medical consultations with a variety of healthcare professionals, and numerous indefinite diagnoses, a dietician recently helped us converge on a new explanation for my wife's digestive health problems: fructose malabsorption (FM). Having experienced some relief from recently starting an elimination diet, it appears that Amy's small intestine does not properly absorb fructose and its many polymerized forms such as fructans, raffinose and other Fermentable Oligo-, Di- and Mono-saccharides And Polyols (FODMAPs). These are the sugars contained in many fruits, vegetables and whole grains. As we currently understand her predicament, when she consumes foods or drinks - or even chews gum - containing moderate amounts of fructose, a fructose-glucose ratio greater than 1:1, or any amount of other FODMAPs, they are not absorbed in her small intestine but pass through to her large intestine. The unabsorbed sugars feed bacteria, and the resulting fermentation leads to a range of symptoms that have included varying degrees of abdominal pain (3 extreme episodes involved pain "worse than childbirth", vomiting and trips to the emergency room), bloating, belching, diarrhea, decreased appetite and visceral hypersensitivity. During this time, she has also experienced skin rashes, muscle and joint pain, dry eyes, dry mouth, fuzzy head, fatigue and depression, but at this point we're not sure whether or how these symptoms may be related to fructose malabsorption.
Throughout this period, we have engaged in numerous medical consultations with Amy's primary care physician, colorectal surgeon, radiation oncologist, opthamologist, two gastroenterologists, an internist, and a rheumatologist (who referred us to the dietician), as well as various attending physicians during her visits to the emergency room. She has undergone blood tests, urine tests, stool tests, X-rays, CT scans, an MRI scan, a HIDA scan and a lip biopsy. Other diagnoses that have been considered (and eventually excluded) include gallbladder malfunction, Crohn's disease, Sjogren's Syndrome and chronic radiation enteritis (suspected as a delayed reaction to her 2005 anal cancer treatment). She has also been checked for celiac disease, gluten intolerance, H. pylori and intestinal parasites (all negative).
Candidates that have not yet been definitively ruled out include ileus, bowel obstruction and small intestinal bacterial overgrowth (SIBO) syndrome (in which the unabsorbed sugars are fermented in the small intestine rather than the large intestine). Mast cell activation syndrome (MCAS), a relatively unknown and ill-defined disorder in which mast cells precipitate an allergic overreaction (which in some people may include anaphylactic shock), is the most recent addition to the candidate list. Irritable Bowel Syndrome (IBS) is a much better known but not not much better understood disorder which has a high degree of symptom overlap with fructose malabsorption (and SIBO); we're note quite sure what to make of IBS, but Amy's IBS-related symptoms have significantly improved through the dietary management of fructose. Some of these conditions are suspected of being interrelated, and it may be the case that several of these diagnoses apply.
During a visit to Amy's gastroenterologist last Friday, he suggested that MCAS may be the genesis her FM/IBS symptoms - possibly triggered in response to an earlier gastrointestinal infection - and so she is preparing to add antihistamine and quercetin to her daily regimen to reduce the likelihood of future [over]activation. He also suggested that the rapid intestinal transit that was observed in an X-ray of her upper GI with small bowel follow-through may be a factor - fructose may not be absorbed in her small intestine because it simply isn't given enough time - and so he also recommended a daily dose of Imodium (Loperamide) to slow down the intestinal transit. I hope to have more to say about this trajectory in a future post.
Exploratory abdominal surgery was recommended by a few different specialists at earlier stages of her digestive health odyssey; thus far, concern over possible complications resulting from gastrointestinal surgery - which can introduce as well as reduce digestive problems - has steered her away from that path. However she did undergo hyperbaric oxygen (HBO) treatment at the Center for Wound Healing and Hyperbarics at Swedish Edmonds this spring to treat radiation enteritis, when that seemed to be the most likely diagnosis. HBO is a relatively unknown and minimally invasive treatment that appears to be effective for several conditions, and we were initially hopeful about prospects for improvement. Although she received excellent care over the course of her treatment, the lack of significant improvement in her digestive symptoms after 37 "dives" was a strong signal that radiation enteritis was not the correct diagnosis. She also underwent a course of Xifaxan (Rifaximin) antibiotic treatment for SIBO at the start of her HBO treatment, but the persistence of symptoms during that period lead us to believe that SIBO is/was not a primary factor.
Fructose malabsorption seems to be relatively unknown, at least in the U.S., and there are many aspects of the disorder that are still poorly understood. A review of studies on fructose malabsorption, most of which are based on results of hydrogen breath tests (HBTs), suggests that some level of fructose malabsorption may be present in more than a third of the "healthy" population in western countries, where high fructose corn syrup is increasingly used in popular consumer foods. HBT evidence of fructose malabsorption is present in a much larger proportion of those exhibiting symptoms associated with functional gastrointestinal disorders (FGIDs). However, there is some disagreement about the application and interpretation of HBTs, as well as the correlation between HBT results and FGID symptoms; there is also the risk of triggering severe reactions on the way to a "positive" test result, as some fructose must be ingested prior to measuring the hydrogen in the breath. In Amy's case, she has not taken an HBT, but we consider her body's positive response to a diet restricting fructose and other FODMAPS - and the negative response whenever she unintentionally eats even small amounts of high-FODMAP foods - to be strong evidence that fructose malabsorption is at or near the core of many of her digestive health problems.
Given the different tests, diagnoses and treatments Amy has undergone during this odyssey, one of the motivations behind composing this post is to share some of this experience in case it might help others who are unknowingly suffering from fructose malabsorption yet have only been tested, diagnosed or treated for other diseases or disorders. Amy is an indomitable e-patient - engaged, empowered, equipped and increasingly expert in her own medical care - and I'm hoping her journey may help inform or inspire others. If not for her perseverance, she may have undergone other, potentially more invasive or risky treatments, and might still be suffering [more] from the often debilitating symptoms.
That is not to say she is not still suffering; the source of suffering has simply shifted from severe reactions to food to severe restrictions on food. There is no known cure for fructose malabsorption, and it appears the most effective treatment is an austere low-FODMAP diet, devoid of most fruits, vegetables, grains and other sources of sugars that can feed the bad bacteria. Based on some recent negative food reactions, we suspect that Amy may also be lactose intolerant - lactose being another sugar - and so she is also currently avoiding all dairy products. Years ago, she discovered that foods high in saturated fat triggered negative reactions - her digestive health odyssey actually began decades ago - so those foods were already eliminated from her diet.
At this point, nearly all the things she most enjoys eating and drinking - including many fresh fruits and vegetables, whole grains, cheeses, chocolate, wine and beer - are now on the "avoid" list. Many activities and places that used to bring her joy - such as growing fruit and vegetables in her garden, exploring farmers' markets, trying new restaurants - are now also on an "avoid" list, serving as depressing reminders of the life she enjoyed until recently. As one among many examples, the strawberries in her garden [shown in the photo at the right] recently achieved optimal ripeness and were ready for harvest, and although they are a generally "safe" food in the low-FODMAP diet, she had a negative reaction to eating a store-bought strawberry a few weeks ago, and so she could only pick but not eat them. One of the many puzzling dimensions of this disorder is why she can no longer tolerate so many nutritious foods she used to eat regularly; it's as though some kind of switch has been flipped. While we have found no evidence that fructose malabsorption is a life-threatening disorder, it is certainly proving to be a lifestyle-threatening disorder, and the psychological adjustments are at least as challenging as the physical ones.
The good news is that after six weeks on the diet, many of her physical symptoms have been greatly alleviated; the bad news is that many of the generally "safe" foods she has tried to re-introduce so far have re-triggered negative physical - and emotional - reactions.
Margaret Mead famously observed that
Always remember that you are absolutely unique. Just like everyone else.
This individual and collective uniqueness is a significant factor for those suffering from fructose malabsorption ("FMers") and following a low-FODMAP diet, in that foods that are safe for one FMer - or even most FMers - may not be safe for another FMer (e.g., strawberries). Further complicating matters, heating (cooking) and cooling (refrigeration) affects the chemistry of foods, as does ripeness (in the case of fruits and vegetables), and so foods that may be safe in one state may not be safe in another. Foods that might be safe in isolation may not be safe when consumed soon before or after other foods that also might be safe in isolation. The set of safe foods for a given FMer can also change over time. We keep hoping it will get better, that her gut will heal and she will eventually succeed in reintroducing some of the eliminated foods. It appears that "getting better" involves some combination of radically adjusting the diet and the associated gustatory expectations and desires, as well as managing stress through exercise and mindfulness meditation ... and practicing a great deal of patience.
Amy is currently at the most restrictive phase of the low-FODMAP diet. She has eliminated everything but fish, chicken, lean beef and pork, oatmeal, white rice, rice pasta, rice crackers, quinoa, buckwheat, banana, grapefruit, portabella mushrooms, mustard greens, Swiss chard, spinach, almond milk, an assortment of seeds, oils and nut-based butters, and decaffeinated coffee. The photo on the right shows the single shelf containing all of the non-perishable foods she can safely eat at this stage [since taking the photo, we discovered that the shallots in the bowl at the right are not low-FODMAP and have been eliminated]. We hope this is a temporary low, and she will eventually reach a stage where we will need more than one shelf to store her food.
After achieving a state of greater digestive balance in the first two weeks, Amy started experimenting with reintroducing other generally "safe" foods (e.g., blueberries), several of which have resulted in a mostly mild recurrence of symptoms. Just this week, she had an extreme bout of abdominal pain - almost on a par with the bouts that brought us to the emergency room - that, as far as we can determine, resulted from eating a few sea salt & cracked pepper flavored potato chips. We later discovered that one of the other seasonings listed in the ingredients included onion powder, which is on the low-FODMAP "avoid" list, reminding us of how diligent and vigilant we need to be about checking ingredients.
Due to the cumulative effects of unabsorbed sugars in the gut, low-FODMAPpers are advised to wait 72 hours between experiments, so as to be able to correctly assess the credit (or blame) for any symptom recurrence. Another recent failed experiment occurred after eating 1/2 of a leftover baked potato (with a small amount of "safe" margarine and no skin) a few weeks ago. The next day, shortly after eating her standard breakfast of plain oatmeal, she experienced the waves of sharp abdominal pain that characterized her worst reactions. We have since learned that starch can be problematic, at least in the early phase of the diet, and that refrigerating potatoes increases their starch content. We also discovered that oatmeal contains starch, so the abdominal pain may have been triggered by an inadvertent starch overload. We hope to redo the experiment with freshly cooked potatoes, which are a generally "safe" food, during an otherwise low-starch period, in the hope that they will prove safe for her to eat again.
Amy sometimes fears that she will never be able to reintroduce eliminated (or new) foods, regain weight or acquire the nutrients - through food - that her body needs. She has been compensating for nutritional deficits through supplements including UltraClear Medical Food and calcium citrate, and has also been experimenting with the probiotic VSL#3; many supplements contain FODMAP ingredients, so she needs to be careful with those as well. Over the past 2 years, she has lost 20 pounds (9 kg) and now weighs 110 pounds (50 kg); she stands 5'8" (173 cm) tall, yielding a body mass index of 16.7, well below the "underweight" threshold of 18.5. This is particularly worrisome because none of the foods that have proved safe for her to eat [yet] are foods that can help her gain weight. Even at the worst / lowest point during her recovery from radiation and chemotherapy treatment, she weighed 117 pounds (53 kg). The lack of absorbed nutrients is likely contributing to osteopenia bordering on osteoporosis. On top of all this, her hair has also been thinning [again] throughout this time. The photo at the right was taken a little over a year ago, on the 5-year anniversary of her successful cancer treatment; little did we know then that this would represent a relatively brief crest amid the sporadically crushing waves of health challenges.
When Amy was diagnosed with anal cancer in 2005, the early stage of the diagnosis gave us confidence that there was a high probability the treatment would be successful (it was), and the side effects would eventually subside (they have). When she was diagnosed with multiple sclerosis in 1986, the long gaps between her initial exacerbations gave us hope that she would not suffer the steady and progressive deterioration that some with MS experience (she has not). The fructose malabsorption diagnosis - and low-FODMAP dietary treatment - have left her feeling more isolated and depressed than any prior health challenge. It often seems like no one - at times, including me - fully grasps the magnitude of the restrictions she may be facing, possibly for the rest of her life.
As I noted above, one reason I am writing this post is to share her (our) experience of this odyssey, in the hope that it might help others become more aware of a condition that may be widely experienced (to varying degrees) and not [yet] widely diagnosed or appropriately treated, especially in the U.S. Our hope is that we might save other sufferers some of the pain, time and money - not to mention fear, uncertainty and doubt - that we have experienced over the past several years. I plan to share more of the ongoing odyssey in future posts, similar to the "cancer counterinsurgency" series I posted during Amy's anal cancer diagnosis, treatment and recovery (which has generated more comments and email than anything I've written). We've discussed the prospect of Amy starting her own blog to catalog her journey, but for now, she is focused more on learning than sharing, as she adopts and adapts new ways to nourish and nurture herself through nutrition, exercise and stress reduction.
I'll finish off this post with a few resources that I / we have found particularly helpful:
- Heidi Turner, RD, is the Medical Nutritional Therapist at Seattle Arthritis Clinic, which we first visited when Sjogren's Syndrome was a candidate diagnosis (subsequently ruled out via lip biopsy). Heidi helped us converge on the fructose malabsorption diagnosis, and she has continued working with Amy through office visits, telephone consultations and email to help her navigate to a safe, if severely restricted, baseline diet and gradually experiment with reintroducing eliminated foods. Her web site offers a number of resources to support the elimination diet (which can be applied or adjusted to support other digestive disorders).
- The Irritable Bowel Syndrome Self Help and Support Group (IBSgroup.org) has a number of high signal-to-noise ratio forums; the thread on Printable FODMAP diet chart for your convenience, in particular - especially the posts by pseudonymous IBSGroup user Common Response - has more valuable online information about the experience of fructose malabsorption, lactose intolerance and a low FODMAP diet than anything we've encountered.
- A blog maintained by A.V. Thompson has a number of posts describing her insights and experience with fructose malabsorption - including numerous baking experiments - from January 2008 thru May 2010; she recently started posting again after a 1+ year hiatus, and I hope she will continue sharing her journey(s). Her post - and others' comments - on What is Fructose Malabsorption Disorder? is very helpful, as is her Google site on "fructmal".
- A collection of pages on Information on Fructose Malabsorption compiled by an anonymous FMer in UK, including tips for living with fructose malabsorption, is also very useful.
- The Eastern Health Clinical School of Monash University in Australia appears to be at the forefront of clinical research into fructose malabsorption, FODMAPs and other related issues involving gastroenterology and nutrition. Two researchers from Monash - Peter Gibson and Sue Shepherd - were the first to expand the focus from fructose to FODMAPs [Personal view: food for thought – western lifestyle and susceptibility to Crohn's disease. The FODMAP hypothesis. Alimentary Pharmacology & Therapeutics, 21(12):1399–1409; June 2005]. Another article they co-authored, along with other colleagues at Monash, is the single most useful scholarly overview I've found yet on fructose malabsorption [Gibson, PR, Newnham, E, Barrett, JS, Shepherd, JS, and Muir, JG Review article: fructose malabsorption and the bigger picture. Alimentary Pharmacology & Therapeutics, 25 (4): 349-363, Feb 2007]. A more recent paper by Gibson & Shepherd, Evidence-based Dietary Management of Functional Gastrointestinal Symptoms: The FODMAP Approach (Journal of Gastroenterology and Hepatology, 25(2):252-258, Feb 2010) is also quite useful.
- Sue Shepherd also has a dietician practice in Australia, Shepherd Works, and has posted many resources regarding fructose malabsorption, FODMAP intolerance and other digestive disorders such as celiac disease, irritable bowel syndrome and lactose intolerance. These resources include research articles and books such as the The Low FODMAP Diet and The Food Intolerance Management Plan [unfortunately, the shipping charges from Australia may make these prohibitively expensive for some prospective American readers].
- Another Monash University researcher, Jaci Barrett, is affiliated with another Australian group of dieticians, Diet Solutions, with clinical experience and research involvement in fructose malabsorption, FODMAP intolerance and a number of other digestive disorders. Jaci was kind enough to send me a paper she co-authored with Peter Gibson [Clinical Ramifications of Malabsorption of Fructose and Other Short-chain Carbohydrates, Practical Gastroenterology, Aug 2007] when I contacted her seeking clarifications regarding references in the Wikipedia entry for fructose malabsorption; the figure at the start of this post is from that paper.
- An August 2010 article on The FODMAPs Approach — Minimize Consumption of Fermentable Carbs to Manage Functional Gut Disorder Symptoms in Today's Dietician by Boston-based Kate Scarlata offers a good overview that balances breadth and depth and may be more generally accessible to a non-clinical audience. She is also the author of The Complete Idiot's Guide to Eating Well with IBS, which includes coverage of fructose malabsorption and FODMAPs and has several garnered many positive Amazon reviews, including several from other dieticians.
- IBS--Free At Last! (IBSfree.net) is a blog by Patsy Catsos, a dietician in Portland, Maine, that seems particularly attuned to FODMAP-related issues. She is also author of the similarly titled book, IBS--Free at Last!: A Revolutionary, New Step-by-Step Method for Those Who Have Tried Everything. Control IBS Symptoms by Limiting FODMAPS Carbohydrates in Your Diet. Unfortunately, due to Amy's suspected lactose intolerance, the low-FODMAP recipes on this blog - and most other low-FODMAP recipe sources we've discovered thus far - are off limits for her.
- Gabor Mate's 2003 book, When The Body Says No: Understanding the Stress-Disease Connection, makes a compelling case for the the role stress plays in the onset and progression of many chronic conditions such as IBS, cancer, multiple sclerosis, arthritis, diabetes and heart diseases. The author, a practicing physician, also emphasizes the importance for doctors and other medical professionals to pay attention to patients' life stories - not just their symptoms - in their efforts to promote effective healing.
- Jon Kabat-Zinn's 1990 book, Full Catastrophe Living: Using the Wisdom of Your Body and Mind to Face Stress, Pain, and Illness, and the associated mindfulness meditation practice audiotapes and CDs, offer very helpful guidance in managing the stress associated with the diagnosis and treatment fructose malabsorption (and many other maladies).
I want to emphasize that neither Amy nor I have any formal training in medicine, nutrition or biochemistry; the information shared here is based on the personal experience of a long-time sufferer and her spouse. Based on our interactions with various health care professionals over the last several years and my own reading of over 40 peer-reviewed articles in medical research journals over the last several weeks, we appear to be at the beginning stages of a very steep learning curve involving a condition - or perhaps several - that do not seem very well studied or understood. I also want to highlight the fact that we are still not sure whether fructose malabsorption is the primary diagnosis or is secondary to other conditions (such as MCAS, IBS and/or SIBO). This is why the subtitle of this post is the latest milestone - vs. diagnosis - on a digestive health odyssey ... and our epic journey continues.
While we expect - or hope - that most people will never experience the symptoms of fructose malabsorption, or the challenges of the restrictive diet used in its treatment, we also hope that those who are suffering from these symptoms - or know someone else who is - and thus may be candidates for the diagnosis and dietary treatment, might benefit from this summary of our experience thus far, and seek out personalized care and guidance from appropriately trained health care professionals.