It’s easy to understand why Thailand’s called the Land of Smiles. A disarming array of smiles is on offer there.

Outside a Bangkok shopping centre a security guard lit up the whole place with his grin when he clicked his heels and saluted every time we walked past. Calculated tooth bearing by some street hawkers, however, wasn’t so heart warming.

But who was it who said the act of moving the facial muscles that create a smile actually releases chemicals to raise spirits and boost the immune system anyway?

After a while I stopped worrying whether the smiles were genuine or fake. Returning the compliment felt unnatural to begin with. People from our part of the world smile so seldom it’s like roller skating. We know we could do it when we were kids but it takes a while to get the skill back.

On the island of Koh Samui off the Southern Coast of Thailand my husband found it very easy to smile when a restaurant dinner for three, including beer, cost around $20.

He couldn’t believe his luck when our daughter and I went on a shopping spree (two words that usually paralyse him with fear) to buy two pairs of fishermen’s pants, one 30% silk pashmina and two sparkly scarves for about $28.

Koh Samui is designed to make fathers smile when a one hour Thai massage costs around $7. For that price he cheerfully booked all three of us in. We lay fully clothed on adjacent mattresses while laughing tribeswomen ironed every kink out of our puffy Western bodies.

I smiled a lot, too, apart from the day spent inspecting the inside of the hotel room toilet bowl. I’m not going into it in detail because there’s nothing duller than people droning on about their health (except when they insist you study their 100 holiday snapshots –incidentally, I have 125 and you’re welcome to pop over and see them).

Anyway there’s plenty of time to think when you’re feeling crook. I worked out it wasn’t one of the street food stalls that had declared war on my stomach but a pastry snack from one of the hotel’s warming ovens.

A couple of days later I felt perfectly normal, possibly two kilos lighter and finally adjusted to the heat. In hot countries I always take interest in what the locals wear. They’ve invariably worked out the best gear to survive the climate.

Fisherman’s pants are perfect for Thailand. Not only are they cool and comfortable, their wide legs draping from the waist flatter matronly, Antipodean figures.

Made from a single piece of lightweight material, fisherman’s pants could be mistaken for enormous nappies. Like nappies, they take practice and skill to put together.

Draping the new fisherman’s pants around the lower part of my body, the way the shop assistant had demonstrated, it was unnerving to think my dignity depended on two hand tied knots – one at the front of my waist, the other at the back. I never was much good at tying things.

My husband was made to swear on pain of being force fed hotel pastries that he’d alert me if the fisherman’s pants showed any sign of causing public humiliation.

Modesty’s huge in Thailand. Visiting the Grand Palace in Bangkok we’d been inspected by guards to make sure our arms, legs and feet were suitably covered. I didn’t want to show a centimeter more flesh than was polite.

Feeling almost as native as the locals in my pants, I climbed aboard a taxi truck with husband and daughter for a night on the town.

With his unerring sense of style my husband found a shop selling men’s designer clothes that apparently weren’t fake at half the price they’d be back home. It was air conditioned and the staff were quite snobby but they still managed to smile a lot.

I took charge, whisking shorts and shirts off the racks for him to try. It was hard to know why the shop girl was so amused by my behaviour. I wasn’t doing anything unusual. Perhaps Thai men do all their own shopping. Whatever, she laughed uncontrollably at my pathetic jokes and he walked out with a fine new pair of shorts.

It wasn’t till we climbed back on a taxi truck that I realised my fisherman’s pants had come undone at the back, revealing far more than anyone from any culture would ever want to see.

No wonder Thailand had become The Land of Giggles.