By PETA BEE
WITH their promise to rid the body of the ‘bad bacteria’ that make us ill, it’s no wonder so many of us are buying probiotic dietary supplements.
Two million Britons now regularly consume these ‘friendly’ bacteria in the form of drinks, yoghurts, powders and capsules.
‘Friendly bacteria’ sound so harmless. So what then are we to make of the story last week that patients with pancreatic disease had died as a result of being given them? Doctors at the University Medical Centre in Utrecht, Holland, reported that 24 out of 296 patients died during a study to find out whether friendly bacteria known as probiotics affected inflammation of the pancreas.
The researchers said their results were proof that ‘extremely ill’ people should avoid probiotics, and the Dutch Food and Consumer Product Safety Authority has ruled that supplements should not be given to patients in intensive care, those with organ failure or anyone being fed through a drip. So should we be concerned about the new findings? In fact, when it comes to seriously ill patients, many UK hospitals already follow the approach being adopted by the Dutch, says probiotics, are treated as hostile Catherine Collins, chief dietician at St George’s Hospital in London.
In unhealthy people with weakened immunity the so-called friendly bacteria, such as lactobacillus casei or bifidobacteria, which make up probiotics, are treated as hostile invaders.
‘In some cases they can induce a potentially fatal condition called lactobacillus septicaemia,’ says Collins. ‘We’ve treated two cases recently at St George’s.
‘A lot of hospitals don’t embrace probiotics because the living bugs they contain have the potential to cause infection in vulnerable people.’ But what does this mean for the rest of us? Probiotic products aren’t dangerous for healthy people, says Claire Williamson, a nutrition scientist with the British Nutrition Foundation, but adds that manufacturers are often guilty of exaggerating their benefits.
PROBIOTICS are a relatively recent ‘invention’. Russian Nobel Prize winner and father of modern immunology Elie Metchnikoff was the first to discover beneficial bacteria at the beginning of the 20th-century.
He made his discovery after observing how Bulgarian peasants who consumed milk products containing fermenting bacteria appeared to enjoy extraordinary longevity and good health.
It’s now generally accepted that the human gut contains different strains of bacteria, some of which are beneficial, some that help with food digestion and some that are disease – causing.
But do supplements help maintain the ‘healthy’ balance of these bacteria, as proponents of probiotics suggest? Earlier this month, Professor Jeremy Nicholson, chair in biological chemistry at Imperial College London, revealed that lactobacillus probiotics seem to enhance digestion and may even assist weight loss by preventing the body from absorbing fat in food.
But Nicholson and his team were not sure how or why they work and say that, because the studies involved mice not humans, more investigations need to be carried out.
‘They can have an effect but we are still trying to understand what the changes might BLURRED headache eye to SITTING your of Interlace your your hands light eyes mean in terms of overall health,’ he says.
‘We have established that introducing friendly bacteria can change the dynamics of the population of microbes in the gut and could reduce the amount of fat digested by the body, but more work is needed in this area.’
Claire Williamson says: ‘There is some evidence that probiotics can help to stabilise gut flora that is disrupted when people take antibiotics, and also that the supplements can reduce symptoms of IBS.
‘But as yet the findings are inconclusive and should be treated with some caution.’ Critics doubt whether probiotic bacteria survive transit through the gut and suggest they are likely to be killed by acid in the stomach.
They also argue that a pot of probiotic yoghurt containing 1- 5million bacteria is unlikely to have any impact on the 100 trillion bacteria in gut microflora.
Indeed when Glenn Gibson, professor of microbiology at the University of Reading, analysed a range of probiotics on sale in the UK in 2006, he found up to half of them were useless and some contained types of bacteria that rendered them potentially harmful.
‘Around half the products don’t match up to what their label says and have either the wrong bacteria or the wrong numbers,’ he said.
However, better-known brands such as Actimel and Yakult were found by Gibson to contain at least tenmillion friendly bacteria from the lactobacillus or bifidobacteria families, which means they might be effective in aiding digestion.
Another pointer for the types of products to look for came from an earlier study Gibson conducted for the Food Standards Agency.
This showed that products containing high levels (ten million to several billion) of bifidobacterium and enterococcus faecium had the best survival rates in the upper intestine and that lactobacillus bacteria survived for up to five days in the lower intestine.
Drinks containing lactose or oligosaccharides (such as Yakult) or supplements that were enteric-coated so don’t dissolve until they reach the intestine (Multibionta) have the best survival rates. HOWEVER, Gibson’s tests showed that even if they did survive, probiotics did not necessarily lead to a beneficial increase in friendly gut flora. In other words, to some people they may be useless.
Furthermore, many nutritionists, such as Sue Baic, a spokeswoman for the British Dietetic Association, believe a better way to promote natural good gut bacteria is to consume prebiotics substances that support existing gut bacteria.
Found in human breast milk, prebiotics contain oligosaccharides, a type of carbohydrate that only our guts can feed upon and which are necessary for friendly gym necessary for friendly bacteria to multiply and flourish.
‘There are dietary sources such as onions, garlic, chicory and banana,’ she says.
‘But because we don’t eat enough of these, a supplement such as fructooligosaccharide may help friendly bacteria to grow in the gut.’
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