In a healthy gut, there is a balance between beneficial and pathogenic or “bad” bacteria. Climate, ageing, food, stress, illness or infection and medications can disrupt this balance leading to an excess of “bad” bacteria leading to bloating, gas and constipation. While individual studies and anecdotal evidence suggest a wide range of uses, well-studied and accepted uses for probiotics are much fewer.
Probiotics may help prevent traveller’s diarrhoea and diarrhoea caused by antibiotics, and are used in the treatment of acute infectious diarrhoea. The lactobacillus rhamnosus GG and saccharomyces boulardii strains have been shown to be most effective for these conditions, but there are no formal clinical guidelines for probiotic use. Accredited practising dietitian Milena Katz says that a person’s gut bacteria are very individual – like a finger print - so there is no blanket advice. Katz says it’s a case of trial and error and advises patients with gut problems to try high strength probiotic capsules over six weeks to see if symptoms improve.
For healthy people, probiotics aren’t necessary, but Katz says eating probiotic foods like yoghurt aren’t going to hurt and are generally well tolerated. Probiotics are not advised for people with severe illnesses or who are immunocompromised.
When CHOICE asked people about probiotic use, positive messages abounded: “Yakult, every day. No ill effects. Actually think they are part of me beating Crohns”. Another said he used kefir (an eastern European probiotic drink) and “never had any ill effects, just the opposite in fact!”. One fan of Inner Health Plus wrote: “It helps my partner who suffers with MS and often has problems with candida (a yeast) overload in his throat and a bloated tum”, while another commented: “I also have an irritable bowel and a bloated tummy at the best of times... It helps but has not solved the problem completely”.
Bugs for babies
Strains of bifidobacteria and lactobacilli – along with other lactic acid bacteria - are found naturally in breast milk and thought to contribute to normal gut development and function. In newborns, bifidobacteria make up 95% of the gut’s microbial population but this decreases to 25% in adults.
Manufacturers such as Nutricia, which makes Aptamil (formerly Karicare) infant and toddler formulas, are adding prebiotics to their products. Listed as galacto-oligosaccharides (GOS) and long chain polyfructose, Nutricia says these are “similar in form and function to the prebiotics found in breast milk” and “encourage the good bacteria in the digestive system to flourish, reducing the amount of harmful bacteria” and “assist in digestion and promote softer stools”.
A recent report by the American Academy of Pediatrics says there may be some long-term benefit of prebiotics [such as oligosaccharides] for the prevention of atopic eczema and common infections in healthy infants, and while adding probiotics to infant formulas wasn't shown to be harmful to healthy infants, more evidence is needed to support routine use.