Viewed side-by-side, scans showing the brains of a chronically malnourished infant next to a healthy baby can look startlingly different. In the well-fed child, a rich, bushy network of fibres is starting to fill the skull. In the malnourished child, that network is markedly smaller and full of gaps.
Those gaps represent more than just a curious biological image. That lack of brain development will mean that as a child grows, they are likely to do less well at school, they are then likely to earn less and they are then more likely to end up in poverty. The damage is also largely irreversible. While they are also physically smaller and more prone to disease than a well-fed child, it is the slowed brain development that is so pernicious.
If a child is not fed enough in the first 1,000 days of life, the effects can last a lifetime explains Chris Kaye, Pakistan director of the United Nations World Food Programme (WFP).
“The problem is the cerebral growth is inadequate,” he says. “The connections are not made and that is the issue which causes such a lasting impact over years in terms of the child's ability. With the absence of effective cognitive growth at that age, it impacts them throughout their entire life.”
Worldwide, the physical and mental effects of this chronic malnutrition, known as stunting, affect some 150 million children under the age of five, mainly in Africa and Asia.
The Covid-19 pandemic is likely to make that worse as the economic fallout from lockdown precautions pushes more families into poverty and makes food harder to buy for the poorest.
The WFP forecasts the number of people suffering struggling to get enough to eat will double to 270 million by the end of this year and mean millions more hungry children.
Pakistan, which at more than 210 million inhabitants is the world's sixth most populous nation, has had shocking rates of stunting for decades. A 2018 nationwide nutritional survey found two out of five children under five showed some signs of stunting. In some of the poorest and most rural districts that can be closer to 60 per cent.
Beyond the personal cost to those affected, for developing countries this stunting also carries a huge economic cost. The lost potential and productivity of workers is estimated to cost Pakistan three per cent of its GDP, or £6bn, and it is predicted to get worse.
In a world of evolving technology such as artificial intelligence, future workforces are expected to need better education and skills to keep up. Those hampered from birth will fall further behind.
“Stunting is a very significant problem because we are walking into a technological age where human capital is going to determine the success of nations,” explains Dr Sania Nishtar, who advises prime minister Imran Khan on poverty alleviation and social welfare.
“It's not like the cotton mills of the industrial era. The people are the currency of progress. Out in rural Pakistan, the cognitive abilities are being so badly influenced by the lack of nutrition and a host of other deprivations.”
Pakistan's levels of stunting have remained stubbornly high, barely falling at all since at least the mid-1980s. “If you look at the trend lines, they are almost horizontal,” says Dr Nishtar.
After decades of little reduction, it is now Imran Khan's turn to see if he can do any better.
The former cricketing star raised the issue during his inauguration speech and has now added a child nutrition package into his flagship Ehsaas welfare state programme, being delivered by Dr Nishtar.
The new programme, called Nashonuma, which is Urdu for nourishment, is being rolled out across the country to deliver a mixture of cash and food supplements to those at risk.
The critical first 1,000 days of development that can be so badly hit by malnutrition equate to development within the womb, followed by the first two years of life.
Pregnant women and children below the age of two can enroll on the programme if they are poor enough to qualify for the wider Ehsaas safety net.
The programme follows research that handing out supplements alone is not as effective at cutting stunting as a mixture of education, money and dietary supplements, tied to measures to ensure those signed up stick to the programme.
In a sweltering government building in Rajanpur, in southern Punjab province, Nusrata is one of those who can benefit. Her toddler son accompanying her is too old for the programme, but she herself qualifies because she is pregnant. First she has her details taken for the digital registration, and then she hitches up her salmon pink burka so health workers can weigh and measure her.
Though it looks as though there is nothing to her, measurement of the circumference of her upper arm shows she is not classed as malnourished - though she is close. She still qualifies for sachets of food supplement, which contain a thick, nutrient-rich paste the consistency of peanut butter, because the programme is also preventive.
Every sachet is individually numbered to try to stop them being pilfered or sold off and beneficiaries must bring back empty packets to get a new batch. She also has to watch an education video and ensure her immunisations are up to date.
The cash side sees pregnant women and boys given 1,500 rupees (£7) per quarter. Girls are given 2,000 rupees (£9) instead.
“We want them to value girls,” Dr Nishtar explains.
The idea is that the extra money and education encourage parents to buy more varied and healthy food than the endless rice and bread which is the lot of many poor.
“When you are empowering these women, you will observe when you give money to them, you are giving choice to them,” says Dr Yasir Ihtesham, a nutritional expert with WFP. “Now they are informed. When they go through the market to home, they buy lots of things. I have seen it.”
Nusrata's circumstances illustrate another difficulty of tackling stunting however. At just 26, this will be her sixth child. A lack of family planning and the early marriage of young girls contribute hugely to the poverty that causes the problem. Around half of Pakistan lives in poverty and a varied diet is often out of reach.
Anaemia and vitamin deficiencies are widespread among women and mean that poor, malnourished mothers will go on to give birth to malnourished babies, says Prof Sajid Soofi, a public health expert at Karachi's Aga Khan University.
“It is a cycle,” he said. Pakistan's failure to tackle this poverty around stunting had hampered previous efforts to fix it.
The prevalence of stunting in Pakistan is so high that even a modest improvement would be a success.
“If we can bring it down by five per cent within this time span it would be a huge achievement,” says Dr Nishtar.
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