Take Natalie, a 31-year-old solicitor living in west London, who was told by doctors two years ago that she suffered from Irritable Bowel Syndrome (IBS). If she eats too much dairy produce her abdomen bloats to twice its size and the pain that accompanies it is, she says, excruciating. Her shelves are crammed with self-help books. Indeed, all other topics pale into insignificance when the subject of her bowels and dietary needs is discussed, which is frequently.
Since Natalie began a food-combining diet, she has planned every meal with military precision. Foods containing starch, protein and alkalis are eaten separately, so that they are more easily digested. She feels conventional medicine has failed her, and has turned instead to alternative remedies, everything from aromatherapy to detox diets, acupuncture and even colonic irrigation.
None has had any long-term effect, and she is still looking for a solution to her problems. One of her few comforts is to share her experience with a group of female friends who also suffer from the condition. "I can't believe how many other women I speak to experience this," she says. "At least now I know other people are feeling the same way."
IBS affects an estimated 12 million people in the UK; its cause is still unknown. According to Glyn Hudson, a counselling psychologist in general practice in Bristol, 9 times out of 10 the cause is stress. "It's psychosomatic. For some reason, they can't express their emotions, and so it comes out in a physical way," she says. "It's like a 20th-century plague, and there has been a massive increase in it." Dr Hudson's patients receive "stress management training", which combines emotional counselling with advice on how to improve diet and exercise. "Rather than deal with the symptoms, it's important to look at why you got it in the first place," she explains.
It seems that many of today's sufferers are doing both. And it's not just those diagnosed with IBS that take such a keen interest in the day- to-day operation of their bodily functions. We live in a time when the benefits of spring-cleaning our insides fill pages of newspapers and magazines.
Readers are instructed to consume bucket-loads of raw fruit, vegetables, and undressed salads washed down with herb tea or tepid mineral water, flavoured perhaps with a single slice of lemon. It's difficult to make this kind of regime sound attractive. Last month the Daily Mail 24-hour "spring-clean" detox diet did its best with such enthusiastic tips as: "Frozen grapes taste wonderful as the pulp turns to mash"; "slice or cube fruit before eating for a more interesting texture"; and don't let starvation get you down, why not "pamper yourself with a face mask"? Internal cleanliness has taken its place next to godliness.
This is certainly the ethos at London's Hale Clinic, which is said to count the Princess of Wales among its clients, and offers 30-45 minutes of colon hydrotherapy for pounds 60. Outlined in the clinic's pamphlet as a "gentle infusion of warm, purified water that can help eliminate mucus, stored waste matter and toxins from the bowel", the process sounds positively sordid, despite the anodyne description: "Water will be gently introduced into the colon via the rectum whilst the therapist uses special massage techniques to stimulate the release of stored matter. Your modesty is preserved at all times," the blurb promises.
Katherine Monbiot, one of the clinic's hydrotherapists and chairwoman of the Colonic International Association, treats an increasing amount of clients who are what she terms, "vertically sick". "A lot of people aren't ill enough to lie down but they're not just not feeling well either," she says. "I see an awful lot of clients who are suffering from living in London. Poor diet, pollution and stress all take their toll. You have to take off that toxic load."
Not everyone is convinced by such a view. Vincent Marks, professor of clinical biochemistry at Surrey University, is an outspoken critic of colonic irrigation who argues that the process interferes with the lining of the colon and its natural functioning.
"The body is brilliant at turning the most poisonous substances into innocuous ones, without any outside interference," he says. "With this practice, you are almost certainly doing yourself more harm than good." This does not seem to deter the hundreds of clients who willingly part with their money for a weekly flush.
According to Professor Marks, the human body is well able to cope with almost anything, if left alone to get on with it. "Our bodies have got a remarkable number of detoxification mechanisms anyway. The colon does an extremely good job," he says. In contrast, the plethora of health clinics tend to promote the opposite view: that it takes external expertise to guarantee internal well-being and that ultimately our insides cannot be trusted to function by themselves.
Health pundits would also have us believe that most of the things we put in our mouths are doing us no good. Apart from the artificial colourings, taste enhancers, preservatives, detergents, insecticides and herbicides that threaten our internal status quo, food intolerances are increasingly becoming the affliction of the moment.
The latest high-profile intolerance is sensitivity to dairy products - lactose intolerance. The condition is already well-documented in the US, although it remains controversial; one American medical journal claims that most sufferers' symptoms are greatly exaggerated. People with lactose intolerance are unable to eat dairy products, because they experience painful cramps and bloating, supposedly caused by a low level of lactase, the enzyme within the lining of the small intestine which digests milk.
It seems that we are now in a situation where every type of food can be viewed as a potential enemy; small wonder the detox industry is flourishing. You don't even have to starve at home; for a fat fee, someone else will prepare the herb tea and grate the raw carrot. Around the country, elegant country mansions have been transformed into ascetic retreats. Flushing out the system with hot water and vegetable juice does not come cheap, though.
Stop the World, based in Somerset, describes itself as "a haven of nurturing countryside". Kate Rutterford, 36, stayed there recently, paying pounds 875 for a rigorous six-day detox which included consultation, exercise classes and massage.
She endured a strict diet of fruit, soup, and raw salads, as well as a liver flush (fruit juice and oil). "There were lots of reactions I hadn't anticipated. One morning I just couldn't stop crying - I felt as if I had no control over it." She was encouraged to let her emotions out and "allow it to happen". By the end of the week her hunger had subsided and she fulfilled her objective of losing weight. "I started to feel quite light and actually clean inside, as though my system had been fluffed up."
Such regimes form part of an expanding and highly profitable service industry. Its success may be because, unlike conventional science, holistic alternatives promise us instant benefits.
Medical opinion remains sceptical. "It's a complete lack of understanding about biology, it's a prostitution of science," says Professor Marks. "The idea that certain foods are full of toxins is wrong. Nearly everything has natural toxicants in it, and our bodies are constructed to turn those materials into harmless compounds. People want to believe there's a nice simple explanation for everything - for example, the colon is a cesspit, therefore clean it out. But things are, of course, far more complicated than that."
According to Colin Samson, a lecturer in medical sociology at Essex University, the current obsession with our bodies reflects the modern Zeitgeist: self- absorption. "I think it's partly due to the cultural change that occurred in the 1980s, where the emphasis was on doing things for oneself rather than for others," he says "We're seeing an extension of those ideas in the Nineties. Before Thatcher came to power, people would have been far more embarrassed about being so individualistic and concerned with physical self-improvement."
But besides the unashamed preoccupation with self-image and health that has evolved in the Nineties, it is perhaps a sign of desperation that people are investing so much of their time and money in practices that are, as yet, clinically unproven. As Professor Marks is keen to point out: "It's not for me to say people should stop doing these things to themselves. I just wish they would go into it with their eyes open and not be brainwashed by people promoting these methods for personal gain."
Irritable Bowel Syndrome.
Symptoms: pain in the colon, diarrhoea and/ or constipation, flatulence, abdominal distension, rumbling. Provoked by tea, coffee, bowel overgrowth with bacteria, candida, bran, stress, and psychological factors.
Common in Asia. May be caused by a deficiency of the naturally occurring enzyme lactase, which breaks down sugar lactose. Treatment involves exclusion of milk and milk products.
A "naturopathic" concept - not proven to be an allergy. Symptoms: sleepiness, flatulence, bloating, general depression. Sufferers have to avoid all wheat products, including bread and pasta.
case history one: wheat intolerance
Helen, 32: Three years ago, I started to feel chronically tired. I just had no energy left at all, and knew that something was wrong. It would never have occurred to me to visit a homeopath until friends at work encouraged me to go to one they knew.
We discussed my symptoms, which were extreme lethargy, migraines, bloating, and a painful stomach. I told them about my diet and they suggested it could be an intolerance to wheat. They explained that possibly I lacked a certain enzyme in my digestive system that breaks it down.
As soon as I cut out foods containing wheat, I regained my energy. The transformation was so quick. From not really being able to walk to the shops I can now play tennis twice a week. But if I have a slice of pizza I fall asleep immediately.
It is a nightmare planning your meals, because there's so much you can't eat and it's always surprising to find out how prevalent wheat is - even soy sauce contains it. Socially it's difficult, because I can't go near Italian restaurants. I live on Chinese, Japanese, and Thai food.
It's also difficult trying to explain your complaint to other people. Usually they haven't heard of it and just assume you are exaggerating. My GP has also been very unhelpful.
The problem is the less wheat you eat, the more intolerant of it you become. Sometimes I've eaten it without realising and, after about half- an-hour, my stomach is extremely painful and I feel incredibly tired. It's a much worse reaction now that I consciously avoid it.
As soon as I altered my diet, I lost three stone. The problem is, I can't digest wheat and so it turns straight into fat. The worst aspect was the extreme lethargy, which also made me feel depressed. Since I've discovered what's wrong, the difference in my life has been phenomenal.
case history two: irritable bowel syndrome
Antonia, 28: I was diagnosed with Irritable Bowel Syndrome almost as soon as I moved to London four years ago. About once a month, I noticed, my stomach would swell up and feel inflamed after a largish meal. This began to increase over several months until the whole area under my bellybutton was painful every time I ate. When this happens I get intense stabbing pains for about an hour. Often I alternate between quite extreme diarrhoea and then constipation.
Consequently, I am preoccupied about how near I am to the toilet whenever I'm out. The first thing I do if I'm in a restaurant is check where the loos are and try to sit near them. I'm absolutely terrified of being stuck somewhere and not being able to get to one in time.
Apart from that sort of anxiety, there's the social embarrassment of what I look like. I often have to stay late at work and by early evening I have to unzip my skirt because my tummy has got so big. I always wear baggy tops to conceal my figure. Even so, people often give me a seat on the Tube and assume I'm about five months pregnant.
I've been to the doctor several times; each time they've told me to try to eliminate different foods to see which one is causing a reaction. I'm intolerant to most dairy products, and beer is also something I have to avoid. I've booked an appointment with a homeopath, which is really my final resort. The only thing I wouldn't try is colonic irrigation - I've heard that can inflame your stomach even more.
I'm at the stage where it's starting to affect my body perception. I'm constantly self-conscious and my wardrobe is full of loose-fitting clothes. The worst aspect is feeling so overweight - I don't feel happy with my body at all.