When is Low Fiber Diet Recommended?

What is dietary fiber?

Dietary fiber is defined as the edible parts of plant foods that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the large intestine.

Dietary fiber has several health benefits such as

• Good for gut health
• Prebiotic effect
• Prevents constipation
• Contributes satiety
• Beneficial effect on blood glucose and lipid levels etc

But there are certain conditions in which low fiber diet is prescribed because high fiber diet aggravates the condition.

Conditions in which low fiber diets are prescribed

Crohn’s disease

Crohn’s disease is a gut ailment in which the intestinal lining is inflamed. It can affect people of any age and it usually starts in childhood or early adulthood. The incidence is increasing worldwide. It may arise because of genetic predisposition or because of influence of environmental conditions (1).

Associated symptoms (2)

• Diarrhoea
• Loss of weight
• Stomach pain and cramps
• Blood in the stools
• Fatigue

Crohn’s disease is a chronic inflammatory bowel disease (IBD). It may trouble a person constantly or relapse every few weeks or months. There is no cure for Crohn’s disease but has to be managed. When affected by diarrhoea low fiber diet is prescribed till it subsides (3). Inflammation of the intestine needs to be brought down. Any step should be taken on doctor’s suggestion.

Irritable bowel syndrome (IBS)

IBS is a common gastrointestinal disorder and occurring rate ranges between 5 % to 20 % depending on the region and also the parameters used for evaluation (4). IBS symptoms are abdominal pain and altered bowel habits.  The person affected with IBS may have diarrhoea or constipation or both.

Associated symptoms (5)

• Stomach cramps
• Bloating
• Diarrhoea
• Constipation

It is not known what is the exact reason for the for a person to be afflicted with IBS. It is a result of the food passing too quickly or too slowly through the gut or because of sensitive gut or stress or family history. It affects the quality of life and there is no cure for this condition. Therefore, it has to be managed by using medicines and modifying diet. Low fiber diet is recommended when IBS is associated with diarrhoea (5). But low fiber diet is not recommended over a long period of time. Follow doctor’s instructions.

Ulcerative colitis

Ulcerative colitis is a long-term inflammatory disorder which affects the colon and rectum of the large intestine. It is often seen affecting young adults and more commonly seen in developed countries (6, 7).

Associated symptoms

• An urge to empty bowels frequently
• Diarrhoea sometimes with blood, mucus and pus
• Stomach pain

The severity of symptoms depends on seriousness of the condition that is inflammation of the colon.  There are periods when the symptoms flare up and sometimes there are no symptoms. When symptoms such as diarrhoea are to be managed a low fiber diet is prescribed.

Foods that are rich in dietary fiber

• Whole grains
• Bran rich foods
• Nuts
• Seeds such as flax seeds
• Vegetables especially green leafy vegetables
• Fruits

Low fiber diet is prescribed in some conditions where diarrhoea and inflammation of gut is seen. But this low fiber or low residue diet cannot be continued for long periods of time as it is not healthy. It is advisable to follow doctor’s suggestion.

References

1. Ha, F. and Khalil, H. (2015) Crohn’s disease: a clinical update, Therapeutic advances in gastroenterology. Vol. 8(6).https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4622286/
2. National Health Service (2018) Crohn’s disease. https://www.nhs.uk/conditions/crohns-disease/
3. Mayo clinic (2015). Lifestyle and Diet in Inflammatory Bowel Disease. https://newsnetwork.mayoclinic.org/discussion/lifestyle-and-diet-in-inflammatory-bowel-disease/
4. Moayyedi, P., Mearin, F., Azpiroz, F., Andresen, V., Barbara, G., Corsetti, M. and Tack, J. (2017) Irritable bowel syndrome diagnosis and management: A simplified algorithm for clinical practice, United European gastroenterology journal. Vol. 5(6).https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5625880/
5. National Health Service (2017). Irritable bowel syndrome (IBS)https://www.nhs.uk/conditions/irritable-bowel-syndrome-ibs/
6. Ford, A.C., Paul, M., Steven, B .H. and Joseph, B. K. (2013) Ulcerative colitis, BMJ. Vol.346.  https://www.bmj.com/content/346/bmj.f432
7. National Health Service (2019) Ulcerative colitis https://www.nhs.uk/conditions/ulcerative-colitis/