By Alastair Leithead
BBC News, Wakhan Corridor, north-east Afghanistan
Alex and Eleanor Duncan have taken their family to Afghanistan
Strolling out along the narrow tracks between the streams and the golden wheat harvest, Dr Alex Duncan is clutching a set of children's scales and is off for his first consultation of the day.
With him are two of his daughters, Ruth, three, and two-year-old Libby, who jump around the fields and irrigation ditches as if it was their back garden.
Which of course it is, as they have lived in this village high up in the Wakhan Corridor of north-eastern Afghanistan all their lives while mum and dad have been trying to improve the health of some of the poorest people on earth.
"We're just on our way now to see a man who is being treated for tuberculosis to see if he's gained any weight," said the 42 year old general practitioner from Sussex.
It's harvest time in the Wakhan and everyone is out cutting the ripened crops into bundles with small metal sickles and preparing the grain for the long winter ahead.
Eight donkeys, heads roped together in a line, are whipped with a stick and screamed at by a small boy to make them walk in circles over the golden crop, their hooves breaking the wheat grains from the stalks.
In another field the farmer is further on - here the pile of grain and chaff is tossed up in the air with pitch forks to separate it once again.
Then the brightly-dressed Wakhi women, wearing red and purple materials, unusually for Afghanistan with their faces uncovered, step in and sieve the wheat grains down even further into a sack.
It's a six-week process which would take a combined harvester two hours, but there is no mechanisation here. Everything is done by hand, and if the cold and the snow comes early it's all ruined and families will go hungry.
"All Wakhi houses are the same," explained Alex as we dipped our heads through the small, narrow doors and into the big room which is for living, cooking, eating and sleeping.
"You have a tandoor oven in the middle for baking bread and a hole in the roof for the smoke to go out, but it goes out very slowly so when they are cooking the whole house fills with smoke, and this increases child mortality from respiratory diseases by about 10%."
It's one of the reasons he has discovered to explain a terrifying death rate among children - when he arrived a third died before the age of five. Now it's down to a quarter.
The number of deaths was a big shock to his wife Eleanor, a linguist, who has taken on the role of talking to the local women and teaching her own children every day - Ruth, Libby, Anna and Jacob, who's the eldest at eight.
"Their lives are really hard and sometimes tragic - often tragic. It's not unusual for women to lose a child or two children or maybe even three," she said.
"We have a neighbour who lives up the hill who has lost eight children and it's just heartbreaking really to see that.
Wheat is a vital part of life for people from the Wakhan Corridor
"We found it really, really hard as we come from a culture where children don't die and here they just do die, a lot, and we had to learn from local people that they accept that this happened."
But through learning the Wakhi language, an archaic form of dari or Persian, the Duncans discovered there were a few simple things that could make all the difference.
Firstly women would not give babies breast milk for three or four days after they were born as they thought the first milk would be bad - in fact it contains vital nutrients.
There was no deep-set cultural reason for this and so women were trained to pass on the word that the milk was good, and that has had a huge impact.
New stoves with chimneys have been designed by the community and are being tested to reduce the smoke.
And people now understand that first-cousin marriages can cause abnormalities in the children.
The Duncans have monthly child weigh-ins under a big willow tree - and in 25 other villages, monitoring their progress and offering supplements to the most vulnerable.
Vaccinations are also given out by local health workers they have trained - it's making a difference and basic education for the women is helping reduce the number who die in childbirth, which is also a terrifying figure and one of the worst in the world.
The poor road means access to health care is beyond the reach of most, and Dr Alex's real answer - more girls being educated - is hindered by the lack of schools with decent teachers and few bridges, which means it's often too far for girls to walk to the nearest school.
Dr Duncan can hold clinics in such places as underneath trees
And it's not an easy place to live for this highly-dedicated British family.
They have a typical Wakhi one-roomed mud hut too, with no running water or drains, a pit latrine, no beds and little food other than the local bread, a little bartered rice and whatever they can cram onto the truck that drives up from Kabul once a year.
The whole family hunkers down on the floor under blankets every night, and the winters are especially harsh, with temperatures as low as -25C and just five hours of sunshine a day in the narrow valley bottom.
Handing out pills from the back of his white van - the mobile clinic - I asked Dr Duncan whether it was all worth it.
"Oh yeah," he replied, quite energetically. "No question about it. We're not going to be here forever, and we are having an effect on the health of the population which we couldn't do in the UK and that's a very satisfying feeling.
"It's not easy. You can't change the world in a day or save the world in six weeks, but slowly, slowly we can make some inroads. It's very hard, but it's very good."