Passports with extra pages belong to adventurous, fearless people. People who don't worry about getting typhoid or Japanese meningitis. Last week I took a bus across London and considered that intrepid. Even more so when I realised I hadn't washed my hands after touching the pole. Later, I spoke about the experience the way mountaineers talk about K2.

If anyone who knows me were to open my passport they'd think it was a fake. Myanmar, Israel, Budapest, Italy, Ireland, Nairobi, France? Somewhere between showering and sleeping, I've been around. Not that you'd know. When I think about the things I've done and the places I've been, I feel it should show more. There are people who I've met and just by looking at them I can tell - they've seen the world. When someone meets me, they seem shocked to discover that I've been anywhere other than to the doctor.

But I've always travelled a lot. When I was five I began going from New York to Bangkok every year to visit my father. Every summer I'd be put on the plane with a laminate ID. Like Paddington Bear. Travelling halfway around the world didn't seem a big deal then.

Now there are times when I have to remind myself: you've stayed on a tea farm in Kenya, you can handle going to a party in Brooklyn. So travel is useful. It reminds me that, no matter where in the world I might be, I'm still going to worry about the same things I worry about when I'm at home. As I write this, a text from a friend arrives: "Thanks for coming out last night."

What he means is: I'm surprised you left the flat. Another friend, who lives four miles away, has given up on my ever going to his house. He left a message telling me that a friend had a car and would be willing to give me a lift. I told him I'm not a fan of road trips.

I have a new paranoia. It began when I noticed that whole milk was being used in a skinny latte. I just happened to catch it and said: "Is that whole milk?" The woman pretended to have goofed but we both knew the truth: she hates people like me and whole milk is her revenge.

Now I've got into a pattern of not trusting the person who is making the latte and asking if they're using semi-skimmed milk in a suspicious tone. "You're sure?" I ask.

But because I don't want to seem like a fat-obsessed nuisance, I let them know it's the cholesterol and that I'm not allowed to drink whole milk on doctor's orders. Which isn't a lie but it's not as though I can produce a medical note. Even so, it doesn't make a difference. What are the chances that someone who I don't know and who I'll never see again is going to care about my cholesterol?

People talk about how travelling means leaving your comfort zone, but that's not necessarily true. It doesn't matter if I leave my house to go around the corner for a coffee, or around the world - it will always be a gamble