When I cast my mind back to my very first surgery, I remember all sorts of ‘plumbing’ issues but was told it would take a while for my adjusted plumbing to repair and do its work once more. It’s not gone fully back to normal, but I accept minor side effects of getting rid of cancer (metastatic with small intestine NET primary).
My diet is slightly different nowadays as I endeavour to return to that normality, and I have a good handle on what makes me move faster AND slower. Constipation is not good either, so I try to find a middle ground.
I started taking pancreatic enzyme replacement therapy in 2018 and often use that to offset a meal containing more fat than other meals, similar reducing dosages for lower fat meals.
I do like the odd sweet (candy), but not a big fruit eater if I was to be honest but I do eat a fair amount of well-cooked broccoli (well-cooked to avoid any high residue issues). After a comment in my private group about fructose intolerance, I set about researching that subject to be able to document it in this blog. I found some potential linkages to NET treatment. I think this is just another piece of the Diarrhea jigsaw coming the consequences of surgery and/or side effects of treatment.
Fructose is a natural sugar that occurs naturally in fruits, fruit juices, certain vegetables, and honey. In these forms, fructose sugars can be part of a healthy diet. However, fructose is also a component of high-fructose corn syrup (HFCS), which manufacturers make from corn starch and add to not so healthy foods such as sodas and candies/sweets. Like everything else though, is not necessarily a health concern when a person consumes it in moderation.
Fructose is digested in the liver to produce mainly glucose (~50%), and minor amounts of glycogen (>17%), lactate (~25%) and a small amount fatty acids.
People with fructose intolerance cannot digest these sugars as normal and may experience bloating, abdominal pain, and diarrhea. Sound familiar? I see those symptoms on a daily basis in my private group. But they are symptoms of many conditions. Often, it’s difficult to sort out the symptoms and find the root cause. For some people, this may be one of the causes and trial and error is necessary to rule out.
Causes and types of fructose intolerance
The term “fructose intolerance” can be misleading as there are two types:
If you have dietary fructose intolerance, cells in your intestine don’t absorb fructose as they should. Looking at various studies on the internet, it appears fairly common. In people with dietary fructose intolerance, eating foods high in fructose can lead to uncomfortable symptoms, including:
Fructose intolerance is sometimes called fructose malabsorption.
This is a genetic condition in which people are born without an enzyme that breaks down fructose. Without this enzyme, they can’t digest fructose at all. Symptoms show up soon after babies start eating their first solid foods. These babies typically show signs including:
Genetic testing can confirm a diagnosis of hereditary fructose intolerance. I very much suspect that most people with a heredity version will have known for some years and already be taking action to reduce or totally eliminate fructose consumption.
Fructose malabsorption may result from inflammation or damage to the small intestine that prevents it from fully absorbing fructose, meaning fructose remains in the gastrointestinal tract.
However, there are a number of risk factors that might be contributing to the overall condition or severity of the condition. Most are related to the intestines but also include stress factors.
Unlike my similar article covering Lactose Intolerance, the evidence of linkages to dietary Fructose Intolerance is not as easy to find. I also discovered that the exact causes are not known and there are many overlaps with Irritable Bowel Syndrome (IBS) and Small Intestine Bacterial Overload (SIBO). It’s a conundrum.
Surgery to the small intestine. When you consider the risk factors above, e.g. “Fructose malabsorption may result from inflammation or damage to the small intestine that prevents it from fully absorbing fructose, meaning fructose remains in the gastrointestinal tract“, it follows that surgery on the small intestine may be involved in reducing tolerance causing the symptoms listed above. This is the same effect as per Lactose Intolerance.
Sorting out the Symptoms
Although fructose elimination diets can give clues, another clue can be made via a Hydrogen breath test. It is normal to test for both lactose and fructose individually as part of the same test scheduled event(s).
Hydrogen breath test. After you drink a liquid that contains high levels of lactose or fructose, your doctor measures the amount of hydrogen in your breath at regular intervals. Breathing out too much hydrogen indicates that you aren’t fully digesting and absorbing lactose or fructose.
Fructose or lactose breath hydrogen tests do not diagnose an illness or abnormality; malabsorption of lactose and/or fructose is a normal phenomenon. Whether symptoms are severe can depend on many factors (including whether there is an underlying gastrointestinal disorder or disease), so the breath test on its own may not find the real causal problem of the symptoms.
This is something to be discussed with your doctors and if you have one, your registered dietitian.
For people with dietary fructose intolerance, there is no one-size-fits-all solution. Fructose intolerance symptoms can sometimes overlap with other conditions, such as irritable bowel syndrome (IBS) and small intestine bacterial overgrowth (SIBO), there’s no single test we can do to be 100% sure.
Most sites I researched seemed to indicate a reduction is all that may be necessary to make adequate improvements. Limiting your intake of fructose can be difficult since it eliminates so many fruits and vegetables. As above, to make sure that you’re getting adequate nutrition, you can work with a dietician or specialist.
I am not a doctor or any form of medical professional, practitioner or counsellor. None of the information on my website, or linked to my website(s), or conveyed by me on any social media or presentation, should be interpreted as medical advice given or advised by me.
Neither should any post or comment made by a follower or member of my private group be assumed to be medical advice, even if that person is a healthcare professional. Some content may be generated by AI which can sometimes be misinterpreted. Please check any references attached.
Please also note that mention of a clinical service, trial/study or therapy does not constitute an endorsement of that service, trial/study or therapy by Ronny Allan, the information is provided for education and awareness purposes and/or related to Ronny Allan’s own patient experience. This element of the disclaimer includes any complementary medicine, non-prescription over the counter drugs and supplements such as vitamins and minerals.
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