The flight from London to Bangkok took 11 hours and was rammed with sex tourists. We - my best friend and I - sat, our heads rigidly buried in spa brochures, while the sea of priapic men around us frothed at the mouth with thoughts of Thai girls.

There were men on their own and men in groups. Wide boys who didn't give a toss and men on whom cruel fate had decreed the kind of ogreish looks that mean a life of having to pay for it. As we came into land their excitement turned into a sort of rumbling. The greaseball sitting next to me downed his Jack D and Coke and leapt up. We could see him not very well hidden by the partition separating First class and Economy humming to himself in pale underwear as he removed his trousers to make way for a pair of loud Bermudas. My friend and I agreed that we found these men repulsive.

So we were pleased, on landing, when a member of the ground staff whisked us away from the mob in the direction of a propeller plane. Chiva Som is the world's most exclusive destination spa - to use the tourist vernacular - and arriving by private plane when we could have sat in the car for three hours seemed fittingly over-the-top. As we flew over the sparkling Gulf of Siam we imagined the sex-starved trogs queuing for buses below. We smiled knowingly then abandoned ourselves to thoughts of higher things: the holistic journey ahead.

Before we go on let's get one thing straight. Chiva Som isn't any old spa. Among the people who know about these things, it is the daddy of luxury health resorts, the my-body-is-my-temple paradigm to which every two-bit fitness centre with built-on Jacuzzi aspires. For years now Conde Nast Traveller, the expert on such matters, has ranked Chiva Som in its luxury Top Ten.

Even if you can't stand the things, you've got to give spas their due. In Britain the industry is worth £1.8 billion. Or rather a mere £1.8 billion. Britain is affluent and neurotic enough for the spa revolution to have taken root – we take more anti-depressants per head than anyone else in Europe, after all – but it is also too cold and too crowded.

Abroad is where the action is, where you’ll find a spa for every personality type (although not for every wallet): destination-, beach-, resort-, day-, gay-, hotel-, urban-, ski-, cruise-, airport-spas. There are even “spa lifestyle communities”, paradisical mini townships in which, if you are a Baby Boomer, you are going to retire. The reason I know this is because the people who do the meticulous research on these things told me. They spend a lot of time, these people, working out what you might spontaneously decide to do with your down-time in the future. Holistic technology is where luxury is going, I was told, the whole spirituality thing is getting a bit old.

Translated into English Chiva Som means Haven of Life. Of course it does. You can’t start a revolution in the travel industry if your name translates as Club Med or Mark Warner. Not any more. That was in the old days when Paradise was still a splashy palm-fringed and ocean-fronted affair, the odd speedboat or toxic rum punch thrown in for good measure: a paradise devised essentially for extroverts, and especially for men.

What does Paradise look like these days? It was hard to tell when we eventually rolled up at 7.30pm, in time for a succulent yet low-calorie supper but too late to see the place in all its sun-drenched glory.

It was too dark and we were too busy: a three-page health questionnaire to be filled out before morning plus a trawl through the 78-page Health and Wellness guide. Bent over the unfamiliar words I remembered for the first time in decades the feeling, aged 8, of cramming for the next day’s vocabulary test. What was Body Composition Analysis? How badly did we need Balneotherapy? Was life worth living without Functional Insight Training?

We had our pictures taken by the only non-banned camera on sight - the photographs are used as an aide-memoir for staff. An immaculate Thai woman explained over a glass of chilled lemongrass tea that the no-photography rule is there to protect the privacy of Chiva Som's celebrity guests. There would be no visual record of our stay save for the shot my friend later clandestinely took of me in a Nylon suit designed to help dissolve the cellulite around my “hip and thigh area” (my hips and thighs). But there would be celebrities. The immaculate Thai woman said something about the cleansing properties of lemon grass but we were no longer listening. It was our first night in the world’s most exclusive retreat and already we were engrossed in heavy visualisation exercises. We imagined tomorrow’s pool-side scene: the cast of Troy in pristine white towelling robes.

Brad Pitt wasn't there by the pool the next day nor did he ever materialise. Instead we found ourselves in the company of an assortment of very quiet people on sun-loungers, one or two of whom later turned out to be famous. With the exception of a model from Australia who made a production each morning of surging Venus-like from the pool, most of them were in their 40s and moved very little. Almost all of them were female. They lay very still in their sun loungers thoughtfully sipping coconut juice or staring out over the compound wall to sea. Sometimes they read. Often they read the Health & Wellness guide. Always they were very quiet. If you’ve ever been told off for splashing in the Ladies’ Pond on Hampstead Heath you’ll get the picture.

The model from Australia would have fitted right into Paradise circa 1985 but, frankly, she was out of place in the 2007 version. This was no place for a ravishing 23-year-old at her physical, mental and professional peak. Like any well-oiled business, Chiva Som has a house motto. Theirs is: “Balance, energy, health, perfection.” The problem with the girl was the fact that she was already obviously perfect. Ideally she would have waited a few years when perfection becomes technically impossible.

Retreat from what? What was everybody retreating from? In the impeccable Lotus flower-strewn sauna, steam-room and plunge pool we exchanged stories. Sindy was getting over the death of her husband. Barbara was getting over herself. Bob was getting over his wife who was still alive but, since he sold his film business for millions, was always there under his feet: he now spends three months a year retreating from his wife in a luxury spa. There was anxious Clive, big in the music industry, and Rosa who was just big. Rosa decided to go to a spa on the advice of her daughter, Clare, who shed two stone last year thanks to Chiva Som’s excellent weight management programme – the spa cuisine is legendary and the centre’s gym instructors are so knowledgeable that they are often poached by wealthy clients to work as personal trainers. The pressures of work in the intervening 12 months, however, had meant that Clare had put it all back on again, which was why she was here again this year, accompanying her mother. That’s the way it goes in the modern world. You advance in real life, then retreat to a spa. Retreating is not a positive thing to do in a battlefield but perhaps in the aftermath of a botched fitness regime or marriage gone wrong it is sensible.

At the beginning of every holiday comes a mandatory grey period in which you make the transition from your cynical every day self into the fey, gullible hippie you become after ten days of doing nothing. Our grey period had lasted two days in which time we spent a lot of time parodying the quotes on the multi-coloured complimentary book marks that had been lovingly placed on our bedside tables. They said things like "Dona, the Brahmin, was entrusted to distribute the Buddha's relics and ashes to various kingdoms which sent their messengers to ask for some portions," and we had no idea what they meant. We knew we’d entered phase two the day we found nothing wrong with a note that had appeared beside a complimentary piece of fruit. It said: “with its uniquely decorative bell-shaped appearance, the rose apple is admired as much for its appearance as it is for its flavour." Its Thai name, the note added, was Chom Poo. Etymologically, this was a big fat clue about what was involved in the search for perfection in a luxury spa.

It was followed by a second clue, in the form of another laminated note, propped up beside the jug of fresh Wheatgrass juice at breakfast the next day. "The health benefits of wheatgrass juice are endless,” it told us. “It has excellent detoxifying, cleansing, alkalizing, and deodorizing properties especially of the bowel and blood, absorbing waste products and encouraging excretion from the body." We took a slug each. Then we waited.

It may seem inconceivable to you now that within minutes of arriving in a top-notch spa you’d sell your own grandmother to encourage excretion, but it is so.

Within hours you are saying things like "seen any action today?", or, - more casual - after any period of unexplained absence, say, "any joy?". Perhaps you’ll slip into spa slang and call it, “detoxification” but in the end it’s the same thing.

How much, when, how often: these are the questions that begin to occupy your thoughts and conversation.

Chiva Som’s signature treatment is a deep stomach massage designed to release trapped emotions. It is one of the centre’s most popular treatments partly because it is a prelude to the king of all spa treatments, colonic hydrotherapy. We’d had fantastic thai massages, cleansing facials, soothing body wraps but these were small fry. Everybody else was having colonic hydrotherapy, not just once but two or three times a week.

Prodding around my stomach during my deep stomach massage a masseuse had an Indiana Jones moment, truly I thought she’d stumbled across some holistic treasure. She prodded some more before a delighted smile spread across her face. Confused, I wondered aloud whether she’d found a baby in there.

“No baby,” she laughed admonishingly. “I can feel your faeces.”

The masseuse packed me off for a colonic hydrotherapy saying something about removing the toxins from my liver and I was met by a nurse in a white smock who put on some soothing music. No need to be shy, she reassured me, hose in hand, Lady Diana was a fan and, besides, she added, “I love poo!”

The colonic hydrotherapy did me in. I couldn’t let nature take its course in the way the nurse wanted me to. I don’t know what it is but lying down to take a shit just goes against every one of the principles my mother had hardwired into me as a child. Eventually I limped off to bed. I lay there feeling a weight had been lifted off of me but not in a good way. I felt bereft. I actually started crying: this was the release of the complex emotional baggage everybody had been telling me about. I read the quote on my complementary book mark and felt comforted.

We left the Haven of Life the next day. We were sad to go. Real life seemed somehow too vivid in comparison, staff outnumber guests by 360 to 114 at Chiva Som and having to doing something, anything, for ourselves was a drag. There was disillusionment too. We noticed that not all Thai people were as delighted by our mere existence as the staff employed at the world’s leading holistic retreat; also that things called children existed (they are banned in Chiva Som) and that children care very little about your inner balance. In foul moods we made it to the airport and on to the plane. The first thing we saw on the plane were the sex tourists.

There they were, tanned and relaxed and healthier-looking - much, it had to be admitted, like we were. We’d drunk less beer and done more exercise but there were other irrefutable similarities. We had all spent the week paying a lot of money to be touched by people we had never met and we had all done this in modern approximations of mythical paradises - "Haven of Life" in our case , "Paradise-a-Go-Go" in theirs.

All of us had spent the week in pursuit of the perfect body. I knew what I thought places like Paradise-a-Go-Go said about the men who went there but I still didn't know what Haven of Life said about me, or the thousands of women who now spend their holidays flocking, alone or in groups, to spas like it. As I watched my tan flake off even on the plane I realised an important fact about paradise on this earth. We were all trogs really, destined, for the rest of the year, to remain outside the walled garden.

NEED TO KNOW

The tour operator Carrier offers five nights at Chiva-Som from £1,795 per person, based on two people sharing an Ocean View room. This price includes three meals a day, a daily 50-minute massage, daily fitness activities, return flights from London Heathrow to Bangkok with EVA Air, onward transfers to Chiva-Som. Price is valid until June 30. For information call Carrier on 0161-491 7630 or visit www.carrier.co.uk

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