I don't know what I expected to happen while I was in Thailand on my gap year, apart from some kind of weight loss from dysentery. The year didn't start well: I'd suffered from anorexia during sixth form and my recovery had included a humiliating cycle of bingeing and starving.

By the time I arrived in Thailand in February of this year, the bingeing had won out and I was heavier than I had ever been. Aged 18, I covered up in frumpy kaftans, feeling fat and middle-aged. My hope was that I would get a nice tan and return home triumphant, skinny, gorgeous and happy.

In reality, I found myself with no money, no friends and a large dose of homesickness, and ended up staying in a Buddhist monastery in Bangkok for six weeks. I lived with the monks, meditating for eight hours a day. And, to my surprise, this turned out to be the best thing that had ever happened to me.

I had planned to work at a children's charity in Pattaya, in eastern Thailand, for six weeks. But I hated this notorious sex town, and the balding, fat, sweaty men going with tiny Thai girls (and boys) in hotpants. The charity didn't turn out as I expected: I thought there'd be lots for me to do and lots of other young people to make friends with. In fact, I was excruciatingly lonely. Terrified of this vast, noisy country, still hating myself, I just wanted to go home.

Strange turn of events

Less than two weeks into my stay I was robbed of all my money, including £400 cash and almost £1,000 from my bank card, which I had stupidly left in my guesthouse room. Distraught, I used my last bit of cash to buy a bus ticket to Bangkok, and spent the entire journey wailing into the bosom of a wonderful Thai woman. On arrival in Bangkok, she bought me a McDonald's and gave me some money. Then she headed me in the direction of the monastery, where I could stay free, after I had mumbled something about “meditation” and “Buddhism” and “spiritual enlightenment”.

Several hours later, I was speaking to an old, cross-looking monk, asking sheepishly whether I could spend a few nights there, and feeling a fraud as I explained my lifelong fascination with Buddhism and my desire to improve my meditation. After a long and bemusing conversation about the “Eprisets” (the Eight Precepts of Buddhism, as they turned out to be), he said I could stay, but that I'd have to “work very hard”. He showed me to my floor space in one of the sleeping rooms, which I shared with up to six Thai women. I spent the night wishing I was home watching Midsomer Murders.

The next few days passed frustratingly slowly. We awoke at 5am and prepared breakfast - usually a selection of fish, rice porridge, vegetables and fruit - which we presented to the monks before eating ourselves at about 6am. At 7am I went to my meditation room, and there I would sit cross-legged, watching my breath coming in and going out, and concentrating on the present moment. This is pretty hard, especially when all I wanted to do was think of my sorry situation. Mid-morning lunch was followed by more meditation, and then a two-hour break, during which I either cried or rang my mother, or both, sitting on the front steps with a cup of tamarind-leaf tea and watching the big brown dogs that lazed about in the sun all day, waiting to be kicked by the passing monks.

One monk told me that the dogs were the reincarnation of monks who had been bad in their past lives - proved by the fact that their coats were the same colour as the monk's robes - and deserved to be kicked.

Living in the monastery meant I had to follow the precepts: no eating after noon; no touching the opposite sex (even talking to boys was tut-tutted by the older nuns); no music, reading or TV. I wasn't even supposed to write, but needing some form of escape, I kept a diary. Later, I interviewed the “cross” monk in the evenings about his extraordinary life. He turned out to be the kindest man, and insisted that I called him Luang Pho, or Grandpa. We grew very fond of each other and every day he would give me little presents - ice-cream and soy milk, usually, but also mountains of Buddhist books, which he inscribed to his “Dear Daughter”.

To my surprise, I began to enjoy my meditation. My mother (who is always right) has been meditating every morning for more than ten years and is often telling me and anyone else who will listen about the benefits she has encountered: understanding relationships better; an increased sense of wellbeing; stronger self-esteem. When I would complain about feeling depressed, fat, or confused, she would tell me to spend 20 minutes sitting in the garden, “listening to my body”. Usually I would forget and continue to feel grumpy for the next few days, or I would reluctantly sit on the lawn and feel self-conscious as I waited for the alarm clock to release me from my ten minutes of navel-gazing. I was sure meditation wasn't going to help me.

My problems were different; they couldn't be fixed by simply sitting still every day. I needed intervention! A personal trainer! Oprah Winfrey! A hypnotherapist! But in the monastery, with no other option but to sit and at least try to meditate, I slowly found that I could sit for longer and longer, sometimes more than an hour. And I began to feel clean and refreshed afterwards, as if I had bathed in a cool sea.

I started to feel proud of myself

My memory became sharp, and I could remember my chants, which impressed my old monk no end. I gradually stopped being angry with myself and starting feeling proud of myself. I saw strengths that I had never noticed before, and I stopped punishing myself with food and lost the extra weight naturally. I've never really been religious, and I was not attracted to Buddhism as a faith, but I felt that meditation allowed me to understand myself better and to find the right thing to do. Essentially, it taught me to listen to myself.

Since I returned from Thailand I've been living and working in London. Life is fun and exciting (mostly) and always busy. But somehow, between the traffic and the parties and running for the bus, I've managed to keep meditating. I don't practise every day, but I try to find time because it boosts my self-esteem and when I have a problem, it helps me to deal with it

MEDITATION INSIGHTS

What is it? Vipassana (meaning “to see things as they really are”) is a form of meditation that focuses on breathing. Buddhists believe that practising this regularly can lead to greater spiritual insight.

What's the evidence? A 2006 review examined 67 studies of brain activity during meditation. The scientists found that the nervous system is affected by meditation, and that it might help people to have more balanced emotional responses to stress.

Learn it here The Good Retreat Guide, by Stafford Whiteaker (Rider & Co,£12.99) contains information about where to learn Vipassana and many other styles of meditation. To find out more about ten-day Vipassana retreats of “Noble Silence”, consult www.dhamma.org

HARRIET ADDISON

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