For almost half of Yemen's 22 million people, eating has become a luxury they can't always afford.
On a bad day, Umm Ahmad and her family of five, who live in Sanaa's shanty-town district of Al-Sunaina, go without any food at all.
On a better day, Umm Ahmad's husband, who works as a vendor, selling baby clothes in the market, comes home with "500 Yemeni riyals (about $2.30/1.79 euros) and we eat."
"Have pity on us," she says, breaking into tears as she clutches her sick and hungry daughter Amira and describes her family’s daily struggle to survive.
She fears for Amira's life. Lifting the five-year-old's dress and pulling up her sleeves, she reveals skinny and slightly bruised limbs, a consequence she says, of a blood disorder for which they cannot afford treatment.
In the past year alone, according to the latest UN report, the cost of basic foodstuffs has surged by between 40 and 60 percent and the price of always scarce drinking water has risen by 200 percent, contributing to skyrocketing inflation.
Unemployment rates have also soared, and 10 million Yemenis, out of a total population of about 22 million, struggle to put food on the table, the UN says.
The popular uprising that ousted veteran leader Ali Abdullah Saleh and the months of political unrest that followed has crippled the government’s already weak and corrupt institutions.
The result, says the chief UN representative in Yemen, Ismail Ould Cheikh Ahmed, is "a much more profound and much more deep humanitarian crisis than what we have been describing."
Evidence of the crisis is clear, not just in the country’s distant provinces where government services are weakest and international aid is hindered by ongoing conflicts, but also in the capital Sanaa.
Sharing a single room with her two daughters and father, Fatima Hawsali says life in the past year has gone from "bad to worse."
No one in this Yemeni household has an income. They rely on government hand-outs, which they say have become increasingly unreliable.
"We fight death" every day says Fatima's father, Rizq.
Neighbour and local store-owner Haidar Saleh lends people bags of rice, sugar and flour on credit, but he too is struggling.
Two notebooks sit on his shop counter: one detailing debts owed to him by residents of the neighbourhood, the other, debts he owes to his suppliers.
Signup to our newsletter and follow us on Facebook and Twitter!
"I can't pay them because my customers don't pay me," said Saleh.
These are the humanitarian facts: About 55 percent of Yemenis live below the poverty line on less than $2 dollars a day. Ten million are "food insecure," and five million of them are "severely food insecure."
Almost one million children, an estimated 967,000 under the age of five, are suffering from "acute malnutrition," and more than a quarter of them "are at risk of dying" unless immediate action is taken, the report says.
The health sector, which was barely functioning before the 2011 Arab Spring-inspired uprising against Saleh, has suffered major setbacks.
Measles has made a comeback, killing a total of 170 children, most of them since January. Other communicable diseases have re-emerged, including cholera and dengue fever.
Unemployment among the country's youth, considered a major destabilising factor, has risen to 53 percent.
Investors have pulled out and businesses have shut down, creating, according to the latest UN estimates, an $8 billion loss in private sector revenues. That has dealt a severe blow to the economy of what was already the poorest country in the Arab world.
The even bigger problem, says Cheikh Ahmed, is that "there's very little (international) interest in this."
"Everybody speaks only about the politics, about the security issue, but that's only half the story ... this is a disaster," he said.
If the humanitarian crisis is not resolved, he warns, it will threaten stability and derail the already delicate political transition process that gave rise to Yemen’s first new president in 33-years.
The grim humanitarian reality has been in the making for years, but the current crisis has "aggravated" already severe underdevelopment, says Cheikh Ahmed adding that even if the latest unrest is resolved, "we will still have major needs in this country."
In a coffee shop in one of Sanaa's few middle-class neighbourhoods, prominent economist and university professor Mohammed al-Maitami cautioned that Yemen is "totally incapable of resolving ... the mine-field of challenges" that lie ahead.
"We need major and sustained international support," said Maitami. On the humanitarian front, that support has been slow in coming.
The UN in partnership with international NGOs has launched an emergency appeal for $455 million for 2012. To date, it is only 42 percent funded. Education has received no funding at all and the water, sanitation and hygiene cluster is only 12 percent funded.
Protection, a key sector that works to prevent the abuse, neglect and exploitation of Yemen's most vulnerable groups, including women and children, is only 8 percent funded.
"This is certainly a worrying development for us" said Cheikh Ahmed.
Even worse, he says, the aid community now believes they will likely need more than what they have already asked for, most of which still has not been received.