Original Contribution

Functional GI Disorders

Characterizing Normal Bowel Frequency and Consistency in a Representative Sample of Adults in the United States (NHANES)

  • The American Journal of Gastroenterology volume 113, pages 115123 (2018)
  • doi:10.1038/ajg.2017.213
  • Download Citation
Received:
Accepted:
Published:

Abstract

Objectives:

Our current understanding of normal bowel patterns in the United States (US) is limited. Available studies have included individuals with both normal and abnormal bowel patterns, making it difficult to characterize normal bowel patterns in the US. The current study aims to (1) examine frequency and consistency in individuals with self-reported normal bowel habits and (2) determine demographic factors associated with self-reported normalcy.

Methods:

This study used data from adult participants who completed bowel health questions as part of the National Health and Nutrition Examination Survey (NHANES) in 2009–2010 and who reported normal bowel patterns (N=4,775). Data regarding self-perceived bowel health; stool frequency; stool consistency (using the Bristol Stool Form Scale (BSFS)); and demographic factors were analyzed.

Results:

95.9% of the sample reported between 3 and 21 BMs per week. Among men, 90% reported a BSFS between 3 and 5, while for women it was 2–6. After controlling for age, the following demographic variables were associated with normalcy: male sex, higher education, higher income, <2 daily medications, and high daily fiber intake. Hispanic ethnicity was significantly associated with abnormal self-reported bowel habits.

Conclusions:

This is the first study to evaluate normal bowel frequency and consistency in a representative sample of adults in the US. The current findings bolster the common “3 and 3” metric of normal frequency (3 BMs/day to 3 BMs/week) while also suggesting different criteria for normal consistency for men and women. Finally, this study provides novel information about demographic factors associated with normal frequency and consistency.

  • Subscribe to The American Journal of Gastroenterology for full access:

    $870

    Subscribe

Additional access options:

Already a subscriber?  Log in  now or  Register  for online access.

References

  1. 1.

    , , et al. Variation of bowel habit in two population samples. Proc R Soc Med 1966;59:11–12.

  2. 2.

    , , et al. Bowel patterns among subjects not seeking health care. Use of a questionnaire to identify a population with bowel dysfunction. Gastroenterology 1982;83:529–534.

  3. 3.

    , , et al. Self-perceived normality in defecation habits. Dig Liver Dis 2005;38:103–108.

  4. 4.

    , , et al. Bowel Disorders. Gastroenterology 150:1393–1407.e5.

  5. 5.

    , , et al. Cumulative incidence of chronic constipation: a population-based study 1988-2003. Aliment Pharmacol Ther 2007;26:1521–1528.

  6. 6.

    , , et al. Functional bowel disorders in Iranian population using Rome III criteria. Saudi J Gastroenterol 2010;16:154–160.

  7. 7.

    , , et al. Epidemiology of functional diarrhea and comparison with diarrhea-predominant irritable bowel syndrome: a population-based survey in China. PLoS ONE 2012;7:e43749.

  8. 8.

    , , . Detection of pseudodiarrhoea by simple clinical assessment of intestinal transit rate. BMJ 1990;300:439–440.

  9. 9.

    , . Stool form scale as a useful guide to intestinal transit time. Scand J Gastroenterol 1997;32:920–924.

  10. 10.

    , , et al. Stool characteristics and colonic transit in irritable bowel syndrome: evaluation at two time points. Scand J Gastroenterol 2013;48:295–301.

  11. 11.

    , , et al. Do stool form and frequency correlate with whole-gut and colonic transit? results from a multicenter study in constipated individuals and healthy controls. Am J Gastroenterol 2010;105:403–411.

  12. 12.

    , , . Validity and reliability of the Bristol Stool Form Scale in healthy adults and patients with diarrhoea-predominant irritable bowel syndrome. Aliment Pharmacol Ther 2016;44:693–703.

  13. 13.

    , , et al. Association of low dietary intake of fiber and liquids with constipation: evidence from the National Health and Nutrition Examination Survey. Am J Gastroenterol 2013;108:796–803.

  14. 14.

    , , et al. Insights into normal and disordered bowel habits from bowel diaries. Am J Gastroenterol 2008;103:692–698.

  15. 15.

    , . Analysis of Health Surveys. Wiley InterscienceBiometric Research Branch at the National Cancer Institute: Bethesda, MD. 1999.

  16. 16.

    , , et al. Defecation frequency and timing, and stool form in the general population: a prospective study. Gut 1992;33:818–824.

  17. 17.

    , , et al. The effect of fiber supplementation on irritable bowel syndrome: a systematic review and meta-analysis. Am J Gastroenterol 2014;109:1367–1374.

  18. 18.

    , , . Association between physical activity, fiber intake, and other lifestyle variables and constipation in a study of women. Am J Gastroenterol 2003;98:1790–1796.

  19. 19.

    , . Income and race/ethnicity influence dietary fiber intake and vegetable consumption. Nutr Res 2014;34:844–850.

  20. 20.

    . Basic mechanisms of the aging gastrointestinal tract. Dig Dis 2007;25:112–117.

  21. 21.

    . The aging gut: physiology. Clin Geriatr Med 2007;23:757–767 v-vi.

Download references

Author information

Affiliations

  1. Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA

    • Shuji Mitsuhashi
    • , Sarah Ballou
    • , Zhenghui G Jiang
    • , William Hirsch
    • , Judy Nee
    • , Johanna Iturrino
    • , Vivian Cheng
    •  & Anthony Lembo

Authors

  1. Search for Shuji Mitsuhashi in:

  2. Search for Sarah Ballou in:

  3. Search for Zhenghui G Jiang in:

  4. Search for William Hirsch in:

  5. Search for Judy Nee in:

  6. Search for Johanna Iturrino in:

  7. Search for Vivian Cheng in:

  8. Search for Anthony Lembo in:

Competing interests

Guarantor of the article: Anthony Lembo, MD.

Specific author contributions: The idea for the article was conceived by A.L and Z.G.J. The manuscript was drafted by S.B. and S.M. Statistical analysis was performed by S.M. and Z.G.J. The draft manuscript was critically reviewed by W.H., J.N., J.I, and V.C. All authors reviewed and approved the final version of the manuscript.

Financial support: This project was funded in part by T32DK007760.

Potential competing interests: None.

Corresponding author

Correspondence to Anthony Lembo.