Almost a million adults and children received emergency supplies from food banks in the past year, a "shocking" rise of 163% on the previous 12 months amid rising living costs, low pay and welfare problems, a new report has revealed.
The Trussell Trust said rising numbers were turning to food banks because their incomes are "squeezed", despite signs of an economic recovery.
A record total of more than 913,000 people received three days' emergency food in the last year, with over half blaming benefit delays or changes.
The trust now has more than 400 food banks across the UK, although it is opening two a week compared with three in 2012/13.
The Trussell Trust's chairman, Chris Mould, said: "That 900,000 people have received three days' food from a food bank - close to triple the numbers helped last year - is shocking in 21st-century Britain.
"But, perhaps most worrying of all, this figure is just the tip of the iceberg of UK food poverty. It doesn't include those helped by other emergency food providers, those living in towns where there is no food bank, people who are too ashamed to seek help or the large number of people who are only just coping by eating less and buying cheap food.
"In the last year we've seen things get worse, rather than better, for many people on low incomes. It's been extremely tough for a lot of people, with parents not eating properly in order to feed their children and more people than ever experiencing seemingly unfair and harsh benefits sanctions.
"Unless there is determined policy action to ensure that the benefits of national economic recovery reach people on low incomes, we won't see life get better for the poorest any time soon.
"A more thoughtful approach to the administration of the benefits regime and sanctions in particular, increasing the minimum wage, introducing the living wage and looking at other measures such as social tariffs for essentials like energy would help to address the problem of UK hunger."
The trust said its food banks were now offering welfare advice and providing essentials such as washing powder, nappies and hygiene products to families at "breaking point".
A letter signed by 36 Anglican bishops and more than 600 church leaders from all major dominations calls for urgent Government action to tackle food poverty.
A public vigil will be held tonight in Westminster to highlight the issue.
A Department for Work and Pensions spokesman said: "We're spending £94 billion a year on working age benefits so that the welfare system provides a safety net to millions of people who are on low incomes or unemployed so they can meet their basic needs.
"Even the OECD say there are fewer people struggling with their food bills compared with a few years ago, benefit processing times are improving and even the Trussell Trust's own research recognises the effect their marketing activity has on the growth of their business.
"The truth is that the employment rate is the highest it's been for five years and our reforms will improve the lives of some of the poorest families in our communities by promoting work and helping people to lift themselves out of poverty."
Shadow environment secretary Maria Eagle said: "The vast increase in the number of households and families turning to food banks reveals the shocking truth of life under David Cameron's cost-of-living crisis. While those at the very top get a tax break, everyone else is finding life is harder under the Tories.
"Instead of hiding behind the Tory myth, that says the increase in food banks is driving demand, it is time ministers got a grip and took this issue seriously."
Steve Turner, assistant general secretary of the Unite union, said: "These shocking figures show that the Government is in denial about its food bank shame.
"It's a national scandal that, in the seventh richest country in the world, nearly one million people were forced to turn to food banks in the last year.
"These aren't people who are turning to food aid out of choice. They are people being plunged into food poverty because of this Government's draconian policies, which are hitting some of the most vulnerable while a cost-of-living crisis grips ordinary families struggling to make ends meet.
"Food poverty is becoming a growing stain on this out-of-touch Government's record as the so-called recovery passes ordinary people by."
Leaders of the Methodist Church, Baptist Union of Great Britain and United Reformed Church said the figures should spark "shock and anger".
Methodist president the Rev Ruth Gee said: "Hunger should not and need not be a problem in a rich country like the UK - and yet clearly it is. We thank God for food banks, which provide a vital lifeline to people who would otherwise be forced to go hungry.
"Wherever I have travelled in my year as president, I have asked the same two questions: do you have a food bank here and have you seen increased need for it?
"Wherever I have travelled, the answers to both questions have been 'Yes' and I am not hearing about small increases in need. I am hearing about huge leaps in demand and food banks that are struggling to keep up."
The Rev Stephen Keyworth, faith and society team leader for the Baptist Union of Great Britain, said: "Over 900,000 people needing the help of a food bank should lead the Government to examine why the post-welfare reform benefits system allows so many people to go hungry.
"Churches and others are doing sterling work reaching out to help folk in need but this isn't how it should be."
Oxfam's head of UK poverty programme, Rachael Orr said: "The fact that the number of people forced to turn to food banks has doubled in the last year and is worsening the situation for people in poverty is deeply worrying.
"Foodbanks and the thousands of people who support them are doing an impressive job in helping stop people from going hungry, but the truth is that in a country as rich as the UK there should not be food poverty at all.
"The Government needs to provide adequate support to the poorest in society and urgently tackle the low incomes and rising bills that are leaving people hungry."