What is Fructose Malabsorption?

The simple answer would be that FM is when the intestines are unable to properly digest fructose, leaving a person with various health problems.

More complex?

Our intestines are only able to digest so much fructose per sitting.  When one has fructose malabsorption that means that they are not able to digest as much as the average person can.  If a person is not able to digest 25 grams of fructose per sitting they are considered to have FM.  25 grams of fructose is a lot of sugar in a sitting.  There are varying degrees of FM sensitivity, some can only absorb about 1 gram of sugar per serving and others can absorb closer to 20-25g. 

Fructose is a simple sugar called a monosaccharide (from the greek meaning single sugar) found in many plants and often called fruit sugar.  The body uses monosaccharide for energy.  Pure, dry fructose is a very sweet, white, odorless, crystalline solid and is the most water-soluble of all the sugars.  Fructose occurs naturally in fruits, some vegetables, honey, sugar cane, sugar beets, wheat, and some other plants.  Fructose is found commercially in sucrose (table/white sugar) and high fructose corn syrup (knows as fructose/glucose in Canada), as well as crystalline fructose.

A person with FM has an inability of the small intestines to break down fructose into smaller molecular fragments for digestion.  The fructose ends up progressing down to the large intestines where bacteria breaks it down into methane gas, hydrogen gas, carbon dioxide and fatty acids.    This results in bloating, diarrhea, flatulence, abdominal pain, nausea and lethargy.  Symptoms generally appear two to 24 hours after ingesting fructose-containing food.  Because this usually causes diarrhea this also results in important vitamins and minerals being lost and over time a person can develop nutritional deficiencies,  commonly calcium and iron, but long term can lead to anemia and osteoprosis.

It should be mentioned that Fructose Malabsorption was previously called Dietary Fructose Intolerance and is still sometimes referred to as this.  Fructose Malabsorption is different then Heriditary Fructose Intolerance (HFI).    In HFI a person lacks the enzyme to break down fructose, thus it can cause liver and kidney problems, as well as be fatal. Fructose Malabsoprtion (FM) although not always pleasant it is not life-threatening and is easily manage by diet. In HFI you must adhere to a very strict fructose-free diet whereas with FM you can learn to adjust your diet according to what you can tolerate.

Links to further reading:

• http://en.wikipedia.org/wiki/Fructose_malabsorption
• http://en.wikipedia.org/wiki/Fructose
• http://www.healthhype.com/fructose-malabsorption-cause-symptoms-and-diagnosis.html
• http://www.livestrong.com/article/285512-what-is-fructose-malabsorption/
• http://www.foodintolerances.com.au/food-intolerances-fructose.aspx
• http://glampress.glam.com/blogs/healthhypecom/fructose_malabsorption_cause_symptoms_and_diagnosis
• http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001399/
• http://en.wikipedia.org/wiki/Hereditary_fructose_intolerance

Symptoms of Fructose Malabsorption?

The symptoms of FM are very widespread, but the most common ones are:

• bloating
• (smelly)  flatulence
• diarrhea
• constipation
• stomach pains/cramps
• acid reflux/indigestion/heartburn

The other common symptoms that people will complain about are:

• vomiting
• brain fog/fuzzy head/difficulty concentrating
• aching eyes
• fatigue 
• headaches
• mood disturbances
• depression
• trouble sleeping
• joint pains

(*italics denotes symptoms that I get)

If you look at this list you can see that it would be rather hard to come to the conclusion that FM is what is ailing a person by these symptoms. Those with FM are usually diagnosed with IBS, and unfortunately that's as far as the doctors go.  I’m not sure why they find it acceptable to just diagnose a person as having IBS.  That to me is like saying “you have cancer” and leaving it at that.  Cancer is a broad term used to explain a larger variety of illnesses, but to tell someone they have cancer does not tell them anything about the cancer they have, what form they have, how they got it, how to treat it, etc.  IBS is just a broad term that tells a person they have something going on with their intestines/bowels.  But what is causing the irritation?  How do you treat this irritation?  IBS classifies the symptoms but does nothing to help a person fix the cause of the symptoms.  I don’t need a doctor to tell me I have IBS, I know that, but what I need to know is what caused this syndrome and how am I going to treat it. 

Many people with FM are left undiagnosed for years before they finally stumble across FM, often after having tried many different medications,  diet changes, and evaluated what they are eating for quite some time.  Some people are fortunate enough to have a doctor who is aware of FM and will send them for the test, but many doctors are not aware of FM or that there is a test for it.  There are also many doctors who believe that there is no such things a FM (leaving patients extremely frustrated and “lost”).  There is slowly becoming more awareness of FM, but it is still widely unheard of.  While there is a test for FM the ultimate test is the diet, as this is what will truly tell you the severity of your FM, and if you couldn’t have the FM test done, then it will help you to determine if FM is what is ailing you.

Managing your low-fructose diet is done by managing your symptoms.  When the symptoms are under control the diet is under control (that is if there aren’t other things to factor in also, which there often is).

Where to Start?

It’s hard to even know where to begin.  I remember the excitement of getting a diagnosis for Rebecca, and then the discouraging feeling when I began to read and research and couldn’t come up with any very consistent information.  I remember reading and reading and trying to put it all together … even now I have to keep reading and trying to understand since it’s a disorder that continues to change as more research is being done.  What we thought was okay at one point is no longer considered okay (e.g. rye) and what we were told to avoid before might be said to be allowed now (e.g. green beans).  But in the end they can say all that they want but it it still comes down to your individual sensitivity which can just leave you thoroughly  confused as so many things can factor into that sensitivity (sensitivity to other foods, medications, other illnesses, etc).  It’s been over a year of seriously trying to figure out my diet and I’m still very confused at times.  I know this sounds discouraging, but I also know that if I were a bit stricter I might be able to put a better finger on things.  At the same time I also realize that I have Wacko Steph Syndrome (which simply means nothing with me ever makes sense or follows the books) so I’m not a very good example.  Everytime I think I have it figured out something else changes things making me feel discouraged and lost (e.g. a recent change in medication).  I just *sigh* and keep trudging along reminding myself that while I don’t have it all figured out I’m a long ways ahead of where I used to be and this means I feel better then I used to.  Focus on the positive and deal with the negative.

That all being said I have to say that I do not have an extreme case of fructose malabsorption (FM).  I would say that in our house we are moderately sensitive.  We would be most sensitive then those who are mild and just have to avoid the worse fructose foods, but we are not so extreme as some who have a very very limited diet.  We are able to eat a good variety of food, especially since we removed wheat from our diet.  We found that wheat (fructans) was our biggest issue and once we removed that we were better able tolerate more fruits and vegetables.  So while we’re not the mildest case we are definitely not severe.  People who know us may think our diet is difficult and we have some severe sensitivity, in comparison to the many other FM people I have heard from, communicated with, I know that we have it pretty easy.

As I write my blog I want to remind people that I am not a doctor, I have no medical background and am not very good at understanding biology … although I have certainly had my abilities tested and trained in this area in the past years.  I am simply a FM sufferer and mother who wants to enjoy eating while keeping unwanted symptoms away so that we can feel healthy and enjoy our life.  My goal is to simply have a place where I can store information, for myself to go back to and for others to learn from.  A place where the information is gathered.  I realize that it is always best for one to do their own research, but this will provide a starting base and as much as possible I will try to provide links so others can read and learn from what I have read.  This will help me to remember where I found information as well.  So often I read something and keep it in mind when trying to figure things out, but then can’t remember where I read it to refer back to it. 

Welcome to my blog.  I am going to assume that since you are here you, or someone you know, has FM.  I am sorry that you have to deal with this, but with time you will better understand how to eat healthy and what your body can tolerate and this will help you to feel better.  It may seem overwhelming at first, but with time you will get a grip of it and feel more confident in determining what you can and cannot eat, what you can tolerate, how much you can tolerate, etc.  While FM sucks … it is manageable and treatable.