Dietary Considerations for Patients with Constipation

Approximately 20% of the population is affected by IBS. When looking at IBS with constipation specifically, how important is diet in relieving symptoms? Is there a specific type of diet recommended for patients to consider?

Dr. Menees: Dietary therapy can be really important for patients with IBS. It’s something they can control, and it can be empowering to them. When I first meet a patient with IBS, I always take a diet history. I want to know what they're putting in their mouth including the beverages that they are drinking.

When it comes to IBS, for a long time, fiber has been first-line treatment, particularly when constipation is the predominant complaint. As you know, fiber is classified into 2 different categories: soluble and insoluble. The soluble fiber is found in psyllium, oat bran, barley, and beans, whereas the insoluble fiber is found in wheat bran, some vegetables, and whole grains.

Soluble fiber exerts its laxative effect as it is hydrophilic, so it brings the water to the stool and increases the stool water content. It also resists colonic fermentation. Insoluble fiber is fermentable and loses its water holding capacity, produces gas that aggravates patients with bloating and flatulence. I always recommend soluble fiber.

When we're thinking about those properties that I just described, the ability to improve stool viscosity and frequency argues for the use of fiber in patients with IBS-C, although there are few studies to support this. There have been a lot of trials, but only a few that have been done within  IBS-C patients. The most recent meta-analysis was done by Moayyedi and colleagues. Here they looked at 15 RCTs of which only 6 had sub-typed the different types of IBS that were in the trials. Only 2 were IBS-C. So, the key takeaway for this meta-analysis was that-- and per the ACG guidelines-- the use of soluble, viscous, nonfermentable fiber provides benefits for global IBS symptoms.

There's also a general lack of side effects with this intervention. It’s important to instruct patients to titrate up on the soluble fiber slowly. Soluble fiber is a very reasonable first-line therapy for patients with IBS.

There are other dietary interventions that we can talk about. In 2015, the National Institute for Health Care Excellence issued their own IBS guideline recommendations. These are common sense things that I discuss with my patients, such as moderation in their diet: don't drink too much alcohol or don't drink too much caffeine. I go over these with patients as the guidelines specifically talk about soluble fiber. It can be helpful for patients to look at what they're doing on a daily basis.

The other important dietary intervention that we have utilized in IBS is the low-FODMAP diet.  This diet is based on restricting fermentable carbohydrates that bacteria work on, producing short chain fatty acids which cause an osmotic shift, bringing water into the colon, producing gases that lead to luminal dissension, and triggering meal-related symptoms in patients with IBS.

A recent meta-analysis of 7 randomized clinical trials looked at low FODMAP diet versus several different comparators. The low-FODMAP diet was associated with a significant reduction in global IBS symptoms compared with the different comparators. However, there are no data on a low-FODMAP diet strictly in IBS-C patients. So, stay tuned on that. We are doing a trial in IBS-C only.

If you are planning on using the low-FODMAP diet in your IBS patients, it's also important to utilize a GI trained dietician, because it can be overwhelming for patients to figure out what's an oligosaccharides, disaccharide, monosaccharides, and polyols. Having a wealth of knowledge available to these patients is critical.

Are there recent studies that show the effectiveness of diet as an approach to managing patients with IBS/CIC and what has been your in-practice experience?

Dr. Menees: Yes.  For IBS and CIC, the initial approach, which is soluble fiber, is what I use in practice for both disorders. However, that response can vary between the 2 conditions, and the next step you chose varies by the disorder.

As far as for my patients, soluble fiber is well accepted, but I do make sure that they are adequately hydrated. Hydration alone doesn't seem to change the incidence of constipation for patients, although there is some evidence for mineral water. Believe it or not, there are 3 randomized controlled trials showing the efficacy of mineral water in patients with CIC. However, it's also important in the chronic constipation patients that you find out how often they're having a bowel movement. If they are having a bm every 7 to 10 days, I'm afraid that fiber will actually worsen their symptoms. In those patients, fiber will not be my first-line treatment.

As far as other dietary options that I use specifically in patients with CIC, we now have data for fruit fibers. Specifically, we have data for prunes and kiwifruit, both green and golden kiwifruit. Chey and colleagues compared the efficacy of psyllium, 2 green kiwi per day, and prunes, 6 twice-daily in patients with CIC.  All 3 arms - kiwifruit (45%), psyllium (64%) and prunes (67%)- were found to be effective. Despite the primary endpoint results, patients randomized to the kiwi arm were most likely to be satisfied with treatment compared to the other arms. There was another trial performed in 32 patients, comparing the gold kiwifruit to psyllium. The kiwifruit resulted in significant improvement in BM frequency and GI discomfort as compared to psyllium. I use all of these as tools for my patients in clinical practice. 

We talked about symptoms, but how important is diet in preventing other diseases or conditions in patients with IBS-C?

Dr. Menees: For diet management, since soluble fibers are the gold standard and our first-line treatment, I discuss the general health benefits of fiber. Fiber is associated with reduced cardiovascular mortality, stroke, diabetes, and colorectal cancer. So that's important.

Being on a high fiber diet can improve the patient's overall general health. It is also helpful for other GI diseases. It helps reduce the risk of diverticulitis and diverticular bleeding. People who are on a high fiber diet are the least likely to have fecal incontinence. These are all excellent benefits of one of our first-line treatments.

Are there first-line therapies you recommend in conjunction with diet to help?

Dr. Menees: When it comes to chronic intermittent constipation, I certainly use osmotic laxatives after at least a 6- to 8-week trial of fiber. When you're adding fiber to your diet, its important to add slowly, about 5 grams per week.

I also tell the patient that it's not going to be quick. It takes at least 6 to 8 weeks for it to kick in. I will use osmotics, PEG 3350 and milk of magnesia which are very cheap and over the counter if they're not reaching the stool consistency and frequency. I also use stimulant and laxatives in my chronic intermittent constipation.

Now, for IBS, PEG 3350 osmotic laxatives are not recommended as it only changes stool frequency, but it has no impact on abdominal discomfort or abdominal pain. For IBS patients, I will utilize the secretagogues, the chloride channel activator, such as lubiprostone or guanylate cyclase activator, such as linaclotide or plecanatide.

Are there specific demographics more susceptible to constipation? What are your standards for dietary considerations for these populations? 

Dr. Menees: There are specific demographics that are susceptible to constipation. Women are more likely than men to have constipation. Women have a longer colon due to reproductive organs. This increases the surface area for absorption of water, which can predispose women to constipation.

In the US and UK, self-reported constipation is definitely more prevalent in women and those over age 60. When you adjust for those factors, you'll see it in patients who have low income, poor education, and little physical activity.

We also know that the prevalence of chronic constipation rises with age, and most dramatically in patients who are 65 and older. Over a quarter of males and almost a third of females will complain of constipation. Now, this age factor can be  compounded by other medical problems, such as hypertension. Additionally, in those over 65, there seems to be a correlation with decreased calories, but not with fluid or fiber.

Other populations that one must consider include any neurologic diseases, such as Parkinson Disease. We have to think of patients with chronic pain as they can be on opioids. But even those with chronic pain who are not on opioids will be on NSAIDs, which can also cause constipation. There are many different factors that make patients susceptible to constipation.

Approximately 20% of the population is affected by IBS. When looking at IBS with constipation specifically, how important is diet in relieving symptoms? Is there a specific type of diet recommended for patients to consider?

Dr. Menees: Dietary therapy can be really important for patients with IBS. It’s something they can control, and it can be empowering to them. When I first meet a patient with IBS, I always take a diet history. I want to know what they're putting in their mouth including the beverages that they are drinking.

When it comes to IBS, for a long time, fiber has been first-line treatment, particularly when constipation is the predominant complaint. As you know, fiber is classified into 2 different categories: soluble and insoluble. The soluble fiber is found in psyllium, oat bran, barley, and beans, whereas the insoluble fiber is found in wheat bran, some vegetables, and whole grains.

Soluble fiber exerts its laxative effect as it is hydrophilic, so it brings the water to the stool and increases the stool water content. It also resists colonic fermentation. Insoluble fiber is fermentable and loses its water holding capacity, produces gas that aggravates patients with bloating and flatulence. I always recommend soluble fiber.

When we're thinking about those properties that I just described, the ability to improve stool viscosity and frequency argues for the use of fiber in patients with IBS-C, although there are few studies to support this. There have been a lot of trials, but only a few that have been done within  IBS-C patients. The most recent meta-analysis was done by Moayyedi and colleagues. Here they looked at 15 RCTs of which only 6 had sub-typed the different types of IBS that were in the trials. Only 2 were IBS-C. So, the key takeaway for this meta-analysis was that-- and per the ACG guidelines-- the use of soluble, viscous, nonfermentable fiber provides benefits for global IBS symptoms.

There's also a general lack of side effects with this intervention. It’s important to instruct patients to titrate up on the soluble fiber slowly. Soluble fiber is a very reasonable first-line therapy for patients with IBS.

There are other dietary interventions that we can talk about. In 2015, the National Institute for Health Care Excellence issued their own IBS guideline recommendations. These are common sense things that I discuss with my patients, such as moderation in their diet: don't drink too much alcohol or don't drink too much caffeine. I go over these with patients as the guidelines specifically talk about soluble fiber. It can be helpful for patients to look at what they're doing on a daily basis.

The other important dietary intervention that we have utilized in IBS is the low-FODMAP diet.  This diet is based on restricting fermentable carbohydrates that bacteria work on, producing short chain fatty acids which cause an osmotic shift, bringing water into the colon, producing gases that lead to luminal dissension, and triggering meal-related symptoms in patients with IBS.

A recent meta-analysis of 7 randomized clinical trials looked at low FODMAP diet versus several different comparators. The low-FODMAP diet was associated with a significant reduction in global IBS symptoms compared with the different comparators. However, there are no data on a low-FODMAP diet strictly in IBS-C patients. So, stay tuned on that. We are doing a trial in IBS-C only.

If you are planning on using the low-FODMAP diet in your IBS patients, it's also important to utilize a GI trained dietician, because it can be overwhelming for patients to figure out what's an oligosaccharides, disaccharide, monosaccharides, and polyols. Having a wealth of knowledge available to these patients is critical.

Are there recent studies that show the effectiveness of diet as an approach to managing patients with IBS/CIC and what has been your in-practice experience?

Dr. Menees: Yes.  For IBS and CIC, the initial approach, which is soluble fiber, is what I use in practice for both disorders. However, that response can vary between the 2 conditions, and the next step you chose varies by the disorder.

As far as for my patients, soluble fiber is well accepted, but I do make sure that they are adequately hydrated. Hydration alone doesn't seem to change the incidence of constipation for patients, although there is some evidence for mineral water. Believe it or not, there are 3 randomized controlled trials showing the efficacy of mineral water in patients with CIC. However, it's also important in the chronic constipation patients that you find out how often they're having a bowel movement. If they are having a bm every 7 to 10 days, I'm afraid that fiber will actually worsen their symptoms. In those patients, fiber will not be my first-line treatment.

As far as other dietary options that I use specifically in patients with CIC, we now have data for fruit fibers. Specifically, we have data for prunes and kiwifruit, both green and golden kiwifruit. Chey and colleagues compared the efficacy of psyllium, 2 green kiwi per day, and prunes, 6 twice-daily in patients with CIC.  All 3 arms - kiwifruit (45%), psyllium (64%) and prunes (67%)- were found to be effective. Despite the primary endpoint results, patients randomized to the kiwi arm were most likely to be satisfied with treatment compared to the other arms. There was another trial performed in 32 patients, comparing the gold kiwifruit to psyllium. The kiwifruit resulted in significant improvement in BM frequency and GI discomfort as compared to psyllium. I use all of these as tools for my patients in clinical practice. 

We talked about symptoms, but how important is diet in preventing other diseases or conditions in patients with IBS-C?

Dr. Menees: For diet management, since soluble fibers are the gold standard and our first-line treatment, I discuss the general health benefits of fiber. Fiber is associated with reduced cardiovascular mortality, stroke, diabetes, and colorectal cancer. So that's important.

Being on a high fiber diet can improve the patient's overall general health. It is also helpful for other GI diseases. It helps reduce the risk of diverticulitis and diverticular bleeding. People who are on a high fiber diet are the least likely to have fecal incontinence. These are all excellent benefits of one of our first-line treatments.

Are there first-line therapies you recommend in conjunction with diet to help?

Dr. Menees: When it comes to chronic intermittent constipation, I certainly use osmotic laxatives after at least a 6- to 8-week trial of fiber. When you're adding fiber to your diet, its important to add slowly, about 5 grams per week.

I also tell the patient that it's not going to be quick. It takes at least 6 to 8 weeks for it to kick in. I will use osmotics, PEG 3350 and milk of magnesia which are very cheap and over the counter if they're not reaching the stool consistency and frequency. I also use stimulant and laxatives in my chronic intermittent constipation.

Now, for IBS, PEG 3350 osmotic laxatives are not recommended as it only changes stool frequency, but it has no impact on abdominal discomfort or abdominal pain. For IBS patients, I will utilize the secretagogues, the chloride channel activator, such as lubiprostone or guanylate cyclase activator, such as linaclotide or plecanatide.

Are there specific demographics more susceptible to constipation? What are your standards for dietary considerations for these populations? 

Dr. Menees: There are specific demographics that are susceptible to constipation. Women are more likely than men to have constipation. Women have a longer colon due to reproductive organs. This increases the surface area for absorption of water, which can predispose women to constipation.

In the US and UK, self-reported constipation is definitely more prevalent in women and those over age 60. When you adjust for those factors, you'll see it in patients who have low income, poor education, and little physical activity.

We also know that the prevalence of chronic constipation rises with age, and most dramatically in patients who are 65 and older. Over a quarter of males and almost a third of females will complain of constipation. Now, this age factor can be  compounded by other medical problems, such as hypertension. Additionally, in those over 65, there seems to be a correlation with decreased calories, but not with fluid or fiber.

Other populations that one must consider include any neurologic diseases, such as Parkinson Disease. We have to think of patients with chronic pain as they can be on opioids. But even those with chronic pain who are not on opioids will be on NSAIDs, which can also cause constipation. There are many different factors that make patients susceptible to constipation.

Approximately 20% of the population is affected by IBS. When looking at IBS with constipation specifically, how important is diet in relieving symptoms? Is there a specific type of diet recommended for patients to consider?

Dr. Menees: Dietary therapy can be really important for patients with IBS. It’s something they can control, and it can be empowering to them. When I first meet a patient with IBS, I always take a diet history. I want to know what they're putting in their mouth including the beverages that they are drinking.

When it comes to IBS, for a long time, fiber has been first-line treatment, particularly when constipation is the predominant complaint. As you know, fiber is classified into 2 different categories: soluble and insoluble. The soluble fiber is found in psyllium, oat bran, barley, and beans, whereas the insoluble fiber is found in wheat bran, some vegetables, and whole grains.

Soluble fiber exerts its laxative effect as it is hydrophilic, so it brings the water to the stool and increases the stool water content. It also resists colonic fermentation. Insoluble fiber is fermentable and loses its water holding capacity, produces gas that aggravates patients with bloating and flatulence. I always recommend soluble fiber.

When we're thinking about those properties that I just described, the ability to improve stool viscosity and frequency argues for the use of fiber in patients with IBS-C, although there are few studies to support this. There have been a lot of trials, but only a few that have been done within  IBS-C patients. The most recent meta-analysis was done by Moayyedi and colleagues. Here they looked at 15 RCTs of which only 6 had sub-typed the different types of IBS that were in the trials. Only 2 were IBS-C. So, the key takeaway for this meta-analysis was that-- and per the ACG guidelines-- the use of soluble, viscous, nonfermentable fiber provides benefits for global IBS symptoms.

There's also a general lack of side effects with this intervention. It’s important to instruct patients to titrate up on the soluble fiber slowly. Soluble fiber is a very reasonable first-line therapy for patients with IBS.

There are other dietary interventions that we can talk about. In 2015, the National Institute for Health Care Excellence issued their own IBS guideline recommendations. These are common sense things that I discuss with my patients, such as moderation in their diet: don't drink too much alcohol or don't drink too much caffeine. I go over these with patients as the guidelines specifically talk about soluble fiber. It can be helpful for patients to look at what they're doing on a daily basis.

The other important dietary intervention that we have utilized in IBS is the low-FODMAP diet.  This diet is based on restricting fermentable carbohydrates that bacteria work on, producing short chain fatty acids which cause an osmotic shift, bringing water into the colon, producing gases that lead to luminal dissension, and triggering meal-related symptoms in patients with IBS.

A recent meta-analysis of 7 randomized clinical trials looked at low FODMAP diet versus several different comparators. The low-FODMAP diet was associated with a significant reduction in global IBS symptoms compared with the different comparators. However, there are no data on a low-FODMAP diet strictly in IBS-C patients. So, stay tuned on that. We are doing a trial in IBS-C only.

If you are planning on using the low-FODMAP diet in your IBS patients, it's also important to utilize a GI trained dietician, because it can be overwhelming for patients to figure out what's an oligosaccharides, disaccharide, monosaccharides, and polyols. Having a wealth of knowledge available to these patients is critical.

Are there recent studies that show the effectiveness of diet as an approach to managing patients with IBS/CIC and what has been your in-practice experience?

Dr. Menees: Yes.  For IBS and CIC, the initial approach, which is soluble fiber, is what I use in practice for both disorders. However, that response can vary between the 2 conditions, and the next step you chose varies by the disorder.

As far as for my patients, soluble fiber is well accepted, but I do make sure that they are adequately hydrated. Hydration alone doesn't seem to change the incidence of constipation for patients, although there is some evidence for mineral water. Believe it or not, there are 3 randomized controlled trials showing the efficacy of mineral water in patients with CIC. However, it's also important in the chronic constipation patients that you find out how often they're having a bowel movement. If they are having a bm every 7 to 10 days, I'm afraid that fiber will actually worsen their symptoms. In those patients, fiber will not be my first-line treatment.

As far as other dietary options that I use specifically in patients with CIC, we now have data for fruit fibers. Specifically, we have data for prunes and kiwifruit, both green and golden kiwifruit. Chey and colleagues compared the efficacy of psyllium, 2 green kiwi per day, and prunes, 6 twice-daily in patients with CIC.  All 3 arms - kiwifruit (45%), psyllium (64%) and prunes (67%)- were found to be effective. Despite the primary endpoint results, patients randomized to the kiwi arm were most likely to be satisfied with treatment compared to the other arms. There was another trial performed in 32 patients, comparing the gold kiwifruit to psyllium. The kiwifruit resulted in significant improvement in BM frequency and GI discomfort as compared to psyllium. I use all of these as tools for my patients in clinical practice. 

We talked about symptoms, but how important is diet in preventing other diseases or conditions in patients with IBS-C?

Dr. Menees: For diet management, since soluble fibers are the gold standard and our first-line treatment, I discuss the general health benefits of fiber. Fiber is associated with reduced cardiovascular mortality, stroke, diabetes, and colorectal cancer. So that's important.

Being on a high fiber diet can improve the patient's overall general health. It is also helpful for other GI diseases. It helps reduce the risk of diverticulitis and diverticular bleeding. People who are on a high fiber diet are the least likely to have fecal incontinence. These are all excellent benefits of one of our first-line treatments.

Are there first-line therapies you recommend in conjunction with diet to help?

Dr. Menees: When it comes to chronic intermittent constipation, I certainly use osmotic laxatives after at least a 6- to 8-week trial of fiber. When you're adding fiber to your diet, its important to add slowly, about 5 grams per week.

I also tell the patient that it's not going to be quick. It takes at least 6 to 8 weeks for it to kick in. I will use osmotics, PEG 3350 and milk of magnesia which are very cheap and over the counter if they're not reaching the stool consistency and frequency. I also use stimulant and laxatives in my chronic intermittent constipation.

Now, for IBS, PEG 3350 osmotic laxatives are not recommended as it only changes stool frequency, but it has no impact on abdominal discomfort or abdominal pain. For IBS patients, I will utilize the secretagogues, the chloride channel activator, such as lubiprostone or guanylate cyclase activator, such as linaclotide or plecanatide.

Are there specific demographics more susceptible to constipation? What are your standards for dietary considerations for these populations? 

Dr. Menees: There are specific demographics that are susceptible to constipation. Women are more likely than men to have constipation. Women have a longer colon due to reproductive organs. This increases the surface area for absorption of water, which can predispose women to constipation.

In the US and UK, self-reported constipation is definitely more prevalent in women and those over age 60. When you adjust for those factors, you'll see it in patients who have low income, poor education, and little physical activity.

We also know that the prevalence of chronic constipation rises with age, and most dramatically in patients who are 65 and older. Over a quarter of males and almost a third of females will complain of constipation. Now, this age factor can be  compounded by other medical problems, such as hypertension. Additionally, in those over 65, there seems to be a correlation with decreased calories, but not with fluid or fiber.

Other populations that one must consider include any neurologic diseases, such as Parkinson Disease. We have to think of patients with chronic pain as they can be on opioids. But even those with chronic pain who are not on opioids will be on NSAIDs, which can also cause constipation. There are many different factors that make patients susceptible to constipation.