A medical researcher says that we've gone too far with cleanliness and it's having negative health effects on our children.
Mike Berridge proposes in his new book, The Edge of Life, that we should expose our kids to more bacteria. But are parents getting the message?
Bronwyn Morrison is not the type of mum to follow her two children around with antibacterial wipes.
"We're pretty relaxed about it in our household," she says.
She jokes that makes her sound like a bad parent, but Professor Berridge told The Nation she's got the right approach.
"We need to be exposed to our environment," he says. "You might think of it very much as a vaccination, as a tolerisation to our environment."
It's called the Hygiene Hypothesis – that by keeping bacteria away from babies, we're lowering their immunity.
Prof Berridge says there's scientific proof that's causing higher rates of asthma and allergies.
"If you raise, for example, a mouse in a sterile environment, that mouse has enormous problems. It just will not survive."
Prof Berridge says TV adverts promoting numerous sprays and wipes drive a lot of these issues. The very products promising to keep your child healthy could be doing the opposite if they're used too often.
Allergy New Zealand says children should be allowed to get a bit dirty and also try different foods at a young age. Doing so could protect them against allergies, which experts say are at epidemic levels in New Zealand and getting worse.
Ms Morrison's youngest child, Jackson, turns two next month. He's already got a touch of eczema and asthma.
She says conflicting messages about what children should and shouldn't do are confusing.
"I think it can be quite stressful. I think you've got to do the right thing by your kids and make up your own mind really."