Homes across Britain are wasting a total of 3.3m tonnes of food a year, a report is expected to reveal.
Most wasted food ends up on landfill sites
The study, by the government's waste body Wrap, will say households dump just under a third of all the food they buy, although half is inedible waste.
Most of the waste food goes into landfill sites, where it breaks down and causes greenhouse gases.
The inedible items include teabags and bones. But it still means more than 15p of each £1 spent on food is wasted.
Focusing on combating climate change, the report will remind people that about one-fifth of our carbon emissions are related to the production, processing, transport and storage of food.
Wrap's chief executive Jennie Price told BBC Radio 4's Today programme there were lots of things people could do to prevent wasting food.
"Just simple things like looking in the fridge, looking in the cupboard, before you go shopping.
"Seeing 'I've got a lettuce, that's fine, I don't need another one'."
Wrap also asked 1,800 people about their attitudes to waste - with just 10% believing they throw away a substantial amount of food.
The organisation said the survey suggested people were in a state of denial about the amount of food they were wasting.
Tim Lang, professor of food policy at City University, London, described Britain as a "throwaway food society" in which people gave no thought to wasting food.
Instead people should adopt an "ecological and nutritionalist" culture in which they considered the environmental consequences of filling up landfill sites with their waste food.
"We are getting the ecological consequences of a consumerist culture," Prof Lang told Today.
He added: "A third of people are throwing away food that's cooked and left on the plate. This is just ridiculous. This is a society that misjudges food; this is a society that doesn't value food."
The Wrap report came as government-commissioned research found that fortnightly rubbish collections need not create health hazards, bringing the end of the weekly pick-up a step closer.
Look in your fridge to see what you need to buy, says Wrap
Food writer and broadcaster Marguerite Patten was a food adviser to the government during World War II.
She said attitudes had changed since the war years when it was a crime to waste food.
Ms Patten also said that as a widow of 10 years she found it much harder to buy food for one.
Independent retail consultant Teresa Wickham said part of the reason for the increase in waste was that people were buying more fresh produce, which had a shorter shelf life.
She added: "It's much more down to lifestyle and the fact that we have a huge choice and we're not the best at doing things with leftovers."
Ministers are keen to reduce waste as part of their attempts to combat climate change, as landfill sites produce a lot of methane - a powerful greenhouse gas.
Wrap said it was becoming too easy to buy lots of food, and has called on supermarkets not to encourage consumers to buy too much.
Among the problems Wrap identified were people keeping food in fridges which were too warm, allowing food to go out of date as well as catering for fussy children.
Other causes may be that ready meals are the wrong size, that food gets put into the back of the fridge or that we may not feel like eating it after buying it.