What Are Probiotics?

By now, most people are aware of the mysterious ‘good bacteria’ that may help keep a regular digestive system and strengthen our immune system. But most people’s understanding doesn’t extend much further than the knowledge that certain yoghurts and supplements contain probiotics.

For the curious, here is a quick primer to probiotics – what they are, why supplement your diet with them and where to find them.

What are probiotics?

Although probably cooked up in a marketing department somewhere, the phrase ‘good bacteria’ is not wide of the mark.

Probiotics technically are micro-organisms that provide health benefits to the host. They are almost identical to what we traditionally refer to as bacteria – the sort that we blame for colds and more serious maladies – except that rather than causing us harm, they may serve to strengthen our bodies.

As with the term bacteria, ‘probiotics’ refers to a staggering number of micro-organisms and should be viewed as little more than a generic term. Research into the effects of particular strains of probiotics is still relatively nascent, but a couple have already stood out as being of potential benefit to us: Lacti acid bacteria (LAB) and Bifidobacteria.

Why might probiotics be good for me?

Aside from being potentially good for us by definition (if they are a micro-organism that confers no health benefit they are not a probiotic), probiotics are broadly thought to benefit us by strengthening our immune system and aiding our digestive health. Although as mentioned before, with research still continuing into different strains, we may find more specific uses in the future.

There are two theories behind the claim that probiotics may help strengthen the immune system. The first is that harmful pathogens often prefer an alkaline environment, and certain probiotics (such as LAB) help to create a more acidic environment, therefore making it more difficult for harmful bacteria to survive.

The other theory is a question of balance. A high level of probiotics means that space on the gut wall is made scarcer, as are nutrients, both of which again make life harder for the harmful bacteria. By tipping the balance in favour of ‘good bacteria’ you are making it more difficult for ‘bad bacteria’ to prosper, and therefore, to harm you.

It should be noted that the evidence for the health benefits of probiotics is strongest for digestive health.

For example, a study by Dr. Gerald Friedman of the Mount Sinai School of Medicine in New York found after a 28 day period of administering a multi-strain probiotic to 84 IBS patients, that daily occurrences of diarrhoea progressively reduced.

Another found probiotics to have a significant effect when administered with retrovirals in helping to reduce antibiotic associated diarrhoea in children. The study used a number of different strains and recommended further research into the most promising.

These are just two examples showing the promise of using probiotics to help treat (and possibly prevent) digestive health issues.

Where can I find probiotics?

Naturally the most well known source of probiotics is in yoghurts specifically marketed as having ‘active cultures’, particularly in breakfast yoghurts.

However, as anyone who has tried to find a non-probiotic yoghurt in recent years may have realised, probiotics occur naturally in many dairy products, including yoghurts. Those that have had probiotics artificially added will usually be labelled as containing ‘active culture’; otherwise they are probably referring to the natural probiotics present in yoghurt.

Aside from dairy, they can also be found in certain foods such as sauerkraut, some dark chocolate, microalgae, miso soup, pickles and tempeh (among others).

If you are lactose intolerant, simply don’t like any of the foods mentioned here, or don’t eat them regularly, probiotics are also available as dietary supplements. If you’re looking to get a particular health benefit for probiotics, be sure to research which strains are available in which supplements, and that are most appropriate for you, before taking.

If in doubt, always consult a doctor and/or qualified nutritionist.

Studies cited

http://www.sciencedaily.com/releases/2008/10/081006092656.htm

http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD004827.pub2/pdf/standard