Probiotics: what are the health benefits?

Probiotics: what exactly are they?

The WHO (World Health Organisation) clearly defines probiotics as foods or supplements that “contain live microorganisms which, when ingested in sufficient amounts, confer a health benefit on the host”. How do they do this? Probiotics, which are actually bacteria or yeasts, encourage a healthy balance in our gut flora. The many studies conducted on the subject have clearly identified gut microbiota (which contain some 100 billion bacteria) as playing a crucial role not only in our digestive systems but in our health as a whole.

Probiotics/prebiotics: what are the differences?

Probiotics are bacteria and yeasts which nourish and stabilise gut flora, while prebiotics can be considered probiotic performance-boosters – they increase their activity. A kind of ‘fertiliser’, prebiotics are found primarily in inulin and fibre (particularly fructans). The symbiotic combination of probiotics with prebiotics thus leads to improved efficacy and increased health benefits.

What are the various strains of probiotics?

There are many strains of probiotics, each with different compositions and offering different health benefits. One probiotic may stimulate intestinal transit while another improves lactose tolerance, etc. The best-known strains are Lactobacillus, Bifidobacterium, Streptococcus and Saccharomyces, found in fermented products, but there are many more. These strains are themselves sub-divided into several categories. There are thus multiple possible combinations and benefits to health.

What health benefits have been established for probiotics?

The many scientific studies conducted in this field over recent years have confirmed probiotics as an indisputable aid to human health, with one of the most-discussed areas of study being intestinal transit problems. This is significant given that poor digestion is a common complaint among Western societies. Probiotics have proven efficacy in this area: demonstrated health benefits include improved transit and tolerance to lactose, accelerated recovery from diarrhoea and gastroenteritis and decreased IBS symptoms.

Other promising research

Studies have also highlighted probiotics’ broader potential for supporting human health. It seems they may boost the immune system and protect against serious diseases such as colon cancer; they may also have a preventive effect against eczema and a curative one in fungal infections (particularly vaginal mycosis). All these findings need corroboration by future studies, but given the proven virtues of these bacteria, it seems likely that other, as yet unknown, health benefits will emerge.

Where are probiotics found?

Probiotics are naturally present in fermented products such as yoghurt, kefir, and sauerkraut, as well as in olives and brewer’s yeast. Consuming a diet rich in probiotics (combined with prebiotics whenever possible) is thus one way of benefiting from these substances’ properties. But supplementation also offers important advantages here, for two main reasons: the benefits gained from the combined effects of different strains of bacteria/yeasts, and the fact that the probiotics go directly to the gut. Why so? It’s thought that up to 90% of probiotics – which are only properly effective when they reach the gut, and more specifically the colon - may be destroyed by acidity in the stomach. Capsules avoid this problem because they dissolve only when they arrive in the gut, and can be used as a treatment – an additional advantage since in order to be effective, probiotics need to be taken every day on a sustained basis.