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One of the UK's largest teaching unions is calling for schools to ban energy drinks from their premises.

The NASUWT is warning about caffeine levels in the drinks, describing them as "readily available legal highs" which can contribute to poor behaviour.

It follows a report by academics, seen by 5 live investigates, calling on the government to consider making the sale of the drinks illegal to under-16s.

But the British Soft Drinks Association says the drinks have been deemed safe.

'Legal highs'

Academics from FUSE - the Centre for Transitional Research in Public Health in the North East - found children as young as 10 are buying energy drinks because they are "cheaper than water or pop".

Children told them they buy the drinks for as little as 25p, and that they choose energy drinks to "fit in" or "look tough".

They also found that the drinks are targeted at young people online in pop-up adverts, on TV, in computer games, and through sports sponsorship.

A typical energy drink contains 32mg of caffeine per 100ml and cans carry warnings saying they are "not recommended for children".

A single 500ml can contains 160mg of caffeine, equivalent to around two shots of espresso coffee.

The researchers highlight European Food Safety Authority (EFSA) guidance which recommends an intake of no more than 105mg caffeine per day for an average 11-year-old. They also point out that young people in the UK are among the highest consumers of energy drinks in Europe.

Figures from the British Soft Drinks Association show sales of energy drinks increased by 185% between 2006 and 2015, equating to 672 million litres consumed in 2015, and a total market value of over £2bn.

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Darren Northcott, NASUWT national official for education, said: "Teachers have registered concerns with the NASUWT about the contribution of high energy drinks to poor pupil behaviour as a result of pupils consuming excessive quantities of these drinks.

"They are popular among young people who often think they are just another soft drink, and young people and parents are often not aware of the very high levels of stimulants that these drinks contain.

"They are readily available legal highs sold in vending machines, supermarkets and corner shops."

He added: "The evidence of the impact of these drinks, including that uncovered by 5 live, is compelling and serves to emphasise that further action needs to be taken.

"The NASUWT has always been clear that drinks with high levels of sugar should not be sold on school premises. It is time to look again at the School Food Standards, and the enforcement of the standards, to make sure that every school in the country is free of highly-caffeinated soft drinks, as well as those that are high in sugar."

Energy drink 'for breakfast'

Victoria Stean, from Milton Keynes, started consuming energy drinks when she was 16 and was soon drinking around seven 500ml cans a day.

She said: "I was definitely hooked. I would have a can for breakfast, another one mid-morning, and several in the afternoon.

"It took me a while to wean myself off energy drinks. I would get headaches if I didn't drink them. Since I have stopped drinking them I have lost weight and my vision has improved again.

"Ironically, I also have more energy now and I sleep better."

Image copyright Victoria Stean Image caption Victoria was able to lose half her body weight after she stopped drinking around seven 500ml cans of energy drinks a day.

Norman Lamb, chair of the Commons Science and Technology Committee and a former Liberal Democrat health minister, said: "The potential health risks and impact on sleep of energy drinks is something I would like the committee to consider evidence on in the new year.

He added that "given epidemic levels of consumption among under-16s we have to consider banning the sale of these drinks to that group".

In a statement, the British Soft Drinks Association, which represents manufacturers, said: "Energy drinks and their ingredients have been deemed safe by regulatory authorities around the world.

"In 2010 we introduced a voluntary Code of Practice to support consumers who want to make informed choices. In 2015 this was updated to include more stringent guidelines around marketing and promoting, including reference to in and around schools."

The Food Standards Agency said: "The FSA reviews guidance when significant new work in the subject area becomes available. Our current guidance was developed following the European Food Safety Authority's assessment of caffeine in 2015."

5 live Investigates: Energy Drinks is broadcast on Sunday 10th December 2017 at 11am GMT. If you've missed it you can catch up on the iPlayer.

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