This is a letter of apology to all the dinner companions, hosts and cooks I have offended over the years with my eccentric eating habits. I am the person you dread coming to dinner. I am not a vegetarian. I do not have food allergies or a medical condition. Nor is my diet restricted by religion. Nope, I am just plain fussy.

I do not eat eggs, fish, offal, cute animals (venison, rabbit and, obviously, never veal), raw tomatoes or brazil nuts. I have never drunk a glass of milk or a cup of tea, and I don’t intend to.

There is little, if any, logic to my likes and dislikes. For example, eggs are fine if on the crusty edge of a cheesy omelette or in custard, but never boiled, poached, fried or scrambled. I will eat prawns as long as they are not served cold and although I hate milk, sour cream makes just about everything taste better.

But my critics may now have to eat their words because it turns out that I may not merely be faddy, but the victim of a bona fide condition. Picky eating was thought to be something most of us leave behind in the highchair, but it is becoming increasingly common, with a new TV series, Freaky Eaters (BBC Three, Wednesdays, 9pm)on the subject, and experts arguing over whether it is a psychological problem or based more on physical revulsion.

There is an online support group (pickyeatingadults.com) with 500 members, a new UK Living television series dedicated to it, blogs devoted to the problem and a growing interest in clinical circles. Although it is not known how many people are affected, record numbers are seeking treatment.

Dr Bradley C. Riemann, the clinical director of obsessive compulsive disorders at Rogers Memorial Hospital in Milwaukee, is a world expert. He says: “We’ve had more interest in adult fussy eating in the past couple of years than ever before. We used to see one or two cases a year; now we get dozens, and this is at extreme levels. I’ve treated patients from America, Europe and even Panama.” His department is researching causes and whether it is sensory or psychological.

He says: “Sufferers simply cannot stomach some foods. If, for example, they don’t like vegetables, that may not sound like a big deal, but it’s not just vegetables as a side order but vegetables in any shape or form. It can mean they can’t eat something as simple as lasagne. It’s not a case of won’t eat, but can’t eat.”

Deanne Jade, a picky eater and the founder of the National Centre for Eating Disorders (eating-disorders.org.uk), an independent body set up to help with eating problems, says it is increasingly common. “It’s always assumed that people grow out of selective eating as they get older, but in many cases they don’t. I’m an example. Some foods to me just don’t feel like foods. For example, eating certain fruits would be as odd as eating cork or even dog to me.”

Adult picky eating (this is the official medical term, never just “fussy”) has, not surprisingly, been overlooked in favour of life-threatening eating disorders, such as bulimia or anorexia. Dr Nadia Micali, of the eating disorder unit at the Institute of Psychiatry, King’s College London, says: “It was thought that fussy eating is a problem in childhood or a symptom of an eating or obsessive compulsive disorder. We’ve no way of telling how many adults suffer because rarely is it so bad that sufferers see a doctor.”

Most people enjoy thousands of taste combinations, but in extreme cases picky eaters limit themselves to just 20 or 30. Bob Krause, from Virginia in America, founded the support group pickyeating.com. At 59, he knows he will not grow out of it. He eats only crunchy foods, such as celery, and anything with a slimy or runny texture makes him physically sick. He says: “Imagine you lived in a world where the only thing people ate was raw liver. That’s what it is like to be me. I gag on most things and it’s a real embarrassment when it happens in public. People just get offended when you go to their house and never eat the food offered.”

I know how he feels. Last year a friend proudly presented me with her “famous fish and egg” pie. At the age of 32, crying or throwing my plate on the floor were not really options, so I smiled sweetly and ate only the top layer of mash, which was uncontaminated by fishiness, redistributing the rest around my plate. Ten years ago even that would have been impossible. To me the thought of having to chew and swallow pieces of fish or rubbery egg is akin to the insect-eating bush-tucker trial on I’m a Celebrity...Get Me Out of Here!

Claire Simmons, a 33-year-old PhD student, feels the same about fruit and vegetables, and lives on plain meat and potatoes. She has never sought medical help and finds support in the virtual community. Her blog (adultpickyeatersuk;wordpress.com) receives hundreds of views each week. She says: “Dinner parties are a nightmare. Someone once made me a pudding with bananas, which I physically can’t eat. I had to decide which was worse, being rude and refusing it, or gagging. It’s not me being fussy; I couldn’t eat some foods if you held a gun to my head.” Far from being riddled with scurvy or malnourished, Claire, whose mother is a doctor, is fighting fit. “I’m perfectly normal. My weight’s average and I don’t get colds, although I secretly worry that I’ll drop dead of bowel cancer one day.” Her picky eating started when her mother began to wean her.

Catherine Collins, a spokeswoman for the dietitian’s professional body, the British Dietetic Association, says that while cutting out the odd food is fine, eliminating whole groups has long-term health implications. “Although you may look and feel healthy, not eating fruit and vegetables is bad for you,” she says. “Your diet contains fewer antioxidants and fibre, making you more at risk from heart disease and cancer. Diets devoid of vegetables are typically higher in calories and linked to weight gain, constipation and high cholesterol.”

In extreme cases picky eating can seriously jeopardise both mental and physical health. Dr Riemann says: “We have treated people who are dramatically underweight and eat only two or three things; often fried potatoes or fizzy drinks which are bad for them. We’ve had patients who say they can’t socialise because they dread eating out. Usually they’re ashamed and, and in the worst cases it causes depression. Sufferers are isolated and end up underachieving in every domain of their lives.”

I think my fussiness is psychological and stems back to childhood. I ate normally until I was about 6 — around the time my parents separated — when I stopped eating fish fingers and it snowballed from there. Mealtimes became a battleground with my mother. I became a vegetarian, although, bar potatoes and onions, I did not eat vegetables. One infamous (meat-eating) Christmas I ate only a chipolata. The next year I refused turkey, eating it only after my father (who joined us for family festivities) conned me into believing that it was chicken. After I had scoffed my last mouthful, he revealed the poultry truth. My revenge? Vomiting.

Some psychologists believe that fussy eating can be triggered by childhood trauma and, retrospectively, mine could have been a cry for attention. I could not control my parents’ split, but I could control what I ate and, at the same time, unite my parents in concern.

Collins agrees: “A child has no power in family decisions, so a way of gaining some is by controlling what they eat. Then the attention is diverted away from the bigger issues towards concern for the child.” But Dr Riemann believes parents are not to blame and that picky eating is more likely to be caused by phybsical revulsion or anxiety than childhood upset. He is sceptical when I try to blame my erratic dietary preferences on my parents’ divorce, especially as my older sister eats everything, including, once (animal lovers hold your breath), turtle. He says: “For the most part it’s not trauma or memories that are the problem. It’s more about taste, texture, smell and sight. It can stem from an incident. Say you’ ve gagged on meat before, you may develop a fear of choking and become scared of eating anything chewy. It has also been linked to OCD and a fear of dirt and contamination over how the food has been prepared.” Cognitive behavioural therapy is the common treatment as it helps to reset patterns. Dr Riemann says: “Exposure also works well. Say a person eats only soup; we’ll put noodles in it and then work our way up to chicken.” This is Simmons’s approach to overcoming her limited diet. She can now eat cream cheese and smoked salmon and her next target is fruit. She says: “I like to think I’m building up to eating fruit by having fruit juice with bits in.”

Other than the odd embarrassing fish pie moment, my food preferences do not impinge on my life any more and are born more out of habit and whimsy, leading me to conclude that although I eat pickily, I am not an official picky eater.

For further information, visit fussy-eaters.co.uk

Etiquette for fussy eaters

- If you have an allergy, intolerance or are a vegetarian, warn your host in advance. If you are just fussy, try not to be too awkward. If you are given a food you don’t like, your reaction should depend on the social situation.

- If you know the host, either be honest or just say that you are a bit off-colour and, good though the food is, you are just not hungry. Do not then tuck into pudding.

- If you are at your boss’s house for dinner, eat up! If you can’t, then eat around the offending item. There are ways to move food around the plate to make it look as if you’ve eaten more than you have.

- Don’t go on about your likes and dislikes; everyone hates a food bore.

Debrett’s Etiquette for Girls (£17.99)

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