In the January 2005 issue of the American Journal of Gastroenterology, Stefan Müller-Lissner, MD, challenged many of the long-held beliefs regarding chronic constipation. For example, fiber decreases transit time and stool mass in healthy individuals, but little evidence suggests that lack of dietary fiber causes chronic constipation. Fiber may benefit a subgroup of patients with less severe symptoms, but it may exacerbate already severe symptoms. Fluid intake may be useful for treating constipation in patients who are dehydrated; otherwise, minimal evidence shows that increasing fluid ingestion can have a clinically relevant impact.
Increased physical activity does not appear to significantly ameliorate constipation in otherwise healthy young adults, but increased activity may be beneficial, along with other measures, for treating constipation in the elderly. Stimulant laxatives at normal doses do not appear to be harmful to the colon, and no data indicate that their use is a risk factor for colorectal cancer. Lastly, there is no physiologic basis supporting concern about dependence on or addiction to stimulant laxatives in otherwise healthy patients; however, long-term use is not recommended, and patients with comorbid psychiatric disorders are more likely to misuse them.