Fructose Malabsorption

Introduction

Description

Symptoms

Diagnosis

Treatment

Download FREE printable brochure

References

Introduction

Most people (yes, most people) get more fructose than their digestive system can absorb. Most people cannot properly digest all the fructose they get every day from an apparently normal and healthy diet. If you are eating large quantities of fruit thinking it's healthy, well think again. A normal healthy adult can properly digest 25-50 grams of fructose per day. Many people have difficulty digesting less than that, and a few have difficulty with any fructose at all.

Here are a couple of examples of the fructose content in some common high-fructose foods:

Apple 35 grams per kilo
Asparagus 11 grams per kilo
Watermelon 23 grams per kilo
Can of soft drink (soda) 20-35 grams

If you have a high fructose diet, and your digestive system is able to absorb all that fructose, you'll suffer from weight gain / obesity. If your digestive system cannot absorb all the fructose, you'll suffer from the FM symptoms described below.

Description

Fructose malabsorption is a common digestive disorder in which absorption of fructose (or other sugars like lactose or sorbitol) in the small intestine is impaired. About 30-40% of people suffer from FM.

Fructose intolerance (as opposed to malabsorption) is a rare (1 in 10,000 people) and potentially fatal condition in which the liver enzymes that digest fructose are deficient. Fructose intolerance will not be further discussed in this article.

If you eat more fructose than your small intestine can absorb, the excess fructose passes through to the large intestine. In the large intestine, the fructose prevents the absorption of water. This causes watery stools / diarrhoea, and prevents absorption of minerals and vitamins. The abnormal sugar in the large intestine also feeds the bacteria and yeasts there, producing hydrogen, carbon dioxide and methane. These gases create pressure in the large intestine, causing bloating, abdominal pain and flatulence.

Symptoms

The symptoms of fructose malabsorption have some similarities to those of irritable bowel syndrome (IBS), food allergies, food intolerance, and the inability to digest properly (weak digestion). These symptoms can also be caused by yeast sensitivity or candida, from which around 1 in 3 people suffer. Interestingly, candida is one of the consequences of FM

Immediate symptoms (within minutes of consumption, and up to 3 days)

Flatulence
Bloating and distension (from fermentation in the small and large intestine)
Diarrhoea (or less commonly, constipation)
Indigestion / stomach pain / abdominal pain
Fatigue / lack of energy / tiredness
Brain fog / negative emotions
Nausea or even vomiting if large quantities of fructose are consumed

Long term symptoms

Sugar craving (or sometimes aversion)
Poor mineral and vitamin absorption causing anaemia, malnourishment and general poor health. Often B vitamins, folic acid, tryptophan, zinc, iron, magnesium, calcium and other vitamins and minerals will be low. Patients take supplements of these minerals and vitamins with little or no benefit, because they are not being absorbed. They eat good high-nutrient foods, but again many micronutrients in this food are not digested properly
Poor skin, nails and hair
Underweight, difficulty gaining weight (however, it is also possible to be overweight whilst suffering FM)
Being moody, early signs of mental depression (2)
Osteopenia / osteoporosis, which can also be caused by a diet high in fructose and low in magnesium (1)
Blood triglyceride levels raised
Heart disease (3)
Inflammation in many forms (skin problems such as rashes, hives, eczema, dermatitis etc, IBS, heart disease)

Diagnosis

Hydrogen breath test
Stool test
Self-diagnosis - keep a diary of all foods/drinks taken, and symptoms noticed. The journal is important, because the effects of some foods can take hours or even up to 3 days to start

Treatment

Doctors say there is no known cure for FM.

However, there is much anectdotal evidence that dietary changes can eliminate all symptoms, restore normal digestion, and maintain subsequent health and longevity. After you have been symptom-free for some months, you can gradually re-introduce small quantities of many of the foods that previously caused problems. It seems that being symptom-free for a long period allows fructose malabsorption to heal.

Foods to avoid, Foods to heal

I have produced a simple three page brochure detailing the foods to avoid if you suffer from fructose malabsorption. It also lists foods that are safe for FM.

Firstly, it lists foods that contain a high level of free fructose. Glucose helps the small colon to absorb fructose. So if a food is high in fructose, but also contains as much or more glucose, you can usually eat it with no ill-effects. It also lists the foods that are high in fructans that usually cause the same problems.

If this does not solve the problem within a few weeks, you may need to follow the stricter low FODMAP guidance detailed on the next two pages. FODMAPs are Fermentable Oligosaccharides (eg: fructans, galactans), Disaccharides (eg: lactose), Monosaccharides (eg: fructose) and Polyols (eg: sorbitol, mannitol, maltitol, Xylitol, isomalt etc). These food molecules may cause the same food absorption problems as fructose. The brochure lists those foods that are high in FODMAPs. It also lists those foods that have low or no FODMAPs.

FREE Download FODMAP/low fructose foods brochure

References

1. Milne D, Nielsen F. The interaction between dietary fructose and magnesium adversely affects macromineral homeostasis in men. Journal of the American College of Nutrition. 2000;19(1):31-37

2. Ledochowski M, Widner B, Bair H, Probst T, Fuchs D. Fructose and sorbitol-reduced diet improves mood and gastrointestinal disturbances in fructose malabsorbers. Scandinavian Journal of Gastroenterologist. 2000;10:1048-52

3. Busserolles J, Gueux E, Rock E, Mazur A, Rayssiguier Y. High fructose feeding of magnesium deficient rats is associated with increased plasma triglyceride concentration and increased oxidative stress.
Magnesium Research. 2003;16(1):7-12