Hello, I'm Greg Jenna and good news, Your Dead to Me is back for a new series. Here we go. Yes, we'll explore Emperor Nero's notorious reign with Professor Marybeard and Patton Oswald. I would not want my daughter having the remote control, not alone an empire. We'll dissect the decadent life of Philippe Duke-Dor-Leon with Tom Allen. I've often tried to pretend I'm an aristocrat and being very quickly knocked down. And there'll be so much more with comedians like Olga Koch, Mike Mosniak and Rihalina. I'm excited. You're dead to me. The comedy podcast that takes history seriously. Listen first on BBC Sounds. Welcome to our podcast coming up. we've got an item on ageing and the immune system, why we're having to change the type of flu jab given in the UK to older people. We're also looking at cannabis. Margaret McCartney is with me. Margaret, have you been worried by the way that cannabis is portrayed in the media? It's often seen as this sort of wonder drug that none of us are allowed to have.

I know. I think what really upsets me most is that cannabis has not been treated as a compound

worthy of scientific investigation and somehow it's got caught up in a sort of hype about

either believing it's just far better than it actually is or alternatively people sort of

writing it off and sort of saying, oh, that's just for hippies, you know, and the truth is somewhere in the middle. But even researchers treat it with a wry smile, looking at some of the titles of the papers. Yes. Yes, there's all these papers in the scientific literature, you know, seeing through the haze, seeing through the smoke of cannabis. You know, come on, can we not just have a proper sciencey discussion about this without the silly jokes?

Well that's exactly what we're going to try and do

this programme. Maybe I'm just being very grumpy, Mark.

This is the BBC.

Coming up in the next half hour,

ageing and immunity,

why a better understanding

of how our defence is weak

and as we get older

is influencing flu vaccines

for the next season. The flu virus is constantly changing and it changes the proteins

on the cell surface. So what the World Health Organisation tries to do is it tries to guess

what flu is going to be present in the next winter season. But that's a challenge, isn't it, for every age group?

For every age group, yeah.

What is it specifically about the over 65s that present such a challenge?

Now, unfortunately, as we get older, our immune system doesn't work as well.

So when we inject the flu vaccine into older people,

unfortunately, it's just not generating an appropriate immune response. And so in older people,

...