Christians Against Poverty said just under a third of the UK's population were eating less healthily than last year as soaring food prices and the ongoing financial crisis forces people to make cuts in their spending.
A YouGov poll commissioned by CAP found that 32 per cent of the 2,000 respondents had turned to cheap, processed foods in a bid to save money.
The survey also found that more than half - 53 per cent - of the UK's population believe their finances are now in a worse state than this time last year with one in five of those respondents saying they were much worse.
The financial crisis threatens to derail government efforts to improve the nation's diet with nearly half of all 35 to 44-year-olds confessing that their diet had deteriorated in the last twelve months.
CAP has responded to the findings by issuing its top ten tips on how to cut back on food costs whilst maintaining a healthy diet. The charity has also posted recipes that can feed a family of four for £4 on its website.
The poll also found discrepancies between the North-South divide and different age groups, revealing that those below the age of 25 feel more positive about their finances than those over the age of 45. Whilst nearly 60 per cent of 45 to 54-year-olds felt they were in a worse financial state than last year, only 41 per cent of 18 to 24-year-olds felt the same way.
In the North, nearly 60 per cent of people felt their finances had worsened in the past 12 months, compared with London where the figure fell to less than half, or 48 per cent.
Nearly half of all the 2,057 respondents - 48 per cent - stated that they had not let food price increases affect their diet, but admitted that their budgets had been really stretched to get around the price hike.
CAP said it was worried that these people would soon be forced to make changes for the worse to their diet in order to avoid falling into debt if food and fuel prices continue to rise.
Matt Barlow, head of Christians Against Poverty UK, said: "These results are truly shocking and evidence that we are slipping further into financial difficulty as a country.
"However, whilst many would concentrate solely on the impending crisis, we want to underline how there is a solution for those trapped by debt in the UK.
"Through our national network of 82 church-based debt counselling centres, we are seeing people turn their finances around from Aberdeen down to Penzance, evidence too that with the right support, guidance and sound financial principles, people can avoid the worst excesses of this economic downturn and work their way out of debt."
On the web: www.capuk.org
