How do probiotics work to provide greater health?

The primary way probiotics provide greater health is by maintaining a healthy environment within our gastrointestinal tract. Under normal conditions this balanced intestinal ecosystem prevents the overgrowth of harmful bacteria, viruses and fungi. When this delicate balance is disturbed the body can be predisposed toward infectious, allergic (e.g. eczema, rhinitis and asthma) and immuno-inflammatory (e.g. Chrohn’s disease, ulcerative colitis, diabetes and arthritis) illnesses.1 The incidence of these illnesses is increasing at an alarming rate in North America and other Industrial societies.1 One of the most common ways in which the microflora balance is disturbed is by improper diet; one that is high in sugars, grains, refined carbohydrates, alcohol, artificial sweeteners and preservatives and low in fresh fruits, vegetables and fiber. Other factors causing imbalance are stress, illness, toxins, prescription and non-prescription drugs, and alcohol.

Probiotic bacteria also exert a powerful influence on the development and function of the human body through their metabolic activity and interaction with various systems (gastro-intestinal, immune, nervous and endocrine systems). Their interactions with the GI system enable us to better digest and absorb food, as well as develop our Gut Associated Lymph Tissue (GALT), the important front line of our immune system.2 Intestinal microflora also play a pivotal role in the development of our innate immune system. In addition, probiotics promote normal colonic blood flow, produce essential nutrients such as antioxidants, Vitamin K and B vitamins, and facilitate nutrient and mineral absorption, especially calcium, magnesium, potassium and zinc.3,4,5,6,7 Probiotics also degrade and detoxify carcinogenic (cancer causing) enzymes as well as hormones and drugs.8

Probiotic consumption has been shown to down-regulate overactive immune responses in subjects with autoimmune disorders (such as inflammatory bowel disease, allergies, asthma and atopic dermatitis) and to enhance specific aspects of immune function in healthy subjects.1 An inverse relationship has also been shown between the consumption of probiotics and the incidence of colon and breast cancer.1 Consumption of probiotics has also been reported to normalize total and LDL cholesterol levels.1 The ingestion of probiotics has been shown to normalize immune functions, reduce the incidence of pathogenic infections and suppress allergic diseases in human subjects.1


1. Gill H.S. and Guarner F. 2004. Probiotics and human health: a clinical perspective. Postgraduate Medical Journal. 80:516-526.

2. Isolauri E., Sutas Y., Kankaanpaa P., Arvilommi H., and Salminen S. 2001. Pobiotics:effects on immunity. American Journal of Clinical Nutrition. 73:444S-450S.

3. Topping D.L. and Clifton P.M. 2001. Short-chain fatty acids and human colonic function: roles of resistant starch and nonstarch polysaccharides. Physiological Reviews. 81:1031-1064.

4. Scharrer E. and Lutz T. 1990. Effects of short chain fatty acids and K on absorption of Mg and other cations by the colon and caecum. Z. Ernahrungswiss. 29:162-168.

5. Delzenne N., Aertssens J., Verplaetse H., Roccaro M., and Roberfroid M. 1995. Effect of fermentable fructooligosaccharides on mineral, nitrogen and energy balance in the rat. Life Sciences. 57:1579-1587.

6. Conway P. 2001. Prebiotics and human health: the state of the art and future perspectives. Scandanavian Journal of Nutrition. 45:13-21.

7. Bentley R. and Maganathan R. 1982. Biosynthesis of vitamin K (menaquinone) in bacteria. Microbiological Reviews. 46:241-280.

8. Rafter J. 2002. Lactic acid bacteria and cancer: mechanistic perspective. British Journal of Nutrition. 88 Supplement 1:S89-S94