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Tuesday, January 29, 2008

Can Friendly Bacteria Be Dangerous?

Can so-called "friendly" bacteria, the type that are added to "functional foods" and known as probiotics, be dangerous? (See my Primer on Probiotics for an introduction to the subject.)

Questions like this make me grumpy. The answer is that anything can be dangerous. Water can be dangerous, even plain, ordinary, non-contaminated water. The question is a bad one.

Here's the correct question: Is the so-called "friendly" bacteria added to products likely to be dangerous to you? And that answer, of course, is no.

Let's take a peek behind the dumb, over-broad question and get to the meat of the issue, taken from an article by Peta Bee in England's Daily Mail.

The bad news is that people who are seriously ill, especially those suffering from inflammation of the pancreas, should not be given probiotics. Doing so occasionally "can induce a potentially fatal condition called lactobacillus septicaemia." Hospitals already know this, however. Probiotics are already prohibited for most such patients. 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."

Dangerous? Yes. Something you or I have to worry about? No.

I'd worry more about the rest of the article, which says that most probiotic products don't contain enough of the bacteria to be helpful. Not helpful is not at all the same as harmful, to be sure, but you're probably paying extra for the word "healthy" to be slapped on the label.

I'm not convinced there is enough good science cited in the article to judge the probiotic beverages and foods on the market. Most people probably don't need to pay for probiotics when a container of ordinary yogurt may give as much benefit, though. I've said as much before, as in my posting Answers on Probiotics.

It's an issue I'll keep an eye on in the future.

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1 comment:

Martin Johns said...

Apparently, at least one probiotic is a prescription only product, so someone believes they are dangerous. Seems ludicrous though.

There are lots of those products on the market. is a great place to get ratings on the various brands.