Michael Wilson, Professor of Microbiology at University College London, said that the promotion of daily probiotics was devoid of robust scientific evidence that they improved health in any way. He added that while topping up on “good bacteria” might sound sensible for rebalancing or enhancing conditions in the human gut, it was based on “a lot of shaky understanding”.
“It’s all well and good saying that certain bacteria are good for you, but we don’t know about all the other species in the gut and how they all interact. We are basing a lot of probiotic understanding on shaky ground. You need to know you are using appropriate strains for appropriate conditions in appropriate people and we just don’t know those things.”
He said that there was some “instinctive sense” in thinking that manipulating the gut flora - or microbiota - might help with adverse events. But for people with compromised immune systems, increasing the bacterial load could risk problems such as septicaemia blood poisoning if there was a defect in the barrier in the gut separating bacteria from sterile tissue.
“No bacterium is totally innocuous. If you are healthy there is probably no harm in taking probiotics, but there is also no benefit. But to increase the bacterial burden if you are immuno-compromised is asking for trouble.”Prof Wilson added that the possibility of problems linked to probiotics would not be picked up because doctors rarely considered them as a cause.
Probiotics, the potentially beneficial bacteria and yeasts available as diet supplements and in some foods, may not be as helpful as widely believed. A new study suggests that under certain circumstances, they can be deadly.
This study, was the largest randomized, double-blinded trial of its kind, and the authors found no other reason for the harmful effects.
probiotic prophylaxis with this combination of probiotic strains did not reduce the risk of infectious complications and was associated with an increased risk of mortality
The "Seven Deadly Sins"
• Grains (wheat/rice/oats etc) . . . . . • Dairy (milk/yogurt/butter/cheese etc) . . . . .• Nightshades (peppers/tomato/eggplant etc)
• Tubers (potato/arrowroot etc) . . . • Modernly palatable (cashews/olives etc) . . . • Refined foods (salt/sugars etc )
• Legumes (soy/beans/peas etc)