We reject certain foods for a reason, and by finding out why, we can try to overcome the aversion. Have you ever trained yourself out of a food hatred?
Like favourite childhood scars, food aversions are deeply personal, often come with a backstory, and are ripe for comparing with others. This is classic ice-breaking conversation territory in the west, where there is no shortage of foods to happily loathe without risk of malnutrition. When I was little, being the only one in nursery who didn't partake in the free milk (yuck!) made me feel special. Taking refuge under my aunt's dining table, during a particularly smelly cheese course, gained me so much attention that the event has become family lore.
Nowadays, I'm ashamed of my childish rejection of certain foods and have been working on beating them. But I take reassurance from the fact that most people can drum up at least one item they won't eat. Fresh celery is the "devil's weed" to Guardian restaurant critic Marina O'Loughlin . And even Angela Hartnett can't stand coriander and desiccated coconut.
Whys and wherefores
Part of the fun of food-aversions chat is trying to explain them. People sometimes deduce that I'm allergic to dairy but I can eat cheese and the likes of gooseberry fool until, ahem, the cows come home. To get to the bottom of it, I call the psychology professor who has all the answers in this field, Paul Rozin of the University of Pennsylvania. Only, it turns out that, as far as most idiosyncratic aversions are concerned (the commonest type of food dislike), there are no answers.
Rozin and Jane Kauer, also of Pennsylvania University, are working on a paper that involved surveying nearly 500 people about their hatred of, say, raw tomatoes or white foods. Most had no idea what sparked these aversions, but they tended to have started in childhood.
Very few innate aversions do the rounds. So-called supertasters are oversensitive to bitter and some other tastes. And Hartnett has probably inherited the OR6A2 or "coriander-hating" olfactory gene. But it is possible to train ourselves out of these. Rozin himself, who is not immune to the joys of sharing food foibles, is "hypersensitive to bitter, so I can't drink coffee, but I love dark chocolate. It's sort of weird." It has taken him 20 years of concerted effort to appreciate beer, "but it is bitter", he winces.
Some people (especially kids) are simply more food neophobic - less accepting of new tastes - than others. "We can measure that," says Rozin. But otherwise, flavour preferences are learned. One of the secrets of homo sapiens' success is that we're naturally omnivorous. We can get nutrition from many sources.
The best-known reason we become averse to foods is as a result of them making us sick. (Although this doesn't explain most quirky food hates, says Rozin.) It's not a conscious thing; brains do it to protect us from further poisoning. But they can get it wrong. If you eat something new - say sea urchin - the same day some bacteria in your regular salad get the better of you, your brain will probably choose sea urchin over salad as its new nausea trigger.
It's a powerful process. If you nibble your favourite comfort food when you've got flu, you could unwittingly be programming yourself to go off said food. For this reason, people are often advised to lay off beloved foods when undergoing chemotherapy.
That said, these aversions can be reversed, especially if the culprit is something you've eaten many times before with no ill effects.
Learning to love thine enemy
When the American food writer, Jeffrey Steingarten, switched careers from law to gastronomy, he felt duty-bound to overcome his many food-hates, which included anchovies, kimchi and Greek food (yes an entire national cuisine). He simply ate and ate and ate these foods until his prejudiced palate relented.
There is a well-documented psychological phenomenon whereby "mere exposure" to anything results in an increased liking for it. But when it comes to food, there's also a physiological reason why familiarity increases preference. A study published last month by Dana Small of Yale University has demonstrated this for the first time in humans. "When you ingest something," says Small, "all these hormones are released. Your blood glucose changes, you've all these metabolic effects that are critical for changing the brain's representation of flavour. If you experience a novel flavour and experience positive post-ingestive effects, then the next time you ingest that flavour you'll find it better and will be more likely to eat more of it."
Happiness makes food taste better
Never underestimate the positive effects of mood and circumstance. Surely I'm not the only one who has recoiled at the thin, tart-yet-deliciously-cheap local wine on the first night of a holiday, only to be basking in glass upon glass by the end. Exposure + good times = love. Then there was when I met the brother I never knew I had for the first time. He cooked his favourite pasta dish, with about 1,000 olives. I despised olives, but so delicate was the situation that I couldn't possibly let on. By the end of the meal, I bloody loved olives.
The third way
Steve Tromans uses a combination of hypnotherapy and neuro-linguistic programming to treat people with extreme aversions, his modus operandi is to get his clients to think the same way as someone who can eat the food in question. "I saw a woman recently," he says, "who had only eaten chips, white bread, strawberry jam, nuggets and burgers since the age of three." She had nearly choked to death around that age.
This woman was asked to imagine eating a piece of orange. Impossible, she said. He then asked her to close her eyes and imagine someone across the room eating it. They named her Barb, and she looked just like the client. Tromans suggested other "camera angles" from which to picture this eating - and before the client knew it, she had a Barb's-eye view. "I thought, I'm going to carry on doing this until she realises she is imagining eating it," says Tromans. "By the end of the session she could eat nine different fruits."
I recently bit the bullet and sipped some milk to find I didn't even dislike the taste. I still don't like the idea of it, though. Next, I upped the ante with some feta cheese. I got some quality stuff that lacked that rancid punch, and by day three the goaty aftertaste was becoming quite acceptable. Easy. The main challenge is finding the time and inclination to eat stuff you don't fancy. Have you trained yourself out of a food hatred? How did you do it?
'I despised olives. But when I met the brother I never knew about for the first time, he cooked his favourite pasta dish with about 1,000 olives. By the end of the meal, I bloody loved olives.' Photograph: Julie Woodhouse/Alamy