IT has become a breakfast favourite in our increasingly health-conscious age.

But the avocado mashed on toast at hipster eateries across the land may not be quite as green as it first appears.

New research shows the dark-skinned superfood - botanically classed as a berry with a single large seed - can travel more than 6,000 miles before it reaches our plates.

It is among a range of produce that is transported across the globe before arriving in Britain, sparking questions over how fresh, beneficial and environmentally friendly our fruit and vegetables really are.

According to a report commissioned by The Mushroom Bureau, the avocado tops the charts, covering up to 6,263 miles from Peru on its journey to the UK.

It is followed by the cucumber (3,428 miles from Israel) and the onion (2,608 miles from Egypt).

However, while we now have access to a wider range of foods than ever before, distance and hours spent in transit inevitably affect quality, both in terms of taste and nutritional composition.

Many people are also completely unaware of just how far produce has travelled, despite the implications this has for its carbon footprint.

Staff at The Mushroom Bureau - a partnership between local farmers and growers - revealed that three quarters of survey respondents had never looked at the label to check for origin.

Furthermore, nine in ten had “no clue” when well-known vegetables are in season. Agriculture and horticulture leaders said the research highlighted the importance of domestic food production.

“The UK has one of the highest obesity rates in Europe and diet plays an important part,” said Jack Ward, Chief Executive at the British Growers Association.

“In many cases both adults and children don’t have enough vegetables and fruit in their diet. Increasing the consumption of veg and fruit is crucial together with increasing our capacity here in the UK to meet the extra demand.”

He added: “There’s a big opportunity out there for the British agriculture and horticulture sector to play an important role in transforming the health of the nation, for us to grow our share of the UK fruit and veg market.

“Undoubtedly, Scotland - where you grow a significant amount of berries, as well as green peas and brassicas - would be a key part of delivering on that ambition.”

Farming leaders north of the Border have also stressed the need to support domestic producers.

In a recent open letter to consumers, NFU Scotland President Andrew McCornick said: “The backing given to Scottish farming, food and drink throughout the [coronavirus] pandemic has been unprecedented and reinforced how much you value healthy, nutritious, local produce and the standards to which it has been grown or reared.”

He added: “I ask that you further support our domestic food production by writing to your elected politicians and supermarkets on the importance of domestic production.

“Highlight that you want our production standards to be protected now and in the future, and that you want enhanced country of origin labelling so that you can buy Scottish or British when given the choice.”

A spokesperson for The Mushroom Bureau said: “Understanding seasonal eating can help when buying the freshest, most nutritious vegetables, a little closer to home. The Seasonal Vegetable League Table brings to life just where our vegetables come from, when out of season and helps people support local farmers who produce high quality veg right on your doorstep.”