Britain has gone bananas. Over the past 12 months we have consumed an unprecedented 3.5 billion pieces of the tropical fruit, forcing our native apple into a poor second place.

The nation's banana boom is one of the most remarkable nutritional phenomena of recent years, a guide not just to the flowering health consciousness of the British people but also to the country's economic health.

We spend more money on bananas than any other supermarket item apart from petrol and lottery tickets, and more than 95 per cent of our households buy them every week. Bananas are us, it seems.

The addiction will be reinforced this week as TV viewers watch endless Wimbledon shots of tennis players munching their way through hundreds of bananas, a fruit that is now considered to be indispensable for recovery between sets and rallies.

Yet a century ago hardly anyone in Britain had tasted or even seen a banana. The first commercial refrigerated shipment arrived 100 years ago this month, triggering a national love affair from which we have never looked back.

A striking measure of the banana's popularity can be seen in trade figures that show sales in the UK rocketed by more than 150 per cent over the past 17 years, while fruit sales in general have risen by a mere 15 per cent.

Bananas have flourished at the expense of our own apples and pears. Last year alone there was a 9 per cent growth in British banana sales while homegrown fruit languished.

'The banana has everything going for it, so its popularity should not seem that surprising,' said Lyndsay Morgan of the fruit's marketing organisation, the Banana Group.

'It is easy to open; it is packed with energy, fibre and vitamins; it is rich in potassium and low in calories. It is also a first-class hangover cure, stabilises blood pressure and soothes heartburn. And when you want to start weaning babies, mashed banana is the perfect food. You can even use the skins as garden fertiliser when you have finished. It is astonishingly versatile.'

On top of all this, bananas contain chemicals that stimulate the production of serotonin and dopamine, the same neurotransmitters set off by Prozac and Ecstasy. In short, bananas are healthy - and they give you a buzz. It is the ultimate food: ambrosia in a colourful skin.

Indeed some people even believe the banana is proof of God's benevolence. They point out how easy it is to handle and bite; they marvel at its ready-to-use tab for wrapper-removal; they extol its pleasing taste; and they point to its sell-by-date mechanism - its skin turns black. This is celestial confection-making at its best, it is claimed, and shows clear evidence of a deity who created the world for humans.

Most would view such ideas as over-the-top, of course. Nevertheless, the banana retains, for all its popularity, an aura of exoticism. And that, at least in part, explains its special economic importance as a symbol of the potency of Western capitalism.

'Hold our hands and take us to banana land,' chanted groups of East Germans during the fall of the Berlin Wall, as they rose up in rebellion against the austerity of their communist rulers and begged for capitalist redemption.

To them, and many others, the banana - for all its connotations with risqué jokes and pratfalls - meant freedom, at least in terms of middle-class affluence. If you have access to bananas, you must have control of world trade and shipping. And if you do, things surely cannot be that bad.

It is a point underlined by Tony DeNunzio, Asda's chief operating officer: 'Bananas are a very important economic barometer, as well as being the best-selling item in our stores.'

The rise and rise of the nation's favourite fruit has also been the result of some skilful and cunning marketing by traders and producers - as well as the influx of cheap 'dollar bananas' from Latin America and the Caribbean.

And here lies the downside to the banana's popularity. As campaigners point out, banana plantation workers are usually paid a pittance. Many have to live in miserable housing in near-starvation and are left sterile by toxic agricultural chemicals. Some of their trade union leaders risk being attacked and killed.

As a result, some supermarkets, such as the Co-op, now offer Fairtrade bananas which have been bought directly from growers who are guaranteed realistic prices for their product. Such schemes are already helping farmers in Costa Rica, Ghana, Colombia and Ecuador. Some 10,000 tonnes of Freetrade bananas were sold in Britain last year, but this represents only a fraction of our supermarket sales. Last year 725,000 tonnes of bananas were sold in Britain. Of these, 24 per cent were bought in Tesco, 15 per cent in Sainsbury, 13 per cent in Asda, 6.4 in greengrocers; 4.2 per cent from the Co-op; and 3.6 cent from market stalls.

Crucially, increasing numbers of these bananas are being specially packaged - for example, in kids' packs, using smaller fruit, or in 'Eat Me - Keep Me' bags in which fruit at different stages of ripeness is sold to help once-a-week shoppers.

It is this type of calculated, aggressive marketing that has helped keep the banana at the forefront of British shopping and a staple in virtually every household. Annual consumption now stands at 26.6lb per person, the equivalent of two bananas a week for every man, woman and child in the British Isles. This is an annual trade now valued at more than £600 million.

Bananas were virtually unheard of during Victorian times. Early attempts to introduce them to our northern climes met with failure because by the time they had been picked, packaged and then shipped to the UK they had rotted beyond recognition. (Some did reach our shores, however, as was revealed by a recent archeological excavation in London in which the remains of a sixteenth century banana were dug up.)

The development of refrigerated shipping changed everything. Then, as now, bananas were imported in bunches to ripening houses in dockyards where they were stored until they had turned a greenish-yellow colour. Then they were broken into individual fingers and transported to stores and markets.

At times of war, however, bananas disappeared from Britain. In World War I, this shortage led to the popularity of the music hall song 'Yes, we have no bananas', written by Leon Trotsky's nephew.

Similarly, during World War II bananas disappeared from shops. When transatlantic shipping re-commenced at the end of the war, the return of the banana was hailed as heralding an end to austerity and to the curse of the ration book. The Labour government even instigated a national banana day in 1946. Every child should have a banana that day, it was decreed - sometimes with unfortunate results, as the writer Auberon Waugh recalled. He and two of his sisters received their quota of three precious bananas, an exotic fruit whose deliciousness they had heard of but never experienced.

'They were put on my father's plate, and before the anguished eyes of his children he poured on cream, which was almost unprocurable, and sugar, which was heavily rationed, and ate all three,' Waugh wrote. 'From that moment, I never treated anything he had to say on faith or morals very seriously.'

Additional research by Hannah Richards

www.thebananagroup.uk.net