Recently 3D Muscle Journey (3DMJ), specifically their dietitian Steve Taylor, put out a video about constipation: Strategies for Relieving Constipation. I would encourage everyone who reads this to also watch the video.

There were enough things said that I was skeptical about that I felt compelled to write the following initial comment on Instagram (IG);

“I was surprised by a number of your recommendations. My surprise comes from my current understanding that there is little to no quality evidence for them.”

Along with that response I included a number of quotes from a number of published papers to support my concerns. What ensued was a great discussion with Eric Helms, the Chief Science Officer of 3DMJ, which was all on IG if anyone wants to see all the back and forth

Before diving into the details, there are a few important points.

First, I want to highlight it is possible to have a civil, rational, productive discussion on IG. Clearly not common and still not the most useful method, but possible. 

Second, all of the lifestyle habits suggested in the video, which will be explored below, have little to no physical risk. Furthermore, even if they don’t help with constipation, doing these behaviors on a regular basis is likely to have many physical and mental benefits. From a health promotion perspective, I have no issues with what was said. What I am currently concerned about is the fact that nearly all of the recommendations have little to no quality evidence to support their effectiveness with constipation. 

Third, my goal here is to lay out what the evidence supports or does not support with respect to the ideas put forth in the video and do so in a clearer and more detailed fashion (a fair amount of the following was put forth during the IG discussion). I could be missing some important info or misunderstanding something, so feel free to give feedback.  


Constipation, according to the Mayo Clinic,

Signs and symptoms of chronic constipation include:

  • Passing fewer than three stools a week [some gastro experts state that even less frequent stools is not necessarily unhealthy, as long as it is a well formed stool and easy to pass (Tan & Seow-Chen 2007)] 
  • Having lumpy or hard stools
  • Straining to have bowel movements
  • Feeling as though there’s a blockage in your rectum that prevents bowel movements
  • Feeling as though you can’t completely empty the stool from your rectum
  • Needing help to empty your rectum, such as using your hands to press on your abdomen and using a finger to remove stool from your rectum

Constipation may be considered chronic if you’ve experienced two or more of these symptoms for the last three months.” (Mayo Clinic)

This is not about not having a bowel movement (BM) one day, or feeling more bloated or even having a BM that is a bit too hard and not easy to pass once in a while. There is certainly some crossover, but constipation is a specific diagnosis, as highlighted above, not unlike other specific digestive disorders such as Crohns or diverticulitis. 

The lifestyle factors discussed in the video are emotional/stress (how to potentially decrease the level of stress), diet (fluid, fiber, & meal frequency) and exercise. There was also a recommendation to create a consistent bathroom habit. These are not bizarre recommendations. In fact, these are common recommendations from a number of reputable sources, such as the NIH, specifically the National Institute of Diabetes and Digestive and Kidney Disease (NIDDK 2018), the American Gastroenterological Association (Bharucha et al 2013) and a popular nutrition textbook (Whitney & Rolfes, 2004). However, as you will see, there is often little to no quality evidence to support the recommendations. 


The video starts with addressing the emotional/stress aspect, so I will start with that one as well. The overall premise for considering stress is the potential of persistent high levels leading to negative perturbations to the HPA axis and autonomic nervous system (excessive sympathetic activity). This could lead to issues of altered gastric motility which could include constipation (Chang et al 2014). Furthermore, the prevalence of chronic constipation (CC) is frequent among those with psychological disorders, such as anxiety, depression, and anorexia (Aucoin et al 2014; Hosseinzadeh et al 2011; Forootan et al 2018; Levy et al 2006). Collectively, this evidence points to some mechanistic reasons why stress and emotions can play a role in CC. If high chronic stress as well as anxiety and depression are an issue, then improving this could potentially help with CC. This is all good for creating a hypothesis, but the real question is; are there studies that have found that interventions to improve these conditions help with CC?

The following are the two studies that Steven sent me as support for the stress aspect. A study published in 2001 tested a six week meditation intervention (Herbert Benson’s 1975 Relaxation Response Meditation program) on IBS (Keefer & Blanchard, 2001). There was a year follow-up paper as well (Keefer & Blanchard 2002). The sample size was very small, N=13 for the original study and N=10 for the one year follow up. In the original study they did look at constipation but the results did not find a statistically significant difference. In the year follow-up, there was no mention of constipation. I don’t see how these studies support the emotional/stress aspect of CC.

The next paper was originally put forth by Eric.

Aucoin, M., et al (2014). Mindfulness-based therapies in the treatment of functional gastrointestinal disorders: a meta-analysis. Evidence-based complementary and alternative medicine:

Only 7 studies met the inclusion criteria for the meta-analysis which was about 6 years ago, so there could be a few new ones since then. Based on the number of studies I think it’s fair to say there is currently a dearth of studies in this area. Furthermore, of the studies that have been done, there are significant concerns about the quality of the studies. The authors of the review state;

4.2.Quality. Quality Assessment Of The Studies Revealed Some strengths, but largely weaknesses and deficiencies. Overall, the current literature has not responded to challenges relating to increased quality in design, conduct, and reporting that may impact credibility in the field of mindfulness or other psychological interventions[26]. (p8)

It’s also important to highlight the fact that none of the studies included were specifically looking at constipation, they were virtually all about IBS, which can have a constipation aspect but not always.

“Although a statistically significant finding was demonstrated on pooled effect sizes, the low power, small number of studies, and overall high risk of bias in study design or completeness of reporting suggest that this should be interpreted with some discretion.” (p10).

Conclusion.Studies [7] suggest that mindfulness based interventions may provide benefit in functional gastrointestinal disorders; however,substantial improvements in methodological quality and reporting are needed.” (p10)

This paper does lend some support to the idea that stress/emotions and mindfulness-interventions could play a role in CC, however, the evidence is very weak.

Reviewing a number of papers on the etiology and potential treatment recommendations for CC, there is usually little to no mention of stress and mood or recommendations to improve these relating to this particular condition. If it is even covered, the authors usually have little to no quality evidence to support it. The following 4 papers (Paré et al. 2007; Bove, A., et al 2012; Forootan, M., et al. 2018; Black, C. J., & Ford, A. C. 2018) seems to be a good representation of typical recommendations regarding the etiology and treatment of constipation.

Paré, P., et al. (2007). Recommendations on chronic constipation (including constipation associated with irritable bowel syndrome) treatment. 

Interestingly, the oldest paper reviewed here, has, by far, the largest section on the psychological aspects related to the cause and potential treatment of CC.

  • “Hypnotherapy and cognitive behavioural therapy

Statement 35: Various forms of behavioural therapy, including hypnotherapy and cognitive behavioural therapy (CBT), are useful, safe therapies for selected people with IBS-C [irritable bowel syndrome with constipation]. (Level B; vote: a 70%, b 30%).” (p.14B)

The authors also state;

“Controlled trials of behavioural intervention for IBS-C are limited, but there is evidence to suggest that CBT and hypnotherapy may be helpful (217,220,223,224,226).” (p.15B)

“Psychological factors associated with IBS are not thought to be causal; rather, they influence gut function through the interaction of the central and enteric nervous systems (221).”

A few key points. First there are many studies referenced in the paper, but most are about IBS and not specifically about constipation. In fact the authors highlight this, stating “There are limited data regarding the efficacy of CBT for IBS-C [with constipation]” (p.14B) Second, the intervention studies have found some positive effects with CBT and hypnotherapy on a number of symptoms of IBS. This does help support the view that there is likely a psychological aspect to this condition. Third, there are only a handful of intervention studies. What I found interesting is there has been virtually no studies done in about 20 years and, as you can see, from the dates of the following studies, many of them are nearly 30 years old. That does not make them bad or irrelevant, but I would think there would be some more recent studies on CBT/hypnotherapy on IBS, and more specifically on constipation.  I will briefly review a couple of them here.

Ref 218 – Guthrie, E., et al. (1991). A controlled trial of psychological treatment for the irritable bowel syndrome. Gastroenterology, 100(2), 450–457. 

“At 3 months, the treatment group [treatment] showed significantly greater improvement than the controls on both gastroenterologists’ and patients’ ratings of diarrhea and abdominal pain, but constipation changed little.” (p.450, emphasis added).

Two important aspects. First, the participants (n=53 for treatment), were classified as non-responders to typical medical treatments at the time, making these the tough cases. Second, there were some psychological improvements from the intervention. But, when it came to constipation there was statistically no effect.

Ref 220 Drossman, Douglas A et al. (2003). Cognitive-behavioral therapy versus education and desipramine versus placebo for moderate to severe functional bowel disorders [FBD]. Gastroenterology, Volume 125, Issue 1, 19 – 31.

Early in the discussion section, the authors state;

Although prescribing antidepressants and psychological treatments for patients with moderate to severe FBD is intuitively evident, has been extensively reviewed,6, 7, 8 and is commonly practiced,1, 3, 9 to date no conclusive data from well-designed studies have emerged.” (p.20, emphasis added)

From what the authors highlighted, at the time of publication (2003), still no quality studies.

Some details of the study

N = 431

“402 of the 431 participants allocated to treatment (93.3% of randomized) actually entered into treatment and were included in the ITT analysis. Of these 402 participants, 308 completed all 12 weeks of treatment and another 13 completed 8–11 sessions, comprising 321 participants (74.5% of the 431 randomized) in the per-protocol analysis.” (p.23)

Gender = All females, with moderate to severe FBD.

Duration = 12 weeks

The intervention (N=215) was;

 “one-on-one hourly sessions from the same trained psychologist at each site with an intervention of either (1) 12 weekly hour-long sessions of CBT originally developed by Beck et al.19 and modified by Toner et al.20 that focused on modifying the influence of attention, personal appraisal, sex-related cognitive schemas, and illness attribution as related to the gastrointestinal symptoms as a means to develop more effective coping strategies or (2) 12 weekly modified-attentional control sessions (EDU) with the same therapist providing CBT, where each week the participants reviewed their symptom diaries, read educational materials mainly taken from a book on FBD,21 and then discussed the information with the therapist. (pp.20-21).


“Finally, the data suggest that the predicted outcomes relate primarily to subjective global assessments and quality of life more than to improvements in pain or bowel habit per se.” (p.30, emphasis added)

I think a fair assessment of this study would result in the conclusion that CBT can have some psychological benefits for women with FBD, but not necessarily improve constipation. Furthermore, the CBT and EDU interventions could be classified as intense (1 hour sessions, once a week, for 12 weeks).

Bove, A., et al (2012). Consensus statement AIGO/SICCR diagnosis and treatment of chronic constipation and obstructed defecation (part II: treatment).

  • Nothing about stress or emotions or strategies to improve these to improve constipation

Forootan, M., et al. (2018). Chronic constipation: A review of literature.

“Overall, a number of factors contribute to constipation including lower social economic status, lower parental education, physical activity, medications, depression, physical and sexual abuse, and everyday life events [4,13–15]” (p2)

Here are the studies they reference;

  • Ref 4- Wald A, Scarpignato C, Kamm MA, et al. The burden of constipation on quality of life: results of a multinational survey. Aliment Pharmacol Ther 2007;26:227–36.
  • Ref 13- Dukas L, Willett WC, Giovannucci EL. Association between physical activity, fiber intake, and other lifestyle variables and constipation in a study of women. Am J Gastroenterol 2003;98:1790–6.
  • Ref 14- Haug TT, Mykletun A, Dahl AA. Are anxiety and depression related to gastrointestinal symptoms in the general population? Scand J Gastroenterol 2002;37:294–8.
  • Ref 15- Lu CL, Chang FY, Chen CY, et al. Significance of Rome II-defined functional constipation in Taiwan and comparison with constipation-predominant irritable bowel syndrome. Aliment Pharmacol Ther 2006;24:429–38.

I am not seeing a single intervention study. This is all about the associations of mood/emotions and digestive issues/constipation.

“1.5 Diseases and conditions as secondary cause of constipation

Psychological conditions: depression, anxiety, eating disease.”

“1.8 Psychoaffective disorders

Patients with constipation often have psychological disorders in a variety of stressful life events such as anxiety, depression, physical and sexual abuse, and anorexia nervosa, as well as a concomitant eating disorder.[4,13–15,26–29] It has been indicated that patients with chronic constipation, especially those with dyssynergic defecation, had had an important psychological disorder.[30]

In contrast, a study has reported that there is no relationship between psychological distress and stool frequency in patients with slow transit constipation.[31] However, it is complicated to determine how constipation is influenced by these factors.”

In these sections (1.5 & 1.8) the authors reference 4, 13-15 (see previous section), as well as the following

  • Ref 26- Whitehead WE, Drinkwater D, Cheskin LJ, et al. Constipation in the elderly living at home. Definition, prevalence, and relationship to lifestyle and health status. J Am Geriatr Soc 1989;37:423–9.
  • Ref 27- Chun AB, Sokol MS, Kaye WH, et al. Colonic and anorectal function in constipated patients with anorexia nervosa. Am J Gastroenterol 1997;92:1879–83.
  • Ref 28- Hosseinzadeh ST, Poorsaadati S, Radkani B, et al. Psychological disorders in patients with chronic constipation. Gastroenterol Hepatol Bed Bench 2011;4:159–63.
  • Ref 29- Sonnenberg A, Koch TR. Epidemiology of constipation in the United States. Dis Colon Rectum 1989;32:1–8.
  • Ref 30- Rao SS, Seaton K, Miller MJ, et al. Psychological profiles and quality of life differ between patients with dyssynergia and those with slow transit constipation. J Psychosom Res 2007;63:441–9.
  • Ref 31- Devroede G, Girand G, Bouchoucha M, et al. Idiopathic constipation by colonic dysfunction: relationship with personality and anxiety. Dig Dis Sci 1989;34:1428–33.

Again, not a single intervention study. So of all the references for the psychological sections, there is not one intervention study.

“3. Overall approach for managing chronic constipation”

It’s interesting, although not surprising, based on the data presented, that under the section about what to do to manage CC, there are no recommendations for stress management or other psychological treatments. 

Black, C. J., & Ford, A. C. (2018). Chronic idiopathic constipation in adults: epidemiology, pathophysiology, diagnosis and clinical management.

  • Nothing about a direct connection between stress/emotions and constipation and therefore no recommendations to improve this to improve constipation

Finally, I find it interesting, and pertinent, that a relatively recent textbook (2007) on stress management (Lehrer et al, Principles and Practice of Stress Management, 3rd Ed) has nothing about constipation (constipation, functional constipation, chronic constipation), not a single page referenced in the extensive index. The only thing close is two pages about IBS. This  does not mean there is no connection. However, you would think a 712 page textbook on the subject of stress and health/disease would explore the connection between stress and constipation, to some degree, if there was some amount of evidence for it.

Overall, I would say there is very likely a psychological aspect to CC and other digestive issues. In fact, psychology is a huge part of lifestyle habits and is actually where my focus has been for over a decade now, so I definitely have a bias in favor of psych stuff. There is a challenge of determining causality, seems it’s likely bi-directional. Therefore having constipation could contribute to high levels of stress which would be a symptom rather than a cause. Also, the stress (or anxiety or depression) could then exacerbate the condition. Furthermore, the studied treatments (CBT, MBSR, etc), typically require a significant amount of time/effort, meaning it might take more than just trying to relax while on the toilet. Although, that could help and I can’t see how it would make it worse, but it’s likely going to take a lot more than that to help. Overall, improving how we think and how we handle emotions (ie, CBT, ACT, Motivational Interviewing, etc) is very likely a good thing and, like being active and eating healthy, little to no risk. At this time, the evidence is weak that it directly improves constipation. Which is why I was very skeptical when Steve said “It’s [emotions/stress] extremely important” (0:23) and “We know it [stress/emotions] has a huge impact” (2:12).



There is little doubt, due to a lot of research, that exercise can have many physical and psychological benefits. What seems less clear, does exercise help with constipation? Looking at the same 4 papers (Paré et al. 2007; Bove, A., et al 2012; Forootan, M., et al. 2018; Black, C. J., & Ford, A. C. 2018) as above, the answer would be no. But maybe there is some benefit? Let’s take a look.

From Pare et al 2007

“Statement 13: There is insufficient evidence to recommend exercise to improve CC. (Level D; vote: a 80%, b 20%).” (p.9B)

From Bove et al 2012

Trials evaluating the effect of exercise in constipated patients are lacking. Increased physical activity is often recommended for patients with chronic constipation, but there is no evidence that constipation can be improved by increased physical activity.” (p.4995, emphasis added)

From Forootan, M., et al. 2018

“3. Overall approach for managing chronic constipation” (p.6)

Nothing about exercise

From Black, C. J., & Ford, A. C. 2018

“In CIC specifically, although intervention programs to increase physical activity may be of some help in elderly patients (62), there is no evidence to suggest that increasing levels of physical activity in younger people is beneficial (23).” (p.10)

The following is a paper Steve sent me during the IG discussion regarding exercise.

Iovino, P., et al. (2013). New onset of constipation during long-term physical inactivity: a proof-of-concept study on the immobility-induced bowel changes. PloS one, 8(8), e72608. 

This was an interesting study, but it seems only tangentially relevant (largely irrelevant to the circumstances most people dealing with constipation have) to most people as this was about what would happen with complete bed rest for 35 days. 

“all subjects were kept strictly lying in bed for a period of 35 days, even to perform all daily activities, such as defecation”

This was also a small study with only 10 participants, only males, but it was well controlled.


“Our results showed a new onset of functional constipation at the end of 35-days of bed rest in 60% [6 of 10] of healthy volunteers as diagnosed by Rome III criteria.”

But, the authors also state;

“Stool consistency and bowel symptoms were not influenced by prolonged physical inactivity. In addition, no significant changes were observed in general health, in mood state and in quality of life at the end of bed rest”

My takeaway from this study. Even complete bed rest only resulted in mild functional constipation in 6 out of 10 people. Conversely, it seems even complete bed rest does not automatically lead to constipation as 4 of the 10 participants did not have an issue. There is likely a threshold of movement/activity that plays a role in helping the digestive tract work well. At this time, that threshold is not clear. It could be the amount most people get from activities of daily living (ADLs). Maybe it’s more, but this study does not elucidate that aspect.

One final, and recent, paper on the topic. This one does show some positive effects from exercise.

Tantawy, S. A., et al (2017). Effects of a proposed physical activity and diet control to manage constipation in middle-aged obese women. Diabetes, metabolic syndrome and obesity : targets and therapy, 10, 513–519. 

There are many aspects that make this study particularly relevant, which is age, gender, type and duration of exercise. Here are the details;

“This study included 125 obese women (age 20–40 years) who had chronic constipation. Participants were randomly assigned to two groups. Group A included 62 women who received a suggested protocol of physical activity, a low-calorie diet, and the routine standard care for constipation, whereas Group B included 63 women who received only the standard medical care for constipation and a low-calorie diet. Both groups followed the program for 12 weeks.” (p.513).

“Each woman in Group A participated in the exercise training program for 12 weeks, 3 times per week, with each exercise session lasting 60 minutes”

“The exercise session was started by a 10-minute warmup, which involved walking without any resistance or inclination on the walkway of the treadmill, followed by 40 minutes of walking with 15 degrees of inclination and a speed adjusted to reach 20%–40% of the target heart rate (THR) in the first 6 weeks of the study; the speed was increased to reach 40%–60% THR in the next 6 weeks of the study. The session ended with 10 minutes of recovery period, in which the intensity of the exercise was reduced to the level of the warm-up.”


“The main findings of this study showed that all measurements were significantly improved at the end of the study period among patients in both groups, except for BMI, which decreased only among patients in Group A. As reported in Tables 2 and 3, the percentage of change of BMI in Group A was 11.3%, whereas it was 5.6% in Group B” (emphasis added)

“In this study, the BMI of women in Group A significantly reduced and showed significant correlation with both PAC-SYM scores and PAC-QOL scores”

“Last [limitation], the participants’ fluid intake was not covered in this study”

I think this study does lend some support for exercise helping constipation. However, due to the combination intervention (reduce calorie intake, weight loss, and exercise), and not closely monitoring fluid intake/hydration, it is harder to clearly know the benefit came from the exercise, but seems like a fair assumption that at least some of the change was from it. 

This study, along with Daley et al (2008), although a lower quality study, and Zamany et al (2013) certainly supports the potential benefit of moderate exercise (specifically walking) to help with constipation. However, the study by Meshkinpour et al (1998), which included a 4 week intervention of 1 hour of walking 5 days a week, which increased overall walking from an average of 1.8 miles to 3.24 miles, did not lead to any changes in constipation. I would say this was a moderate quality study. Collectively, there are a lot of unanswered questions with respect to type, frequency, duration, and intensity. What is the threshold to trigger the response? Should it be done around meals? Etc.

During my deeper dive into the research I have actually changed my position some since the IG discussion. I think there is enough evidence (mechanistic and interventions) to suggest that if someone has a very sedentary lifestyle, the addition of walking could help with constipation. Furthermore, from this evidence, the lack of a recommendation for exercise from the four papers (Paré et al. 2007; Bove, A., et al 2012; Forootan, M., et al. 2018; Black, C. J., & Ford, A. C. 2018) seems incorrect.



Steve stated “Let thirst and urine color be your guides”, which seems like good advice. But what didn’t seem clear was the distinction of hydration status and the effects of fluid on constipation. 

The hydration color index highlighted by Steven, does seem to be a quick and easy method to check for potential dehydration. He also rightly points out a couple of its limitations. The evidence does find that dehydration can contribute to constipation and therefore drinking more fluids can be helpful. However, if someone is not dehydrated, more fluids will not help with constipation 

So here are what the 4 papers (Paré et al. 2007; Bove, A., et al 2012; Forootan, M., et al. 2018; Black, C. J., & Ford, A. C. 2018) say about fluid/hydration.

From Pare et al 2007

Statement 11: There is insufficient evidence to support the use of additional fluid intake to improve CC. (Level D; vote: a 80%, b 20%).” (p.X)

From Bove et al 2012

“Trials evaluating the effect of increased liquid intake in constipated patients are lacking, and there is no evidence that constipation can be improved by increasing oral fluid intake, unless the patient is dehydrated” (p.4995).

From Forootan, M., et al. 2018

Interesting under the section “3. Overall approach for managing chronic Constipation” section there is no mention of fluid intake. However, under the section “1.3. Causes of constipation”, the authors state; “and low consumption of fluids can lead to constipation.” (p.2)

From Black, C. J., & Ford, A. C. 2018

“There is no evidence that CIC can be successfully treated by increasing fluid intake, unless there is evidence of dehydration”

What the evidence seems to be clear on, if dehydrated, which may be noticed by the color of urine, ingesting more fluids (which would vary depending on the severity of dehydration) could help with constipation. Otherwise, drinking more fluids seems unlikely to help.

As previously mentioned, Steve did mention the urine color index chart, which does seem like a useful tool with good evidence to support it  (Armstrong et al 1998; Perrier et al 2016). Here is the chart (which is the one that Steven used as well). It seems a 1 to 3 is ideal, 4 to 6 is mild dehydration and 7 or 8 is severe dehydration.


Meal Frequency

Does eating more frequently help? Steve states “Instead of 1-2 meals, have many smaller meals instead” (3:32) and “I have seen this be very effective” (3:56). He highlights the gastrocolic response as the reason based on the Malone et al reference. He quotes Malone et al;

The gastrocolic reflex is most active during morning time and immediately after meals. Using this physiological reflex to our advantage helps treat constipation. For both children and geriatric patients with constipation, using the toilet immediately after having breakfast and establishing a daily routine helps to improve constipation.” (emphasis added).

Okay, a number of things to digest here (pun intended). There is no dispute that the Gastrocolic response and resulting peristalsis occurs which seems mostly affected by eating but it also seems to be stimulated by certain aspects of the nervous system and circadian rhythms (Hansen 2003; Codoñer-Franch, P., & Gombert, M. 2018). It seems worth speculating, based on chrononutrition research so far, that meal timing could also play a role and is as plausible as the frequency aspect (Chaix, A. et al 2019).  Onto the more important points. It seems pertinent to point out that the recommendation is for “children and geriatric patients with constipation”. Therefore, this may not be applicable for those 18 to 65 (depending on the official cut off ages). Furthermore, of the 19 references in Malone et al 2019, there seems to only be two related to this statement, which are;

(1) Ref 4 – Deiteren A, Camilleri M, Burton D, McKinzie S, Rao A, Zinsmeister AR. Effect of meal ingestion on ileocolonic and colonic transit in health and irritable bowel syndrome. Dig. Dis. Sci. 2010 Feb;55(2):384-91.

  • “122 patients with IBS and 41 healthy volunteers”
  • “Total of 163 participants, 160 were female and 3 were male”
  • Average age was about 37 y/o
  • 3 prepared meals, breakfast, lunch and dinner, were fed to the participants, approximately 4 hours apart

“After feeding, ICT [Ileocolonic transit] is increased in IBS-D, whereas colonic transit is blunted in IBS-C.” (p.384, emphasis added).

“The blunted colonic response to food in IBS-C patients 2 hours postprandially in our study is consistent with the overall results of Bouchoucha et al. and with other reports of impaired colonic response to food in constipated patients (4145).” (p.388)

(2) Ref 16 – Bassotti G, Betti C, Imbimbo BP, Pelli MA, Morelli A. Colonic motor response to eating: a manometric investigation in proximal and distal portions of the viscus in man. Am. J. Gastroenterol. 1989 Feb;84(2):118-22.

  • “Twenty-nine healthy volunteers of both sexes, 22-36 yr old, participated in the study”
  • “No subject complained of abdominal pain, distension, or bowel irregularities, and none had had previous abdominal surgery”
  • “After 30 min of basal adaptation, recording sessions were begun. Intraluminal activity was recorded for 2 h during fasting; then a 1000-kcal standard mixed meal was served. This meal has been previously shown to stimulate colonic motility (7, 9, 11, 14, 15); it consisted of a white bread (46-g) sandwich, with roast beef (132 g) and mayonnaise (22 g), and a milkshake (150 g) with vanilla ice cream (132 g). All the subjects ate the meal in 7-15 min. Thereafter, the recording session was continued for 3 h so that we might determine the prolonged effects of the test meal on colonic motility”

After reviewing these two references used by Malone et al,  I honestly don’t know how the authors came to their conclusion. Neither study was done on children or geriatric patients. It also did not show that it helped with constipation. I don’t see any good evidence that supports their conclusion.

The 4 main papers referenced throughout make no mention of meal frequency (Paré et al. 2007; Bove, A., et al 2012; Forootan, M., et al. 2018; Black, C. J., & Ford, A. C. 2018). Furthermore,  the NIH, specifically the National Institute of Diabetes and Digestive and Kidney Disease (NIDDK 2018), the American Gastroenterological Association (Bharucha et al 2013) and a popular nutrition textbook (Whitney & Rolfes, 2004) do not mention meal frequency. Additionally, it is my current understanding there is not a single intervention study that has tested varying meal frequencies to see if it has a positive or negative effect on constipation. So how many meals will do the trick? Two, four, or many eight? Also, how much would need to be eaten at the meal? Is there a certain volume or macronutrient amount that is needed to stimulate the gastrocolic reflex? This does seem likely as Deiteren et al highlight The caloric content and meal composition may be important determinants of the magnitude of colonic response to food” (p.388). At this time there seems to be many more questions than answers.

Collectively, like many of the recommendations, there is no solid evidence for an increase in meal frequency to help with constipation. However, it seems very unlikely to be any physical harm from increasing meal frequency, so it seems worth trying.


The final dietary aspect, fiber, will likely be the most contentious aspect. I would be willing to bet a large sum of money that the first thing most people think of when it comes to constipation is “I need to eat more fiber”. This is not surprising as this recommendation is everywhere. The 4 main papers used here all recommend it (will get to the specifics in a moment). The NIH, specifically the National Institute of Diabetes and Digestive and Kidney Disease (NIDDK 2018), the American Gastroenterological Association (Bharucha et al 2013) and a popular nutrition textbook (Whitney & Rolfes, 2004) also all recommend it. Steve also recommended it, stating “consume plenty of fiber, but not too much” (13:28) and he highlights the typical recommendations of “38 grams for most men, 25grams/day for most women or 14 grams per 1,000 calories” (13:28) as well as the recommendation to slowing increase intake to minimize negative effects. Certainly nothing shocking and no need to call the nutrition police. But, like other recommendations, does the evidence really support it?

Will start with what the 4 papers (Paré et al. 2007; Bove, A., et al 2012; Forootan, M., et al. 2018; Black, C. J., & Ford, A. C. 2018), referenced throughout, say about fiber.

From Paré et al. 2007

“Statement 12: Dietary fibre increases stool weight and shortens gut transit time. (Level D; vote: a 60%, b 40%).

The diets of patients with CC compared with control subjects do not differ in the amount of fibre in their diets (89). Fibre does increase stool weight and shortens gut transit time (98) but does not improve symptoms, either pain or stool frequency (99). One study (100) that followed patients with IBS for six months did find that fibre improved the symptoms of CC (hard stools and urgency) but only if the patients ingested 30 g of fibre or more daily. Abdominal distension, flatulence and diarrhea did not respond to the increased fibre diet (100). A recent review (101) concluded that fibre improves symptoms in CC but studies to date do not clearly identify a particular source of fibre that works best for constipated Patients” (p.9B)

From Bove, A., et al 2012

As part of the abstract/introduction, they state;

“Patients with normal-transit constipation should increase their fibre intake through their diet or with commercial fibre.” (p.4994)

“Current guidelines recommend the use of fibre in both dietary and supplement form for the first-line treatment of chronic constipation[17], but a recent review showed that there is little evidence to support this approach[18].” (p.4996)

They do highlight that soluble fiber, specifically a psyllium supplement could be helpful, concluding;

“The use of psyllium is supported by Level Ⅱ evidence, Grade B recommendation.” (p.4996)

From Forootan, M., et al. 2018

“Studies have indicated that a high-fiber diet can increase stool weight, resulting in a decreased colon transit time, while poor fiber diet induces constipation.[16] Moreover, it has been revealed that increased fiber diet could improve symptoms in patients with normal colonic transit and anorectal function, while constipated patients with delayed colonic transit patients have not improved by increasing dietary fiber.[17] Increasing fiber consumption does not make colonic transit normal, and may even worsen their symptoms through the fiber’s metabolism as a result of the gas produced.[18]” (p.2-3)

“Fiber intake has been demonstrated to improve functional constipation. It has been indicated that diets with soluble fiber (psyllium 15g daily or ispaghula) may benefit patients suffered from chronic constipation and IBS.[3] There have been studies that indicated less effectiveness of supplementation in patients suffered from slow defecatory disorders or slow- transit constipation (STC), whereas patients tend not to respond to fiber intake.[17] On the other hand, several studies reported that fiber supplements could improve bowel symptoms in patients with chronic constipation.[3]” (p.6)

Of the four papers, this one seems to present fiber in the most positive manner, although they do highlight that it will not help many and could make it worse for some. But, because of the overall positive position, I thought I would look at what evidence they used to support their position. As you can see from the quotes above, the following are the references they used along with some commentary.

[3] Suares NC, Ford AC. Systematic review: the effects of fibre in the management of chronic idiopathic constipation. Aliment Pharmacol Ther 2011;33:895–901.

This is actually a review of fiber supplements and not eating high fiber foods. This paper was highlighted by the Black & Ford (2018) paper as well and interestingly, one of the authors, Ford, was also one of the authors this paper. It did show some potential benefits from soluble fiber supplements, but the concern was the quality of studies were low.

[16] Tucker DM, Sandstead HH, Logan GMJr, et al. Dietary fibre and personality factors as determinants of stool output. Gastroenterology 1981;81:879–83.

“The present report includes data from 21 men. The ages of the men ranged from 18 to 50 adn average age of 24” (p.880) 

All the men were considered healthy and did not have an issue with chronic constipation.

This was actually a pretty interesting study, as it was 6 months in a  metabolic ward, so very well controlled.

The dietary aspect was very well controlled. All participants eat the same diet, but the intervention was a change of overall intake of fiber from 8-12grams to 26 grams/day. The increase in fiber came from a high fiber bread, which varied the source of added fiber (wheat bran, corn bran, soybean hulls, dehydrated carrot powder, and dehydrated apple powder) each month. 

This study did not specifically test if the increase in fiber reduces the incidence of constipation or if it relieves constipation. It was about the effects of changes/types of fiber and stool output which it did find an increase in output from higher fiber intakes. This is not surprising as there seems to be plenty of evidence that more fiber leads to more stool output. The real question, with respect to the current focus; does more fiber actually prevent constipation and would more help remedy constipation? Neither of those questions can be answered from this study. Overall this study is probably more supportive of a psychological aspect of constipation than fiber.

What seems particularly perplexing is how Fooratan et al used this to say there have been “studies”, when this was a single study.

[17] Voderholzer WA, Schatke W, Muhldorfer BE, et al. Clinical response to dietary fibre treatment of chronic constipation. Am J Gastroenterol 1997;92:95–8.

“One hundred, forty-nine patients [n=149] with chronic constipation (age 53 yr, range 18-81 yr, 84% women) at two gastroenterology departments in Munich, Germany, were treated with Plantago ovata seeds, 15-30 g/day, for a period of at least 6 wk. Repeated symptom evaluation, oroanal transit time measurement (radiopaque markers), and functional rectoanal evaluation (proctoscopy, manometry, defecography) were performed. Patients were classified on the basis of the result of dietary fiber treatment: no effect, n = 84; improved, n = 33; and symptom free, n = 32.” (emphasis added)

This study used Plantago ovata seeds, which is commonly referred to as psyllium husk, and is a fiber supplement and not a whole food. Therefore the increase was not from an increase from an increase in fiber rich foods (i.e., legumes, veggies, etc).

The authors list 2 studies, one from 1981 and one from 1997, neither which used an intervention of increasing fiber from whole foods. However, one used a higher fiber bread from a variety of added fiber concentrates, so this is close to a food. But, it seems suspect that a review paper done in 2018 is supporting their fiber recommendation from these two studies.

[18] Basilisco G, Coletta M. Chronic constipation: a critical review. Dig Liver Dis 2013;45:886–93.

This paper would fall into the same category as the four papers used throughout this paper and seems to cover similar material and have similar recommendations. Here are a couple relevant quotes.

A fibre-rich diet accelerates transit time, softens stool and increases stool weight, but a diet that is poor in fibre can induce constipation [26]. However, the consumption of dietary fibre is no different between constipated and non-constipated subjects [27]. Increasing dietary fibre improves symptoms in patients with normal colonic transit and anorectal function, but not in constipated patients with delayed colonic transit and defecation disorders [28], [29]. The latter are characterised by low stool weight and prolonged transit times regardless of the amount of fibre in their diet [26], which suggests that increasing their fibre intake does not normalise colonic transit and can even worsen their symptoms as a result of the gas produced by fibre metabolism.” (p.887, emphasis added).

Fibre supplements are traditionally considered the first-line treatment, although deficient fibre intake in patients with chronic constipation has not been demonstrated at referral centres [27], and there is little evidence that insoluble fibres are beneficial [84]…Taken together, these observations suggest that, rather than fibre supplementation, osmotic and stimulant laxatives should be considered for the first-line treatment of patients with chronic constipation seen at referral centres.” (p.888-890, emphasis added).

Again, this reference (18) by Footan et al seems like rather weak evidence.

From Black, C. J., & Ford, A. C. 2018

“Patients with CIC are often told to increase their dietary fibre intake, with guidelines suggesting 25g-30g of fibre per day. This should be introduced slowly, with gradual titration to avoid side effects.” (p.9)

They then conclude;

“Overall, the quality of evidence was low, and the findings should be interpreted cautiously, due to a high risk of bias among all included studies. Both these systematic reviews identified a need for further large studies of fibre for the treatment of CIC.” (p.9)

There are also two review papers that are frequently reference to support the use of fiber to help with constipation which are;

Suares, N. C., & Ford, A. C. (2011). Systematic review: the effects of fibre in the management of chronic idiopathic constipation. Alimentary pharmacology & therapeutics, 33(8), 895–901. 

Christodoulides et al (2016). Systematic review with meta-analysis: effect of fibre supplementation on chronic idiopathic constipation in adults. Aliment Pharmacol Ther; 44: 103–116

Three important aspects of these reviews. First, both were reviews about the effects of fiber supplements and not from a change of fiber intake from food. Second, the conclusions found weak to moderate positive effects. Third, the quality of studies were low. Collectively, they do lend some support for fiber supplements, but it does not lend direct support for higher fiber diets from food. 

From the four papers, as well as the two review papers, I think a fair conclusion is getting around 15-30 grams of fiber, particularly soluble fiber and likely from a fiber supplement, could help some people with constipation. However, for many people increasing fiber will not help and could exacerbate symptoms. The overall evidence is rather weak and mostly comes from low quality studies. There seems to be more to the story as there are a number of other papers on the topic that come to a far less positive view of fiber and constipation.

The first paper is likely the least controversial paper, which highlights the fact that low fiber (low residue) diets can be useful diagnostically as well as therapeutically for certain GI conditions.

 Vanhauwaert, E., Matthys, C., Verdonck, L., & De Preter, V. (2015). Low-residue and low-fiber diets in gastrointestinal disease management. Advances in Nutrition, 6(6), 820–827. 

“In most studies, information on the quantity of residue in the diet refers to the amount of fiber. Fiber is the part of fruit, vegetables, and grains that is not digested by the body and is proposed as a necessary component of a healthy diet and required for normal bowel movements (4). In practice, within human disease research, both the terms “low residue” and “low fiber” are used interchangeably. narrative review, we critically review the diagnostic and therapeutic values of low-residue and low-fiber diets in gastrointestinal disease management.”

“Currently, a number of human studies, still preliminary, are investigating the influence of low-fiber intake on the symptom signature of several gastrointestinal disorders.”

“Asymptomatic diverticulosis is commonly attributed to constipation caused by a low-fiber diet, although evidence for this mechanism is limited. Peery et al. (42) examined the associations between constipation and low dietary fiber intake with the risk of asymptomatic diverticulosis in 539 patients. Participants underwent colonoscopy and assessment of diet, physical activity, and bowel habits. The results of this study indicated that neither constipation nor a low-fiber diet was associated with an increased risk of diverticulosis.”

“Therapeutically, a low fiber diet [<10 grams] is part of the treatment in acute relapses of IBS,inflammatory bowel diseases, or diverticulitis. Upon achieving remission, the amount of fiber should be systematically increased until achieving the recommended amount of fiber in a healthy diet.”

This relatively recent narrative review does lend some support that a low fiber diet is likely not inherently bad and could be helpful for a number of digestive disorders, including constipation.

Müller-Lissner, S. A., Kamm, M. A., Scarpignato, C., & Wald, A. (2005). Myths and misconceptions about chronic constipation. The American journal of gastroenterology, 100(1), 232–242.

“As with any widespread disorder that has been incompletely understood, there are many strongly held beliefs, which are not evidence based and have arisen by observations and studies that were not rigorously performed. These beliefs, which are passed down from one generation to the next in oracular fashion, illustrate that certitude is not always the same as correctness.” (p232)

“In conclusion, a diet poor in fiber should not be assumed to be the cause of chronic constipation in general but may be a contributory factor in a subgroup. Some patients may be helped by a fiber-rich diet but many patients with more severe constipation get worse symptoms when increasing dietary fiber intake” (p.235)

Eswaran, S., Muir, J., & Chey, W. D. (2013). Fiber and functional gastrointestinal disorders. The American journal of gastroenterology, 108(5), 718–727.

“Despite years of advising patients to alter their dietary and supplementary fiber intake, the evidence surrounding the use of fiber for functional bowel disease is limited.”

“When fiber is recommended for functional bowel disease, use of a soluble supplement such as ispaghula/psyllium is best supported by the available evidence. Even when used judiciously, fiber can exacerbate abdominal distension, flatulence, constipation, and diarrhea.”

Tan, K. Y., & Seow-Choen, F. (2007). Fiber and colorectal diseases: separating fact from fiction. World journal of gastroenterology, 13(31), 4161–4167.

“One common but erroneous belief is that the moisture content of stool is increased when fiber intake is increased. The moisture content actually remains at 70% to 75% and does not change when more fiber is consumed. For most fiber substances, increase in quantity does not result in a more effective holding of water in the gut lumen[3,6].”

“The first question that needs to be asked must be whether one stool movement per day is the desired frequency for everyone? There is no evidence to support the theory that a long but normal residence of stools in the colon will lead to physical diseases[35]. Secondly, if an individual has a single bowel movement in a week but is able to evacuate all the faecal material easily, does this constitute a pathological bowel habit?”

“In summary, there is little physiological basis for increasing fiber intake and thus bulkiness of the stool in constipating and defaecatory disorders.”


Whilst it is not the intention of the authors to totally discourage fiber in the diet and the use of fiber supplements, there does not seem to be much use for fiber in colorectal diseases. We, however, want to emphasize that what we have all been made to believe about fiber needs a second look. We often choose to believe a lie, as a lie repeated often enough by enough people becomes accepted as the truth. We urge clinicians to keep an open mind. While there are some benefits of a diet high in natural fiber, one must know the exact indications before recommending such a diet. Myths about fiber must be debunked and truth installed.” (emphasis added)

Ho, K. S., Tan, C. Y., Mohd Daud, M. A., & Seow-Choen, F. (2012). Stopping or reducing dietary fiber intake reduces constipation and its associated symptoms. World journal of gastroenterology, 18(33), 4593–4596.

“There were 16 males (25.6%) and 47 (74.4%) females, median age 47 years (range, 20-80 years) included in the study. At the commencement of the study, all patients were already on a high fiber diet or taking fiber supplements. After 2 wk of a no fiber diet, patients were asked to continue on as little fiber in the diet as they were able to follow if this were to give them relief from their symptoms.

“At 6 mo, 41 patients continued on a no fiber diet and 16 were on a reduced fiber diet. The remaining 6 patients continued on a high fiber diet for various reasons including being vegetarians or inability to stop consuming dietary fiber for religious or personal reasons.”

“At 6 mo follow-up, the interval between bowel movements decreased with the reduction in fiber intake (P < 0.001). Forty one patients who completely stopped fiber intake had their bowel frequency increased from one motion in 3.75 d (± 1.59 d) to one motion in 1.0 d (± 0.00 d) (P < 0.001). Of 16 patients who reduced their dietary fiber intake, 12 patients had daily bowel movement, 3 had one bowel movement every 2 to 3 d and one had a bowel movement every 4 to 6 d, giving one motion per 1.9 d (± 1.21 d) on a reduced fiber diet compared with 1 motion per 4.19 d (± 2.09 d) on a high fiber diet (P < 0.001). There was no change in the frequency of bowel movement for patients who continued with high dietary fiber intake, with one motion per 6.83 d (± 1.03 d) before and after consultation (P = 1.00).”

“There was also a difference between the groups in the proportion of patients with associated symptoms. For symptoms of bloating, all of those on a high fiber diet continued to be symptomatic, while only 31.3% in the reduced fiber group and none of the no fiber group had symptoms (0%, P < 0.001)”

“CONCLUSION: Idiopathic constipation and its associated symptoms can be effectively reduced by stopping or even lowering the intake of dietary fiber.”

The results of this study should lead us to reexamine popular beliefs in benefits of dietary fiber and more studies should be undertaken to confirm or repudiate these results.” (emphasis added)

A couple more related aspects before wrapping up this section.

What about the carnivore diet?

Will start with the one year (famous or infamous, depending on your current bias) all meat diet.

McClellan, W. & DuBois, E. (1930). XLV. PROLONGED MEAT DIETS WITH A STUDY OF KIDNEY FUNCTION AND KETOSIS. The Journal of Biological Chemistry; 87, 651-668. 

“Two normal men [Steffanson and Anderson] volunteered to live solely on meat for one year, which gave us an unusual opportunity of studying the effects of this diet.” (p.651)

“At our request he [Steffanson] began eating lean meat only, although he had previously noted, in the North, that very lean  meat sometimes produced digestive disturbances. On the 3rd day nausea and diarrhea developed. When fat meat was added to the diet, a full re- covery was made in 2 days. This disturbance was followed by a period of persistent constipation lasting 10 days.” (pp. 653-654)

“ Andersen entered the ward January 6, 1928, and started with a prelimin- ary period on a mixed diet. The meat diet began January 24. No in- testinal disturbances occurred. Intensive study on the effect of this regime continued for 90 days…” (p.654)

“Both the men were in good physical condition at the end of the observation [one year]. There were no subjective or objective evidences of any loss of physical or mental vigor. The teeth showed no deterioration and gingivitis had disappeared. There was, however, an increase in the deposit of tartar on teeth of V. S. Bowel elimination was undisturbed-V. S. required no extra catharsis and K. A. was regular throughout. The stools were smaller than usual, well formed, and had an inoffensive, slightly pungent odor. No flatus was noted.” (p.659)

Clearly a small sample, only 2 people. But it was a year long and it was well controlled.

Then there are the hundreds of people eating a carnivore diet that seem to have normal bowel function (possible, maybe even likely, issues during the transition, first 2-4 weeks) that are described here. This seems fair game as anecdotes were a common reference for Steve (more on anecdotes soon, but briefly I am not a big fan). There is certainly the potential of significant diarrhea, which was articulated in amusing and painful detail by Jordan Synatt during most of his 2 week carnivore diet (very good, go watch it). A similar experience was when Joe Rogan tried a carnivore diet for 8 weeks. He also had some issues with major (explosive) diarrhea for a couple of weeks, but then his bowel movements seemed to normalize for the remaining 6 weeks. One more notable experience is from Andrew Zaleskit during his one month self experiment with the diet which he details in his Outside Online article . He also had some issues with diarrhea. I think it is important to point out that major changes in diet, such as quickly and significantly increasing or decreasing fiber intake as well as fat intake, can frequently cause temporary GI issues. Therefore, the drastic change could be why there is such severe diarrhea at first. It is also interesting that the problem was diarrhea and not constipation. 

The fiber part was clearly long, but It seemed necessary as fiber is a staple recommendation for digestive health and “healthy” eating overall (Dahl et al 2015, Anderson et al 2009). The fiber hypothesis has an interesting history, and a major driver of the current positive view of fiber for overall health and specifically the health and function of the digestive tract started with Dr Burkitt and Dr Trowell’s 1960 book, Western Diseases: Their Emergence and Prevention (Coffin & Shaffer 2006; Whorton 2000). At this point a lot of the evidence to support fiber recommendations comes from epidemiological research. Intervention trials have mostly used fiber supplements, not food. The idea that a low fiber intake is a cause of constipation and a higher intake of fiber is a remedy of constipation is also a ubiquitous idea, from the lay public and professionals. However, from looking at the evidence, really looking at it, it seems this hypothesis is on shaky ground particularly when it comes to digestive health and more specifically constipation. 

It is pretty amazing that the human body can function well on a wide range of fiber intakes, from virtually none t0 100 # grams (Sonnenburg 2014) a day. Although this should probably not be shocking, as humans can also thrive on a wide range of macronutrients, particularly carbs and fats. My contention is not to say that humans shouldn’t eat fibrous foods (the carnivore crowd can hold their applaus), nor am I saying that people should eat 30 plus grams a day (I guess everyone else can hold their applause, particularly the vegans). I think the point here is fiber is not a cure all for constipation and its health halo status is likely overblown. Fiber is also not an evil substance and it’s likely that many people can eat  a lot of it, say 20-40 grams a day, and have no issues and have some benefits. But, I think it should be acknowledged that it’s possible that humans could be healthy on little to none of it and when it comes to constipation maybe we should be less enthusiastic about its benefits.

The final aspect related to diet/fiber and constipation is the microbiome.

Who can discuss fiber and pooping and not mention the microbiome? First, this is an interesting topic and it seems there has been a surge of research in this area the past 20 years. Second, it seems very likely that the microbiome is an important driver of health and disease. Third, it seems early life events (breastfeeding, etc) and antibiotic use likely play a major role (Blaser 2017). Fourth, what is also evident, there is still a lot more unknown than known about the microbiome and health and disease (McBurney et al 2019).  A few notable quotes from McBurney and colleagues (2019);

“At present. A mechanistic understanding of the host-microbiome relationship is lacking, and there is a need for more research” (p.1890)

“Because of high interindividual variability of the human microbiome, it will be extremely complicated and might even be impossible to identify and validate features of the human microbiome and normal ranges that can be used to predict human health and disease risk” (p.1890)

“It might therefore be impossible to determine microbiome features that are universally healthy; what constitutes a “healthy microbiome” for one person or human population might well be unhealthy in a different context.” (pp.1890-1891)

Certainly diet plays a role in influencing the microbiome, but at this time it seems unclear what dietary factors affect it, to what extent, and for how long. Which gets us to the fiber aspect. When diet is discussed with respect to the microbiome, fiber is often the nutrient highlighted (fat also seems common). It certainly makes sense, based on how fiber interacts with the colon, that it would have some positive effects. 

When it comes to constipation, what aspects of the microbiome seem important and does fiber likely play a major role in it? A recent paper, Ohkusa et al (2019) Gut Microbiota and Chronic Constipation: A Review and Update, gives us a good insight of what the current evidence is. Here a few pertinent quotes;

“These findings are inconsistent, and currently no consensus exists as to which gut microbiota are involved in FC [functional constipation]. Because the intestinal flora is changed by age (9). However, some reports are analyzed the intestinal flora of FC in adults and the other reports are analyzed in children. Therefore, it seems to be difficult to explain the association of intestinal flora and FC.”

“Therefore, probiotics, prebiotics, and synbiotics may be effective treatment options for constipation. Because there are many studies in a small number and the types of probiotics are different, it is difficult to evaluate the effect. Therefore, it will be necessary to conduct a number of studies on specific probiotics.

“Results from clinical studies on probiotics and FMT [fecal microbiota transplantation] suggest that constipation is caused by dysbiosis of the microbiota”

“Conclusions: Evidence indicates that dysbiosis of gut microbiota may contribute to functional constipation and constipation-type irritable bowel syndrome. Targeting treatments for the dysbiosis of constipation by probiotics, prebiotics, synbiotics, antibiotics, and FMT may be a new option, especially for refractory constipation to conventional therapies.”

From this information, it seems fair to say that having a certain balance and diversity of microbes in the colon can have effects on constipation. Furthermore, when it comes to dietary aspects, prebiotics and probiotics could be helpful. However, when it comes to these factors the data is very limited. Furthermore, when it comes to eating fibrous foods or even fiber supplements, and their effects on the microbiome and subsequently on constipation, there is currently no data on what effect this will have.

Based on the current evidence, it seems premature to have a clear stance on what diet is best for the microbiome (McBurney et al 2019). Furthermore, it is not clear if fiber is needed to have a healthy microbiome. If it is, it is still not clear on how much and what type is needed. Could just a small amount of fiber, say about 10 grams, particularly soluble types, which could easily be achieved with a half a cup of lentils (7 grams) and a medium apple (4 grams) be enough? Also, there are likely other lifestyle factors that affect the microbiome, such as exercise and sleep (Benedict et al 2016; Chandrakumaran et al 2016; Davies et al 2014). These other lifestyle factors, besides fiber intake, could be enough to keep the microbiome healthy. Lots of unanswered questions at this time.

The “establish a consistent bathroom routine” (2:44) recommendation.

I think this is a common suggestion. However, of the four main papers used here (Paré et al. 2007; Bove, A., et al 2012; Forootan, M., et al. 2018; Black, C. J., & Ford, A. C. 2018), only one of them mentions this and it is not very supportive of it. Bove and colleagues state; 

“Defecation habits: Patients with chronic constipation are often instructed to defecate when the need is felt and to try to defecate at the same time every day, ideally upon awakening and after meals, when the colonic motor activity is highest. This recommendation is based on the observation that many people with normal colonic activity routinely defecate at the same time each day[4]. Trials evaluating this recommendation in constipated patients are also lacking.” (p.4995)

Again, this is one of those things that could help and seems unlikely to cause any physical harm. But currently there is no quality evidence to support that recommendation.

Finally, I want to briefly discuss the anecdote aspect as this I felt this was a major aspect of the presentation by Steve.

I think we have to be very careful with knowing that something “worked” from our experience with clients and even ourselves. I am not dismissing the “in the trenches” stuff that we can learn over the years (I have been in the health promotion field for over 20 years and I hope during this time I have acquired some useful information from hundreds of hours working with clients). Furthermore, evidence-based practice (EBP) is not solely about what has been studied and published. Rather it is a combination of three fundamental and overlapping components, (1) best external evidence, (2) client values/expectations and (3) individual clinical experience. And, of course, within the external evidence part, there is a hierarchy of evidence. However, when it comes to anecdotal/personal observation data/info, there are a multitude of potential pitfalls, such as;

  • Sample size
  • Correlation versus causation
  • Regression to the mean- the person could be feeling off for a few days, tries the new “intervention” and things get better, the question is how do we know the person was not going to get better anyways?
  • Single or multiple interventions? Did the person change many things at one, such as some aspect of eating, as well as doing some type of relaxation technique and drinking more fluid? Which “one” caused the change?
  • Placebo effect, this can have huge effects
  • Confirmation bias
  • People lie
  • Confabulation

There are many more (McRaney; Chabris & Simons; Kahneman). What clients experience and what we notice with clients can be valuable. However, due to how our three pounds of grey matter works, it seems we need to be very careful with this type of info/data.  

Well that was longer than I anticipated. As I explored the different lifestyle aspects it led me down some rabbit holes. Therefore, to cover the topic thoroughly I felt it was necessary to include a lot of different parts and a good amount of detail. My overarching take home messages from this piece. Be clear about the evidence, be careful with anecdotes, and just because it is a common recommendation, it’s still a good idea to check to see that there is actually good evidence for it. Although lifestyle factors are a common recommendation for the prevention and treatment of constipation, at this time the evidence is generally absent of any quality evidence or only some weak evidence showing benefit. Most importantly, of course, exercise regularly, eat healthy and cultivate a flexible and growth oriented mindset even if it doesn’t help you poop better. 



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Constipation and Lifestyle Habits: A Review of the Evidence
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