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Date of last update: 10/21/2017.

Forum Name: Colon and Rectal Cancers

Question: Thin and loose stools -what can it be other than cancer?

 ynot25 - Sat Sep 20, 2008 1:24 am

I'm a 49 year old women and have over the past several months had thin (flat, but bigger than a pencil) and loose stools. I have a consultation appointment for a colonoscopy coming up this Monday. I am driving myself crazy with fear that I have colon cancer. I don't have any pain or seen any blood in my stools or the toilet bowl. I believe my great grandmother died of colon cancer in her 80's, no other known family history. I haven't had the best diet over the years, but have been adding more fruits, vegetables and fiber to my diet. I began taking a tablespoon of psyllium every day a little more than a year ago. I don't recall having any issues with my bowels and began taking the psyllium as a way to add fiber, but found my bowel movements to be really good until a few months ago with the added fiber. I have had 3 bouts of pain over the past 3 years in the lower left abdomin area after eating an apple. My doctor said possibly diverticulitis. I have had a scan of my abdominal area...they found a possible cyst on my kidney, so I then went for a CT which showed the same thing, but smaller in size.

Back to my questions, are there any other conditions that would cause thin and loose stools? Is it possible that polyps can grow to a size that would cause a thin stool?

Also, one more question...should stools float or sink?

I appreciate any help you can give me.
 Dr. Safaa Mahmoud - Sat Oct 11, 2008 7:36 am

User avatar Hello,
Causes of loose stool (change in consistency) and diarrhea (increased in frequency too) include Irritable bowel syndrome IBS, food intolerance, inflammatory changes in the wall of the intestine and malabsorption.

Psyllium is mainly used as a dietary fiber, which is not absorbed by the small intestine. Mechanism of action involves excess water absorption and stimulating normal bowel elimination. One of the minor side effects of psyllium is diarrhea and loose stool, especially with sufficient water intake.

In food intolerance, symptoms occur after ingestion of certain types of food like Lactose intolerance and Gluten intolerance.

Irritable bowel syndrome IBS is believed to be due to autonomic dysfunction or hormonal imbalance that can be easily controlled by simple changes in the lifestyle, diet. Certain types of foods contain, chocolate, milk and alcohol might aggravate the condition. Stress increases the frequency and the severity of symptoms in almost all cases. Diagnosis is made by exclusion of other causes.

Other causes to be excluded although less likely:
- Colitis due to infectious or inflammatory disorders, it is usually associated pain and tender abdomen.
- Appendicitis, pain and tenderness usually present and in the right iliac fossa.

Changes in bowel habits are always alarming and should be properly investigated. Tumors in the colon should be excluded considering your positive family history.

Investigations include:
Stool analysis and careful microscopic study . Stool culture is also important. Estimation of fat content in stools is also useful.

I advise you to follow up with your doctor.
Please keep us updated.
Best regards.

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