Ten years ago few people had heard of probiotics although they were regularly consumed in foods like yoghurt. Now, the term is more familiar, the number of probiotic products is increasing and growing scientific evidence shows that they may benefit to our health. So what are probiotics and how can they benefit our health?
Where do probiotics come in?
Many species of bacteria work together in the human gut to maintain its normal function. Factors such as stress or a course of antibiotics can, however, upset this natural bacterial balance and shift it away from beneficial organisms like lactobacilli and bifidobacteria towards harmful bacteria. This shift can leave you more susceptible to food-borne infections such as those caused by Salmonella, E. coli and Listeria. It may also predispose you towards disorders of the gut like bowel cancer and ulcerative colitis(1). This is where probiotics come in. Probiotics are living micro-organisms (such as lactic acid bacteria and bifidobacteria), which, when consumed regularly in sufficient quantities, modify the bacterial balance in your gut and have beneficial health effects. Probiotics can be added to foods such as yoghurts and other fermented milk products, or be taken as supplements - so they are now common in shops and supermarkets.
Therapeutic possibilities
The scientific concept behind probiotics is now accepted, but clinical trial work has only recently started to test the ability of probiotic preparations to prevent or treat specific diseases, for example: gut inflammation, gut infection or cancer(2). Positive effects reported include:
- prevention of acute diarrhoea in children
- amelioration of diarrhoea associated with using
- control of symptoms of inflammatory bowel conditions like Crohn's disease and irritable bowel syndrome
- boosting the immune system
- reducing allergies in the newborn.
PROEUHEALTH
This promising early work paved the way for a major scientific initiative known as PROEUHEALTH involving research partners from 16 European countries. This cluster of projects aims to better understand how probiotics can contribute to health and well-being(3). One important area of research is to determine which bacteria are actually present in the healthy gut and how this changes with age, diet, lifestyle, and in response to chronic disease. Since the effects of probiotics are strain specific, PROEUHEALTH data, together with results from previous research, will help to determine which bacteria exactly can improve the natural defence system and/or prevent specific diseases(3). The output from the EU research platform will hopefully underpin the development of many therapeutic probiotics and make it possible to tailor products for particular age ranges or lifestyles.
Probiotics for health and well-being
Probiotic foods (e.g. yoghurts and drinks) are an increasingly popular way to improve general health and well-being. In view of this popularity, the public needs guarantees that these products are safe and effective. More evidence is required to demonstrate the exact health effects of specific preparations and to verify that they are completely safe when consumed in the long term. However, guidelines already exist to ensure that probiotic foods contain safe bacterial strains and that the appropriate studies have been carried out show a beneficial effect in the body(4). Stringent European guidelines on health claims will soon provide further protection and reassurance to consumers around specific information on how probiotic products are 'good for them'.
Just the beginning
Early work has demonstrated that probiotics have a real effect on the gut bacteria and that there is much potential regarding their health effects. Exciting work is soon to be published from the PROEUHEALTH project, which will improve the quality and safety of probiotics and enables the development of more targeted products in the future.
References
- Fooks LR & Gibson GR (2002) Probiotics as modulators of the gut flora. British Journal of Nutrition 88 (Suppl 1) S39-S49
- FAO/WHO (2001) Health and Nutritional Properties of Probiotics in Food including Powder Milk with Live Lactic Acid Bacteria. www.fao.org
- The Food, GI tract functionality and Human health cluster. Visit virtual.vtt.fi/virtual/proeuhealth/ for updates on latest research news
- FAO/WHO (2002) Guidelines for the Evaluation of Probiotics in Food. www.fao.org
FOOD TODAY 01/2006
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