The use of probiotics has become a common concept amongst health conscious individuals. However, most general knowledge goes little further than vague notions of ‘good bacteria’ and ‘healthy tummies’. The idea that probiotics are useful for general good health, and particularly digestive health, has become widespread, but often with very little understanding of how or why.
For the curious, here is a quick guide to probiotics – what they are, how they work and how well they work.
What are probiotics?
The official World Health Organisation (WHO) definition states that probiotics are “live microorganisms which when administered in adequate amounts confer health benefit on the host”.
This is a fairly wide reaching definition and refers to a staggeringly large number of microorganism types. However, for the purposes of probiotic added food and supplements, the two most common forms of probiotic are Lacti acid bacteria (LAB) and Bifidobacteria.
Many of these microorganisms are already present within our body but often in less than optimal amounts.
How do probiotics work?
As may be expected, exactly what effect probiotics may have is dependant on what strain of bacteria is under the microscope. However, there are a few (very) general observations that have been made about how probiotics may be beneficial to our health.
The broadest is a simple ‘good vs bad’ bacteria balance in our gut flora. The idea being that by tipping the balance in favour of ‘good’ bacteria the ‘bad’ bacteria that may give us diarrhoea and other digestive upsets is starved of nutrients and/or space on the gut wall.
Some probiotics may also help to amplify the effects of pre-existing healthy bacteria in the gut and may even aid production of infection fighting white blood cells.
Finally, there is some evidence that probiotics may produce lactic acid, making life more difficult for harmful, pathogenic bacteria that prefers a more alkaline environment.
How effective are probiotics?
Research into the effectiveness of probiotics is still in its relative infancy, but there have been some very encouraging studies.
Most notably, probiotics have been found to reduce bloating in IBS patients, reduce antibiotic associated diarrhoea and have a positive effect when administered in conjunction with vaccines against rotavirus infection.
There is also evidence that probiotics may help to treat yeast infections such as candida.
Again though, it is important to note that the effectiveness of probiotics is dependant on both the strain of probiotics ingested, and the dosage, just as with any supplement. As such, if you wish to derive a particular health benefit from them, you may be better taking a specialist supplement rather than relying on mass-market foodstuffs. Consult a doctor or nutritionist if in doubt.