There are several highly effective ways to treat fructose malabsorption – starting with a fructose malabsorption diet, some wonderful drugs with xylose isomerase, which let you eat whatever you want as long you take them before your meal, and some valuable tips to enhance fructose absorption. Already curious? Then read on.
Table of Contents
Get relief from fructose malabsorption symptoms with a low fructose diet
So let’s start with the low fructose diet. Maybe you think, that the solution might be eliminating any fructose-containing foods from the diet. But it is not that simple … or that awful.
Not every food that contains fructose may be a problem for you. Other naturally occurring sugars like glucose also come into play. As I describe under Facts, glucose aids the absorption of fructose along the small bowel. This means that some fruits can be eaten by fructose malabsorbers without annoying consequences when they contain more glucose than fructose.
Fructans are also problematic
Unfortunately, dietary exclusion of fructose in its purest form (as monosaccharide) is not the only thing you should do. You should also avoid fructans during that phase as you might also have difficulties in absorbing them. The role that fructans play in fructose malabsorption is still focus of several studies, but it is usually recommended to reduce their intake when having fructose malabsorption.
So what are fructans? Fructans are chains of fructose molecules, which normally end with a glucose unit. They can be found in several grains and vegetables, such as artichoke, leek, and onion. You can find detailed information on some problematic foods in the table.
| Food | Fructan content |
|---|---|
| Asparagus | 1.4 - 4.1% |
| Garlic | 9 - 16% |
| Globe artichoke | 2 - 6.8% |
| Jerusalem artichoke | 16 - 20% |
| Leek | 3 - 10% |
| Onion | 1.1 - 10.1% |
| Wheat bread (white) | 0.7 - 2.8% |
| Wheat flour | 1 - 4% |
| Wheat pasta | 1 - 4% |
Avoid sorbitol as it worsens fructose malabsorption symptoms
Sorbitol is a sugar alcohol that is often used as an artificial sweetener in sugar-free (“light”/diet) food. It naturally occurs in stone fruits, such as peaches, cherries, and plums, and often appears in dried fruits, like raisins and figs. Sorbitol worsens the absorption of fructose. Right now, the reason is not fully understood and still under investigation. One reason may be its laxative effect by drawing water into the large intestine. This stimulates bowel movement and reduces the time in which fructose can be absorbed within the small bowel. Another reason may be that sorbitol inhibits the GLUT5 transport protein.
So, what exactly should you do?
In general, for treating dietary fructose intolerance it’s best to restrict the intake of foods with high fructose and a fructose:glucose ratio > 1, fructans, and sugar alcohols like sorbitol. You don’t need to follow a strict low FODMAP diet, as you don’t need to avoid all FODMAPs, such as lactose, when having only fructose malabsorption.
Check out my Fructose Malabsorption Food List, my free nutrition guide, or one of the apps you can find under Helpful Resources for detailed information about what foods to avoid or eat without nasty consequences during a fructose malabsorption diet.
Studies have shown – and this is also my personal experience – that following a low fructose diet will bring you a significant improvement in symptoms [1]. After about 1 month of strict fructose malabsorption diet, I haven’t had any symptoms of cramps, pain, diarrhea, heartburn, and hypoglycemia anymore. And this is awesome!
Besides that, fructose is no essential nutrient for a human and is unlike glucose no preferred energy source for muscles or the brain. It will be converted into fat to a large extent. So, reducing the ingestion of fructose will also have other positive effects.
Here are the important phases of the fructose malabsorption diet
- Phase (Elimination): Try to eliminate fructose, fructans, sucrose, which is broken down by the human body into glucose and fructose, and sorbitol, which is also converted to fructose and glucose, for 4-6 weeks. I know it is hard, as fructose hides everywhere. But you should try it. Your fructose thresholds may somewhat increase by doing so.
- Phase (Testing): Then, gradually reintroduce small amounts of fructose to determine your new threshold. For example, start with fruits with a fructose:glucose ratio of 1 or less and low sorbitol content (e.g. bananas and grapes). Do not try to eliminate fructose completely from your nutrition after the first phase. Otherwise, your symptoms may worsen in the long term, as the production of the GLUT5 transport protein will be reduced.
- Phase (Low fructose nutrition): Your goal should be a fructose reduced nutrition without any fructose malabsorption symptoms after the first two phases. If you follow the first two steps properly, this can be a possible goal for you!
More useful rules for the fructose malabsorption diet
Avoid the following foods or reduce them:
- All dried fruits
- Stone fruits, which contain high amounts of sorbitol, such as peach and apricot
- Sugar-free (“light”) candies, gums and drinks, as they are sweetened with sorbitol or other sugar alcohols
- Fruit juices and sweetened soft drinks
- Sweetened milk products and yogurts
- Sweet baked goods, as they are often made with fructose or at least sucrose
- Foods with high fructan content, such as wheat, tomato paste, artichokes, onions, asparagus, and chicory
- Food that causes flatulence, like cabbage and legumes
Tips for an effective and more pleasant fructose malabsorption diet:
- Check out my Fructose Malabsorption Food List or one of the apps you can find under Helpful Resources for foods you are allowed to eat.
- Look for fructose-free recipes.
- Use alternative sweeteners for sweetening foods.
- Use onion/garlic infused oil to get that flavor back without causing symptoms.
- Eat only completely ripened bananas, as they have a better fructose:glucose ratio.
- Drink no cider and no sweet wines.
- Strictly avoid onions, as these are one of the greatest contributors to the fructose malabsorption symptoms.
- Read food labels carefully! (I was shocked to see onions, artificial sweeteners like sorbitol, and fructose on so many labels).
Keep in mind, that such a diet may lead to a deficiency of certain nutrients. So please consult a doctor or a nutritionist, if you are feeling bad during that diet or if you are just uncertain.
But now, I want you to take action and give it a try!
Do you have more useful tips? Please leave a comment below.
References
- Susan J Sheperd, M Nut Diet, APD*; Peter R Gibson, MD, MB, FRACP. Fructose Malabsorption and Symptoms of Irritable Bowel Syndrome: Guidelines for Effective Dietary Management, Journal of the American Dietetic Association, 2006:106:1631-1639.