(CNN) -- Kerry Wright didn't feel hungry. Not in the way you might expect. Her tummy grumbled, yes, she could hear it. She just couldn't feel it. She called it "starvation mode."
Wright, a mother of three living in Aberdeen, had hit a low point. But she needed to provide for her children, who then were just entering their teens.
Because there was always so little to go round, it didn't take long before she started skipping meals. She was tired all the time -- and yet she couldn't sleep. She was hungry, but she didn't want to eat, and, if she did, she would sometimes be sick. Her head was frazzled. It was hard to keep a string of thoughts together.
Wright was exhausted but desperate not to reveal the extent of her fatigue to her children. So she would walk around the house with one hand on the furniture, holding herself steady. A severe iron deficiency, she eventually learned, accounted for the terrible fatigue. This went on for about two years.
But it wasn't her own wellbeing that she worried about most. It was her children's. They asked her questions: Why was she dizzy all the time? Why was she taking those pills from the doctor?
And one day she came home to find a glass of milk on the table. Her son, worried about her, had poured it. He made her drink it while he watched -- to make sure she had it all.
"It shouldn't be like that," she says now, remembering. "Kids shouldn't be worrying about their parents like that."
Today, her biggest concern is not that her physical health took a hit, but that her children's mental health did. What psychological scars were left, in the wake of watching their mother starve herself?
It was at a charity that helped local people find employment that someone first mentioned the term "food bank" to Wright. Food banks, which hand out free supplies of food to those in need, have become more and more common. But she flinched at the idea. She was terrified that, should she seek help at a food bank, social services would take her children away.
So Wright came up with a plan. She would apply to become a volunteer at the food bank instead. "It felt a bit better," she says, "for it to be a bit of a trade."
During the first few days, she felt awkward and out of place. But then one of the workers, Kelly Donaldson, took her under her wing. Now and again Donaldson would put a small pack of food together for her new friend at the end of the day. "That's your supper for tonight," she would tell Wright, encouragingly, handing over the bag.
Signs are gathering apace that more and more children in rich countries are experiencing hunger and its negative effects. Recently, the United Nations special rapporteur on extreme poverty and human rights criticised the British government for the scenes of poverty he had witnessed on a trip to the UK. The extent of child poverty in the UK was, he said, "not just a disgrace, but a social calamity and an economic disaster, all rolled into one".
"Children are showing up at school with empty stomachs, and schools are collecting food on an ad hoc basis and sending it home because teachers know that their students will otherwise go hungry," he said.
All of the workers I speak to at British food banks say they have noticed a sharp rise in demand in the past year. One reason cited is changes and cuts to benefits, in particular the new Universal Credit system, which can lead to gaps between payments that leave people unable to pay for essentials.
The Royal College of Paediatrics and Child Health and the Trussell Trust are among those concerned about how food insecurity may be affecting children's health. But what, specifically, would those effects be?
In a phone call to Valerie Tarasuk at the University of Toronto, I mention Kerry Wright's worries about her children's mental wellbeing.
"That's exactly what we need to be concerned about," says Tarasuk.
Tarasuk is a professor of nutritional sciences and an expert on the relationship between food insecurity and health. She also tracks research that explores the long-term effects on children who live in food-insecure homes.
Studies by a team at the University of Calgary, including Sharon Kirkpatrick and Lynn McIntyre, have shown that going hungry just a handful of times is associated with poorer physical and mental health. It also means that children are less likely to finish school.
In one six-year study, McIntyre and colleagues found that young people who had experienced hunger had a significantly higher risk of developing depressive symptoms. Hunger, the researchers wrote, had a "toxic" effect: "Higher odds of chronic conditions and of asthma were observed among youth who experienced multiple episodes of hunger compared with those who were never hungry."
These findings held up even when other things that could influence health were factored in -- hunger really does appear to play a defining role.
"The exposure that children have leaves an indelible mark on them," says Tarasuk. "It's really a bad idea to be leaving so many languishing in this situation."
In the UK, long-term data like that used by Tarasuk and her colleagues is hard to come by. But there are efforts to broaden our knowledge of how food insecurity is related to health.
A major research effort led by King's College London is currently under way in two large boroughs in the south of the capital, Lambeth and Southwark. It's led by Ingrid Wolfe, who is also a paediatric consultant. She says part of her own motivation to become involved in the study was seeing more children admitted to A&E with seizures caused by vitamin deficiencies. "Very, very acutely significant malnutrition," she says.
The Children and Young People's Health Partnership is Wolfe and her colleagues' attempt to understand what things going on in a young person's life may have influenced the condition that brings them to the doctor.
The team are initially focusing on young people who present with one of four "tracer" conditions -- eczema, constipation, asthma and epilepsy. Among the first 1,000 participants with any of the four tracer conditions, food insecurity has turned out to be a concern in 90 per cent of their cases.
In a home where parents or guardians are relying on cheaper food, diets may become less balanced and so intake of micronutrients will decrease as a result. Some of the first deficiencies to emerge might be iron deficiency -- as experienced by Kerry Wright -- along with vitamin A and iodine deficiencies. Iodine -- plentiful in white fish and dairy products -- is particularly important for brain development.
A diet high in sugar can also lead to dental problems. Between 2013 and 2018 there was an 18 per cent rise in extractions of multiple teeth among under-18s in England. This is also associated with food insecurity: dental caries is more common in deprived areas.
And let us not forget obesity. The Royal College of Paediatrics and Child Health says that obesity is correlated with deprivation. "In England it appears that overweight and obesity may be reducing over time in the least deprived but not amongst the most deprived."
Improving diets can't just be done by food banks. But there is another way -- what's called a "person-centred approach".
"I like talking to folk," says Sheena Boyd, with a big smile. "You'll understand that by the end of the day." She laughs heartily. She is a project leader at a charity called Centrestage, based south-west of Glasgow.
When Centrestage was launched, 13 years ago, its founders wanted to provide a theatre group for locals. The idea was to put on big shows with a bit more buzz and pizzazz than is possible for, say, school drama departments. Plus, anyone would be able to join in, no matter their age or background.
It was only as the leaders started working more closely with local communities that they realised food insecurity was such a problem. If you're hungry, you can't be expected to perform in front of hundreds or work for hours backstage.
Centrestage continues to put on community shows, but filling bellies is now a key objective. The group's slogan is "Fun, food, folk."
Centrestage's On the Road project is a bus that travels around and dishes up meals. But before I see the bus, I need to witness the kitchen that churns out thousands of prepared meals every week, says Boyd.
We pull up to a big grey warehouse unit on an industrial estate. But when the door beeps as we enter Centrestage's unit, the smell of cooking suddenly provides colour. Chefs hurry about, all in black and comfy walking shoes, with jugs of various mixtures or huge trays for the ovens.
The food portions cooked here are given to people at Centrestage locations. I try one later -- pasta with roast vegetables, a tasty sauce and some cheese sprinkled on top. A genuinely enjoyable meal. Also available that day was paneer curry with rice, and pots of red pepper soup.
It's a short drive from the kitchens to the bus. The double-decker bus is parked up and, even on a chilly November day, local people are gathered round, sitting outside and having something to eat, or simply enjoying a chat.
On the upper level of the bus there's a soft play area where parents can bring their kids. Here I meet two mothers, each with a young daughter making avid use of the play area. One of the women explains that she has osteoarthritis in her wrist, so cooking at home isn't always easy. Despite this, she has never wanted to use a food bank.
"I didn't really want to take anything off the bus," she says. "Then I heard it wasn't a food bank."
As the bus's driver says, food banks often ask for vouchers -- or "chitties" -- before handing out supplies. "Nae chitties here," he says. Volunteers will happily hand out food for free, though they do ask if people can try to make a small donation.
Either way, no one gets turned away. Between July and September 2018, adults received food nearly 6,000 times and children on about 2,200 occasions.
People's wellbeing can very quickly be affected by hunger, but that's never the whole story. So besides the cheap meals and cooking workshops, Centrestage staff and volunteers aim to help with benefits forms, or housing applications, or employment issues. As Boyd puts it, "We can say, 'Right, what's going on? We can help you in any other way.'"
For Wright, it was working for a food charity that really got her back on her feet. Not access to free food. Today, she expresses a true zeal for the job she does. She now works 29 hours per week at the food bank -- CFINE, in central Aberdeen. She finally has a steady flow of income. This year, she says, she will become debt-free for the first time in a long time. Her children's physical health is good. They have become more active. Now they play sports and one goes to cadets.
And meeting her at CFINE, I get a sense that Wright, like her friend Kelly Donaldson, has found a role that doesn't just help her in the here and now -- it's something she can build on.
Donaldson points out how Wright is clearly happier now. She gets up every day. Puts her make-up on. Goes to work. That makes a huge difference -- for the whole household.
"It does," says Wright. "It has an impact on your children."
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