For those with Irritable Bowel Syndrome who alternate between diarrhea and constipation. Let's make good use of bidirectional dietary fiber, which is versatile in a sense.
Irritable Bowel Syndrome (IBS) has both constipation-predominant and diarrhea-predominant types, but the most troublesome is likely the type that 'alternates between constipation and diarrhea.' This is the most common type of IBS among Japanese people.
This creates a dilemma in clinical practice: should I prescribe a laxative or an anti-diarrheal?
Thinking you were constipated until recently, only to have diarrhea starting today... this unstable intestinal condition is directly linked to the 'concentration' and 'performance' of business professionals in their 30s and 40s.
I would like to suggest to such people how to use 'dietary fiber'.
What exactly is dietary fiber? Why is it necessary?
The busier you are, the more likely you are to:
Skip breakfast, eat out, or rely on convenience store meals
Consume plenty of coffee and alcohol but little water
Tend toward diarrhea due to stress, or constipation due to travel or meetings
This leads to a 'lifestyle that is harsh on the gut.'
You often hear on the internet or from health YouTubers that you should 'eat dietary fiber.' This is to incorporate the wonderful effects that dietary fiber has.
Dietary fiber generally has roles such as:
Regulating the 'volume' and 'movement' of stool
Serving as food for gut bacteria to cultivate the intestinal environment
Smoothing out sudden fluctuations in blood sugar and cholesterol
These roles help build the 'foundation' for your daily condition.
The point is to roughly grasp thatdifferent types have different areas of expertise.
Soluble and insoluble. It's enough to understand at least this much for now.
Insoluble dietary fiber has the following characteristics:
Does not dissolve in water
Absorbs water to swell and increase stool bulk
Physically stimulates the intestinal wall to promote peristalsis
Foods that mainly contain it are,
Brown rice and whole wheat bread
Legumes
Mushrooms, burdock root, and root vegetables
and so on. These are the first things that increase when you decide to 'eat more vegetable salads' or 'switch to brown rice.'
While they strengthen the 'pushing force' for those prone to constipation, taking too much can worsen gas, bloating, and abdominal pain, and can actually be counterproductive for those with diarrhea-predominant or mixed-type IBS.
What is water-soluble dietary fiber?
Dissolves in water to become a thick, gel-like substance
Retains moisture in stool, adjusting it to be 'neither too hard nor too loose'
Serves as food for gut bacteria (prebiotics), producing short-chain fatty acids that contribute to intestinal mucosal barriers, inflammation, and hypersensitivity
These are some of its characteristics.
The main foods and ingredients that contain this are:
Oatmeal and barley
Seaweed such as kelp and wakame
Fruits such as apples and citrus
Supplement ingredients such as psyllium (plantain seed husk), PHGG (partially hydrolyzed guar gum), and indigestible dextrin
and so on. Among these, there is a versatile, bidirectional type of dietary fiber!
Is there a special dietary fiber that can bring both diarrhea and constipation toward a healthy middle ground?
Among the water-soluble dietary fibers introduced,
'Psyllium' and 'PHGG (partially hydrolyzed guar gum)'
are not just ordinary dietary fibers; because they are excellent in both their physical properties and their effects on gut bacteria, they are in a 'special category that is effective for both constipation and diarrhea.'
Why are they 'special' water-soluble dietary fibers?
Psyllium (plantain seed husk) and PHGG (partially hydrolyzed guar gum) are both classified as water-soluble dietary fiber, but they possess several characteristics that make them superior to others.
Strong water retention and gel-forming ability
Psyllium expands significantly into a jelly-like state when it absorbs water, and PHGG also dissolves in water to become viscous, which helps retain moisture in the stool and makes it easier to create 'formed stool'.Regulating the gut microbiota as a prebiotic
PHGG, in particular, is highly fermentable; it has been reported to increase beneficial bacteria such as bifidobacteria and butyrate-producing bacteria, promote the production of short-chain fatty acids, and contribute to the maintenance of intestinal barrier function.Relatively low gas and bloating (especially with PHGG)
Compared to other prebiotics (such as inulin), it is applied in enteral nutrition and medical diets as a 'water-soluble fiber that is less likely to cause gas and is easy to use in clinical practice'.
This dual action of 'physically holding water while nurturing the gut environment' is a great strength for IBS.
Characteristics of psyllium. It expands significantly in the gut, adding moisture to the stool and stimulating the intestines.
Psyllium absorbs a large amount of water in the gut and expands, increasing the bulk of the stool, which stretches the intestinal wall from the inside and promotes peristalsis, or bowel movement.
It also turns into a gel to maintain moisture, making the stool as a whole softer and smoother.
As a result, in cases of constipation, the increased stool volume enhances the 'urge to evacuate,' and hard, pebble-like stool moves closer to a 'banana or sausage shape'.
That alone is amazing, but it also has beneficial effects on diarrhea.
The psyllium that has gelled in the gut forms a stool mass while holding onto excess water within the intestinal tract.
In other words, by absorbing excess water in the gut and binding loose stool together, it leads to comfortable, banana-shaped stools.
Characteristics of PHGG. It casts a strengthening spell on gut bacteria.
PHGG has effects similar to psyllium, but its areas of expertise are slightly different.
PHGG does not expand as dramatically as psyllium, but it shares the effect of retaining moisture and giving stool appropriate softness, volume, and cohesion. As a result, one can expect improvement from frequent, watery stools to less frequent, somewhat firmer stools.
Furthermore, a characteristic feature of PHGG is its excellent compatibility with gut bacteria.
PHGG is easily fermented by gut bacteria, and an increase in bifidobacteria, butyrate-producing bacteria, and fecal short-chain fatty acids has been demonstrated.
In other words, it helps and increases the bacteria that perform beneficial work in the gut, and these increased bacteria repair the walls of the large intestine. As a result, it brings about effects such as maintaining intestinal mucosal barrier function and suppressing the invasion of pathogenic bacteria and endotoxins!
These have been shown in animal and human studies, and for diarrhea and loose stools accompanied by inflammation or increased permeability, the possibility that it works in a direction to 'regulate' the cause itself is suggested.works in a direction to 'regulate' the cause itselfpossibility is suggested.
Therefore, its usefulness is also expected in medical and nursing care settings, especially for chronic constipation (in the elderly, bedridden, or those with low activity) against a background of a deteriorated gut environment!
In cases like IBS where the 'gut is sensitive and diarrhea occurs with the slightest stimulation,' this direction of 'regulating the barrier and soothing sensitivity,' combined with the physical gel effect, is thought to contribute to symptom improvement.
Summary: Dietary fiber that 'works for both constipation and diarrhea.' How about incorporating it specifically in this way?
To summarize the bidirectionality of psyllium and PHGG simply...
Retains water
→ "Keeps" stool moisture at an appropriate level
→ Increases stool bulk + increases softness
→ Increases the urge to defecate
→ Promotes bowel movements + leads to formed stool
Serves as food for gut bacteria
→ Gut bacteria produce short-chain fatty acids
→ Intestinal walls become healthier!
→ Improves peristalsis and barrier function
→ Improves barrier function, reduces inflammation, and improves gut flora
→ Weakens hypersensitivity to stimuli
In other words, the combination of "the ability to create "well-formed stool" while retaining moisture" and "long-term effects on the gut environment and barrier function" is truly wonderful!
While I cannot recommend specific products here, please choose products made by well-known manufacturers that have been certified by third-party organizations!
How to take them varies from person to person, but how about starting with these general guidelines?
Psyllium
Start with 3–5g per day (a little less than a teaspoon). Dissolve in at least one full glass of water, taken in 1–2 doses, morning and evening. Gradually increase up to about 10g/day while monitoring for gas or bloating. Space out from medication by 30–60 minutes.PHGG (such as Sunfiber)
Take around 5g per day (about one stick packet) either in the morning or at night. Whether for constipation or diarrhea, monitor your condition and increase up to 10g/day (2 packets). It is easier to continue even when busy at work if you associate it with "your usual meal" by mixing it into water, tea, miso soup, or yogurt.
If you are suffering from Irritable Bowel Syndrome with alternating constipation and diarrhea, please consult with your primary physician and try incorporating these!
Gorilla is a psyllium fan. The only downside is that it doesn't taste very good...
Information regarding the upper limit of psyllium intake from the Japan Health and Nutrition Food Association, etc. (related materials from the Food Safety Commission of the Cabinet Office)
PDN (NPO PEG Doctors Network) "Bowel Control in the Elderly and Partially Hydrolyzed Guar Gum"
https://www.peg.or.jp/lecture/topics/01.htmlTaiyo Kagaku Medical Food Related Materials "Physiological Effects of Partially Hydrolyzed Guar Gum (PHGG) and Its Application to Medical Foods" PDF
https://www.taiyo-medi.com/cgi-bin/report_cms/public/photo/p0006-420-615528.pdfNestlé Health Science "PHGG-containing Enteral Nutrition" Related Materials (PHGG-containing nutritional supplements, gut and health)
Example:
https://www.nestlehealthscience.jp/sites/default/files/2019-12/A11045-07_isocal_SemiSolid_Support.pdf
https://www.eiyounet.nestlehealthscience.jp/sites/default/files/2022-09/12116-01.pdfJ-STAGE "Various Health Benefits of Partially Hydrolyzed Guar Gum," "Usefulness of Partially Hydrolyzed Guar Gum (PHGG) in Bowel Control," etc.
J-STAGE "Treatment of Chronic Constipation - How to Use Bulk Laxatives -"
https://www.jstage.jp/article/naika/108/1/108_29/_pdfPMDA "Polycarbophil Calcium" Interview Form/Package Insert
https://www.pmda.go.jp/drugs/2000/g000704/38ctdp_1-320.pdfBritish Society of Gastroenterology guidelines on the management of irritable bowel syndrome
ESPEN guidelines on enteral nutrition (mention of Grade A recommendation for PHGG-containing enteral nutrition)
Irritable Bowel Syndrome and Dietary Interventions (Review of IBS, dietary fiber, and prebiotics)
The Role of Diet in Functional Dyspepsia Management (The positioning of FD, diet, and dietary fiber)
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