Obesity Associated With Abnormal Bowel Habits—Not Diet

Obesity or excess weight is considered to be a complex disease. Obesity is a medical problem in which a person suffers from large amount of body fat which enhances the risk of acquiring other chronic diseases such as heart problems, diabetes, gastrointestinal disorders, high blood pressure, cancer (in some cases), etc.

Most common causes of abnormal increase in weight or obesity are consumption of foods high in fats and calories, an inactive lifestyle, improper sleep, genetics, growing older, pregnancy (weight gained during pregnancy can be difficult to lose which may eventually lead to obesity), medical conditions such as PCOS (polycystic ovary syndrome), hypothyroidism (underactive thyroid), osteoarthritis, etc.

According to CDC, body mass index (BMI) is a person’s weight in kilograms divided by the square of height in meters. “Factors such as age, sex, ethnicity, and muscle mass can influence the relationship between body mass index (BMI) and body fat.

Also, remember, BMI doesn’t distinguish between excess fat, muscle, or bone mass, nor does it provide any indication of the distribution of fat among individuals.”

According to the Centers for Disease Control and Prevention (CDC), obesity affects about 40 percent of Americans.

It is found that the prevalence of obesity in children with irritable bowel syndrome (IBS) can range from about 24% to 42% and in adults the prevalence of IBS in obese subjects varied from 11% to about 24%, depending on the study population.

Association Between Obesity And Abnormal Bowel Habits

In the United States, approximately one-third of adults of the total population are found to be obese whereas irritable bowel syndrome (IBS), a chronic bowel disorder, has been found to occur in up to 20% of adults in the United States.

In a recent study, published by Alimentary Pharmacology & Therapeutics by a team of physician-researchers at Beth Israel Deaconess Medical Center (BIDMC), the association between obesity and chronic diarrhea was explained to be independent of a person’s dietary habit, daily activities or lifestyle, psychological factors or associated medical conditions.

This amazing study confirms - “a positive association between obesity and chronic diarrhea and reveals for the first time that this relationship is not driven by confounding factors such as diet or physical activity level”.

In the United States, National Health and Nutrition Examination Survey (NHANES), a program of studies administered by the CDC, was designed to assess the adult and children nutritional status and health in 2009-2010. For this analysis, Sarah Ballou, Ph.D., a health psychologist in the Division of Gastroenterology, Hepatology, and Nutrition at BIDMC and colleagues studied and analyzed 5,126 bowel health questionnaire responses of patients who were above 20 years of age and had no history of conditions such as irritable bowel syndrome, celiac disease or colon cancer.

The study involved the comparing bowel habits and body mass index (BMI), thereby dividing the BMI into the following categories: underweight (BMI<18.5), normal weight (BMI between 18.5?24.9), overweight (BMI between 25.0?29.9), obese (BMI between 30?34.9), and severely obese (BMI>35).  

It was observed by the team that after controlling for dietary, physical activity, diabetes, laxative use, and demographic factors, the respondents who were obese or severely obese had 60 percent higher chances of suffering from chronic diarrhoea compared to those with normal bowel habits or constipation.

Researchers believe that there might be some relationship between obesity and chronic low-grade inflammation, which may contribute to diarrhea.

"Clinicians should be aware of the relationship between obesity and diarrhea, especially considering the potential negative impacts altered bowel habits can have on quality of life" said Anthony Lembo, MD, a gastroenterologist in the Division of Gastroenterology, Hepatology, and Nutrition at BIDMC.

More studies in future might clarify this link and might also help in determining how obesity leads to inflammation and this could also serve as a base for physicians to improve their approach in treating abnormal bowel habits within this patient population.