Tim Spector

That's probably why we've got so many allergies now that we didn't have 40, 50 years ago because breastfeeding rates have gone down and diversity of baby foods has gone right down.

They're now getting ultra processed foods very early on in life.

And you combine that with cesarean sections.

Right.

plus antibiotics, it's a recipe for all these allergies we're getting, isn't it?

Because as you said, a badly trained immune system that our ancestors didn't have.

They had the perfect system to train it.

Can you tell us a little bit about that and sort of sneak peek?

Yes.

Well, now the ZOE database of all the members who've given their microbiomes is over hundreds of thousands of individuals.

And many of these we've linked to their diet and these other factors.

And so we've put a lot of this together to work out new ways of scoring.

What is good and bad bugs?

Because up to now, we've just used this, what's called diversity, which is the number of different microbes, which I think Susanna agrees is a rather crude tool that doesn't really sort of help in a number of situations because you get good and bad ones lumped together.

And what we've found is by getting all these outcomes, including things like visceral fat and body mass index and heart problems and blood cholesterol and blood pressure and

everything bad about you, link that to foods that are associated with that and link to microbes that are also associated.

We've come up with this cool way of finding what are the good and bad microbes that predict these outcomes.

So this is a paper that's coming, but that first paper is mainly to give us a new way of looking at gut health.

through these really big, massive samples that finally are going to tell people how they can assess their own gut health compared to others in a way that doesn't get messed up like it used to in the past by...

You can have lots of inflammatory microbes and you have a good diversity, but that doesn't mean you're healthy.