Today Danone was forced to withdraw an advert for probiotic yoghurt because the scientific evidence didn't support it. The company claimed it boosted children's "defences" and cited various research studies to support it. The Advertising Standards Authority read the studies and found that although the studies were good, most of them weren't about the children in question, some of them used the wrong dosage of yoghurt or an inappropriate test group, and overall the results were inconsistent and didn't particularly support the claim.
I'm interested in this because probiotics is one of those weird new turns in commercialism in which you can't quite tell if there's real science there, or if there is nothing but an actor on screen grinning and rubbing her belly, saying "I trust good bacteria" over and over again.
I've heard some scientists saying that probiotics have been shown to be good for ill people recovering in hospital (whose natural gut flora might need "topping up") but that the evidence isn't there yet for any point at all in healthy people gulping down these yoghurts once a day as if they were your daily medication.
There are moves afoot in the EU which sound to me like a good idea. In 2006 a new EU law came in, stipulating that all medical-sounding marketing claims must be verified, and they now have a committee which looks at the evidence and pronounces yes or no on them. The claims for various yoghurt drinks, as well as all kinds of other products, has been submitted to this committee. They made the judgment that general probiotic claims aren't supported by evidence, although they'll be looking at more specific manufacturers' claims later.
The change hasn't actually come into force yet, but when it does, hopefully it won't be down to us to peer at the TV advert and think to ourselves, "Is that science or is that bullshit?" - it's only reasonable that we shouldn't have to do that, and companies should have to prove their stuff works before they parade it around in scientific clothing.