Many adults are ignoring use-by dates on food amid confusion about labelling or a preference for the “smell test”, putting themselves at risk of serious illness, a regulator has warned.

The Food Standards Agency (FSA) found 50% of adults in England, Wales and Northern Ireland do not always check the use-by date.

Three quarters (76%) have knowingly eaten food past its safe time limit and 37% admit to cooking food for other people that is past its use-by date.

The poll suggests consumers are confusing use-by dates with best before dates, which is a quality indicator that food eaten beyond this time might not taste as good.

Half of adults (50%) cannot correctly define the use-by date as the date up to when food can be eaten safely.

Some 44% view them as a “useful guide” without realising the potential health risks of getting food poisoning.

More than three quarters of adults (77%) decide whether food is safe to eat by smelling it, which rises to 80% of women compared with 73% of men.

A quarter of men (26%) have sniffed cooked chicken past its use-by date and eaten it based on the smell.

FSA chief scientific adviser Professor Robin May said: “These findings are worrying. They indicate that people are often confused about food dates, potentially putting themselves and others at risk of illness.

“A use-by date on food is there for a reason. It is about safety.

“After the use-by date you should not cook, freeze or eat the food, even if it smells or looks okay. It’s really not possible to tell whether food is safe to eat by smelling or tasting it. We would like everyone to take the use-by dates on their food seriously.”

He added: “It’s great that consumers are trying to minimise food waste, but there are lots of ways to do that without gambling with your health, such as planning your meals ahead of time, checking what you have in the fridge that’s close to its use-by date and freezing food right up until the use-by date.”

Ipsos Mori surveyed 2,132 adults in England, Wales and Northern Ireland in March.

A spokeswoman for the FSA said: “There are around 2.4 million cases of food poisoning each year and unfortunately around 180 people die each year.

“For a large proportion of cases of illness, it is very difficult to attribute the exact food that has caused the illness.

“We know a lot of cases of food poising arise from food prepared in the home, which emphasises how important it is to check dates on labels and follow good food hygiene practices when cooking for you or your family.

“Although the likelihood of becoming unwell due to of date food is relatively low, if you do get unwell it could be very serious and you could even be hospitalised.”

She said food poisoning can be particularly dangerous if it is experienced by people in at-risk groups, such as elderly people, children, or those with an underlying health condition.