Title: Intestinal Dysbiosis

Key words: malabsorption, bacterial, fungal, leaky gut syndrome, susceptibility, fermentation

Date: Oct 2000

Category: 8. The Gut

Type: Article

Author: Dr C Forsyth



Intestinal Dysbiosis


Dysbiosis is the term given to imbalance of the normal gastrointestinal flora and may be either bacterial or fungal.


Dysbiosis may cause:

        Malabsorption - nutritional deficiencies

        Leaky gut syndrome

        Increased susceptibility to intestinal pathogens

        Local symptoms of increased fermentation



Major Causes of Small Intestinal Bacterial Overgrowth


        Poor diet/nutritional status (esp. high fat and simple carbohydrates)



        Diabetes mellitus

        Immunodeficiency syndromes, esp. sIgA deficiency

        Abnormal gut motility

        Hypochlorhydria, achlorhydria, drug-induced hypoacidity

        Pancreatic exocrine insufficiency - chronic pancreatitis etc.

        Intestinal parasites e.g. Giardiasis

        Intestinal adhesions

        Stasis due to structural changes - diverticular disease, blind loops, radiation damage

        Other drug therapies

        Presence of xenobiotics

        Increased small intestinal pH

        Mercury from amalgam restorations



Commonly associated with Small Intestinal Bacterial Overgrowth:

Crohn's disease

Systemic lupus erythematosus




Hydrogen breath test (more sensitive than GFP for bacterial overgrowth) Biolab recommended.

Gut fermentation profile (GFP) (measurement of bacterial and yeast fermentation products- short chain fatty acids and alcohols in blood 1 hour after an oral glucose load) Biolab.

Treatment of Bacterial Overgrowth:


Identification and treatment of predisposing factors

Identification and treatment of secondary effects

Natural anti-bacterial agents -citrus seed extract, berberis concentrate, etc.

Probiotics (Lactobacillus acidophilus & L. bifidus)

Prebiotics (fructo-oligosaccharides, Inulin)

Conventional antibiotics