Good Bacteria Heal the Gut

Trillions of microbes live in the human gut, and scientists are learning more and more about how important these organisms are for our health.  When there are plenty of good bacteria and relatively few harmful bacteria living in the gut, the health of the host is improved in many ways. For one thing, researchers have found in mice that certain good bacteria protect the mice from gut inflammation.1

How do good bacteria protect against inflammation?

One of the best understood ways that good bacteria protect against inflammation is by breaking down fiber! Yes, when good bacteria break down fiber, they create short-chain fatty acids (SCFAs), and SCFAs help the gut in a number of ways.

For example, researchers think SCFAs do the following:

  • nourish the cells that line the gut2-5
  • normalize the body’s balance of pro- and anti-inflammatory mediators4, 6-8
  • reduce the permeability of the gut lining (reduces flow of irritants into gut tissue)2
  • help the gut lining to repair itself4
  • improve the acidity level of the gut3, 9
  • increase blood circulation in the gut tissue2
  • reduce cell loss caused by neutrophils2


  1. Velasquez-Manoff M. Gut Microbiome: The Peacekeepers. Nature 2015;518:S3-S11.
  2. Hallert C, Björck I, Nyman M, et al. Increasing fecal butyrate in ulcerative colitis patients by diet: controlled pilot study. Inflamm Bowel Dis 2003;9:116-121.
  3. Kanauchi O, Suga T, Tochihara M, et al. Treatment of ulcerative colitis by feeding with germinated barley foodstuff: first report of a multicenter open control trial. J Gastroenterol 2002;37:67-72.
  4. Kanauchi O, Iwanaga T, Mitsuyama K. Germinated barley foodstuff feeding. Digestion 2001;63:60-67.
  5. Nagy-Szakal D, Hollister EB, Luna RA, et al. Cellulose Supplementation Early in Life Ameliorates Colitis in Adult Mice. PloS one 2013;8:e56685.
  6. Faghfoori Z, Navai L, Shakerhosseini R, et al. Effects of an oral supplementation of germinated barley foodstuff on serum tumour necrosis factor-α, interleukin-6 and-8 in patients with ulcerative colitis. Ann Clin Biochem 2011;48:233-237.
  7. Steed H, Macfarlane GT, Blackett KL, et al. Clinical trial: the microbiological and immunological effects of synbiotic consumption–a randomized double‐blind placebo‐controlled study in active Crohn’s disease. Aliment Pharm Therap 2010;32:872-883.
  8. Benjamin JL, Hedin CRH, Koutsoumpas A, et al. Randomised, double-blind, placebo-controlled trial of fructo-oligosaccharides in active Crohn’s disease. Gut 2011;60:923-929.
  9. Welters CFM, Erik Heineman MD, Thunnissen FBJM, et al. Effect of dietary inulin supplementation on inflammation of pouch mucosa in patients with an ileal pouch-anal anastomosis. Dis Colon Rectum 2002;45:621-627.