The heavy toll of fighting in Afghanistan can be seen in a set of photos showing UK soldiers before, during and after their tour of duty.

They were taken by photographer Lalage Snow who first met the soldiers from 1st Battalion the Royal Regiment of Scotland during their training.

She says the time she spent with them helped win their trust and get them comfortable in front of the camera.

Three months later Lalage travelled to meet the group in Helmand province.

She said: "I was really shocked at how different they looked: Red-rimmed eyes, beards, really gaunt and thin, brown, and full of sand.

"It really shocked me," she admits.

The photographer says she realised there were lots of good images of soldiers in Afghanistan, but they didn't show how a person could change through combat.

"That's the external manifestation of the scars they bear - it's written in their faces," she says.

As well as the physical change, she also witnessed a shift in the personality of some of the soldiers, particularly the younger ones.

"They had grown up a lot," says Lalage.

"Instead of on training - where they might have been mucking around a bit more - out there it seemed to make them wake up a bit more.

"They were thinking: 'This is real, this is what I'm doing. This is my job - okay get on with it.'"

The realities faced by troops in Afghanistan were also violently reflected in some of the group she photographed.

One of them was injured in an IED explosion, one had to be resuscitated, and another was shot in the leg.

Adjusting to life back in the UK is especially hard for many of soldiers, says Lalage: "Their families for the past six months have been soldiers, guns and sand, rations, living in rough conditions.

"It takes a long time to get used to it."

The main aim of the photos is to shed extra light on post-traumatic stress disorder (PTSD), a subject that's been covered by Newsbeat.

None of those photographed is suffering from the condition. Lalage Snow says she wanted to highlight how PTSD can emerge years after combat.

It occurs when troops are exposed to the death of colleagues and other serious battlefield experiences. The mental health problems can have a dramatic effect on wives, children and other relatives.

"The thing that is most important from the project is the PTSD thing, which I don't think many people are aware of," says Lalage.

"Boys in the Balkans are now getting PTSD, wars from 10-15 years ago."

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