Millions in the UK are too poor to engage in common social activities, experts have said, as a new report suggests that full-time work is not always sufficient to escape poverty.
Experts are calling on the Government to take action after new evidence showed that the percentage of households that fall below society's minimum standard of living has increased sharply over the last 30 years - despite the size of the economy doubling.
Researchers who carried out the largest study of poverty and deprivation conducted in the UK found the figure had increased from 14% to 33%.
The study said almost 18 million people cannot afford adequate housing conditions, while 12 million are unable to socialise.
One in three people cannot afford to heat their homes properly in winter, with four million children and adults not properly fed by today's standards.
Findings from the project, Poverty and Social Exclusion in the United Kingdom (PSE), based on two surveys, will be discussed at a conference in London this week.
Professor David Gordon, from the Townsend Centre for International Poverty Research at the University of Bristol, said the Government's aims to tackle poverty have "clearly failed."
"The available high-quality scientific evidence shows that poverty and deprivation have increased since 2010, the poor are suffering from deeper poverty and the gap between the rich and poor is widening," he said.
The research found around 5.5 million adults go without essential clothing, while 2.5 million children live in damp homes. Around 1.5 million children live in households that cannot afford to heat their home.
One in four adults has an income below what they consider is needed to avoid poverty, while one in every six adults in paid work is poor. More than one in five had been forced to borrow in the last year to pay for day-to-day needs.
The study, funded by the Economic and Social Research Council, showed more than one in five adults and children were poor at the end of 2012.
They had a low income and were "multiply deprived" - suffering from three or more deprivations such as a lack of food, heating and clothing due to not having enough money.
About 28% of adults have skimped on their own food in the past year so others in their home could eat. Despite this, more than half a million children live in families who cannot afford to feed them properly.
Prof Bradshaw said: "The research has shown that in many households parents sacrifice their own welfare - going without adequate food, clothing or a social life - in order to try to protect their children from poverty and deprivation."
In 93% of households where children suffered from food deprivation, at least one adult "sometimes" or "often" went without food to ensure others had enough to eat.
Women were more likely to cut back than men, with 44% curbing four or more items such as food, clothes and social visits in the last 12 months, compared with 34% of men.
Research found wages are low and working conditions bad in many parts of the UK. One in six adults in paid work suffers from a low income and cannot afford basic necessities.
Full-time work is not sufficient to escape from poverty for a "large number of people", with almost half the employed poor working 40 hours a week or more.
Nick Bailey, from the University of Glasgow, said: "The UK Government continues to ignore the working poor; they do not have adequate policies to address this growing problem."
A Department for Work and Pensions spokesman said the report was painting a "misleading picture."
"The independent statistics are clear, there are 1.4 million fewer people in poverty since 1998, and under this Government we have successfully protected the poorest from falling behind with a reduction of 300,000 children living in relative income poverty and 100,000 fewer children in workless poor families.
"As part of our long-term economic plan, the Government is committed to tackling the root causes of child poverty."