Fructose Malabsorption: The Only Guide You Need
Today you're going to learn about:
First, I'll explain to you what Fructose Malabsorption is.
Then you'll see what the symptoms of Fructose Malabsorption are.
Followed by how you can get diagnosed and finally I'll tell you what foods are low in Fructose.
Let's dive in!
Skip to a section:
- What is Fructose Malabsorption?
- What is Fructose?
- What are the Symptoms of Fructose Malabsorption?
- How is Fructose Malabsorption Diagnosed?
- How Does the Fructose Test (hydrogen breath test) Work?
- What is the Treatment for Fructose Malabsorption and Can it Be Fixed?
- What Food is Low in Fructose?
- Fructose Malabsorption Food List for Low FODMAP diet
- Low FODMAP Food Manufacturers
- Our Favourite Certified Low FODMAP Products
What is Fructose Malabsorption?
Fructose malabsorption is a condition where the small bowel struggles to absorb the fructose we eat causing digestive symptoms like bloating.
Therefore, Fructose malabsorption is a digestive disorder in which the complete absorption of fructose does not take place in the small intestine.
This poorly absorbed fructose moves through into the large bowel, where it gets fermented by the natural flora present in the intestinal tract.
The fermentation by bacteria produces gas and other gastrointestinal symptoms.
As our body does not require digestive enzymes to digest and absorb fructose in small intestine.
In a normal, healthy persons, only about 25-30 grams of fructose are absorbed at one time.
However, in case of people with fructose malabsorption, less than 25 grams of fructose is absorbed at any given time.
This inadequately digested fructose reaches large intestine where it combines with water due to its osmotic effect.
Here, it is rapidly propelled into the colonic lumen where luminal bacteria ferment fructose to carbon dioxide, hydrogen and short chain fatty acids.
This leads to physiological consequences, including increase in osmotic load, change in gastrointestinal motility, alteration in gastrointestinal flora, and rapid bacterial fermentation.
The clinical significance of these events varies from individual to individual depending upon the response of the bowel to such changes.
Formerly known as dietary fructose inheritance, Fructose malabsorption is completely different from fructose intolerance.
Fructose intolerance is a rare, hereditary disease in which the liver enzymes that break down fructose are deficient.
If left untreated, it can be a potentially fatal condition.
Its estimated that nearly 35 percent of the population struggle to absorb fructose properly, but before we understand more about fructose malabsoprtion - we need to understand what Fructose is!
What is Fructose?
It is a single molecule sugar which many people cannot effectively absorb.
This poorly absorbed small carbohydrate act as dietary fibre or prebiotics, also known as FODMAPs (Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols).
Other poorly absorbed sugars included in FODMAPs are lactose, sorbitol, fructans, galacto-oligosacchrides and mannitol.
When the fructose sugar is not properly absorbed in the small intestine, it reaches large intestine where fermentation occurs, and fructose is converted in to fatty acids.
These fatty acids cause gastrointestinal symptoms like bloating, gas, constipation and diarrhea.
What are the Symptoms of Fructose Malabsorption?
The symptoms of fructose malabsorption are actually similar to those of lactose intolerance, food allergies and irritable bowel syndrome.
Common symptoms observed immediately after consumption of fructose-rich foods are:
- Bloating and distension
- Diarrhea or constipation
- Fatigue or tiredness
- Stomach pain or indigestion as a result of muscle spasm
- Brain fog/ negative emotions
- Nausea or vomiting if large quantities of fructose are consumed
Long-term fructose malabsorption symptoms can include:
- Craving for sugar, and in rare case aversion to sugar
- Poor absorption of minerals and vitamins, resulting in anaemia, malabsorption and poor general health.
- Difficulty in gaining weight
- Early signs of mental depression
- Poor nails, skin and hair
- Osteopenia or osteoporosis, caused due to high fructose levels in the diet.
How is Fructose Malabsorption Diagnosed?
Typically a doctor will refer patients who express symptoms similar to the above for a hydrogen breathe test.
The hydrogen breath test is the fundamental diagnostic test for assessing the identification of dietary fructose malabsorption.
This simple and non-invasive method is a reliable way to diagnose fructose malabsorption.
How does the fructose test (hydrogen breath test) work?
The patient is asked to drink 25 to 30 grams of fructose (dissolved in water) on an empty stomach.
Hydrogen levels are measured at 30 minute intervals in the exhaled breath for the next three hours.
Hydrogen can only be found in the exhaled breath if the fructose is not entirely absorbed by the body.
Hydrogen is released when the bacteria ferment the poorly digested fructose in the large intestine.
The produced hydrogen reaches the lungs via the circulatory system, where it is exhaled into the testing device.
If you suspect that you have Fructose Malabsorption, you should go speak to your doctor about obtaining a refferal for a hydrogen breathe test.
You will most likely be referred to complete a lactose test as well ( I was) given the symptoms of fructose and lactose intolerance can be very similar.
The hydrogen breathe test will most likely be completed at your local hospital or specialist testing clinic.
Alternatively, there is a range of home testing kits for fructose (and lactose) malabsorption that you can purchase online, complete in your home and have the results tested by a laboratory.
I've included a list of online fructose testing laboratories below:
Online Fructose Testing Kits:
- Quintron Fructose Home Breathe Test kits - Home Breathe test kits for fructose malabsorption detection.
- GastroLab Gut Diagnosis - Offer a range of test kits posted to anywhere in Australia.
Another method for diagnosing the symptoms of fructose intolerance is by following an elimination diet.
A diet whereby the patient must elimate all foods containing fructose for 6 weeks.
If the symptoms disappear after eliminating fructose containing foods from the diet, fructose malabsorption is confirmed.
What is the treatment for Fructose Malabsorption and Can it Be Fixed?
Typically the treatment for fructose malabsorption is the low FODMAP diet.
The best resource I've been able to find is Sue Shepherd and Peter Gibson's book "The Complete Low-Fodmap Diet" (see above).
There is no permanent cure for fructose malabsorption, but the condition can be managed by limiting the amount of fructose that is consumed.
The goal of the treatment is to eliminate or drastically reduce symptoms, restore normal digestion and maintain subsequent health and longevity.
Once you are symptom-free for months, you can gradually reintroduce small amounts of foods that previously caused problems.
The dietary strategies to assist with minimising symptoms include:
- Avoid foods containing excess fructose;
- Reduce the fructose load; and
- Avoid foods that contain fructans (Fructans are chains of fructose molecules which end in a glucose molecule).
Foods that should be avoided by people with fructose malabsorption include:
- Foods containing more than 0.5 grams of fructose per 100 grams of glucose.
- Foods containing more than 0.2 grams of fructans per serving.
- Foods with high fructose to glucose ratio higher than 1.0
- Foods rich in sorbitol
- Foods containing high amounts of fructose content like corn syrup.
What food is low in Fructose?
Below, we have compiled a list of foods that most people with Fructose Malabsorption find "Okay to eat" and the foods that are "Best to avoid" eating completely avoided.
Please keep in mind that this list is not extensive and should only be used as a starting point to finding the foods that are causing symptoms of Fructose Malabsorption.
Different people will find that they have different tolerances to different food types.
Fructose Malabsorption Food List for Low FODMAP diet
Okay to eat
Best to avoid
Note - if you are changing diet to manage your fructose malabsorption intolerance you should do so with the supervision of a dietician who has experience with IBS symptoms.
This will ensure that you are receiving the right amount of nutrients and vitamins in your diet.
A full list of foods that contain fructose can be found here - Food Standards Australia.
Please keep in mind that foods with fructose to glucose ratio of less than 1, should be fine to consume.
Low FODMAP Food Manufacturers
As more and more people are being diagnosed with Fructose Malabsorption specialist food manufacturers are begining to produce food products that are suitable for people following the low fodmap diet.
Brands that make Low FODMAP foods include:
- Fody Co - all products have been certified as lowfodmap by Monash University.
- Casa De Sante - sells low fodmap products for people with IBS and digestive sensitivies.
Our Favourite Certified Low FODMAP Products
This is the perfect starter pack to help ease you into the low fodmap diet.
The starter pack by FODY CO includes: Ketchup, Salsa, Pasta Sauce, Thousand Island Dressing, Taco Seasoning and nut based snack bars.
All of the items are tested as Low Fodmap certified so you don't have to worry about eating some onion or garlic!
Knowing what spices to use in your cooking can be a little challenging on the low fodmap diet as often garlic and onion are included in our favourite mixes!
This 5 spices starter kid includes: Italian Tuscan Herb Mix, Indian Spicy Hot Seasoning, Mexican Seasoned Mix, Lemon Herb Seasoning and a BBQ Rub.
This product is low fodmap certified and is also gluteen, vegan and salt FREE!
These two products should give you an idea of the taste of their products and you can order more of the ones you like from there!
Congrats - you've made it to the end of my fructose malabsorption guide!
I'd love to hear about what your experience with Fructose Malabsorption has been - please leave any question or comments below.
Top Photo Credit: http://www.sxc.hu/profile/forwardcom