Food safety experts are cautioning that indulging in Christmas leftovers after Boxing Day could pose serious health risks.

For those in the UK hoping to enjoy their leftover holiday meals, it’s recommended to consume them within a couple of days—only if they’ve been stored in the fridge or freezer inside two hours of being served.

The Food Standards Agency (FSA) warns that leaving Christmas dinner leftovers out for over two hours, or consuming food that hasn’t been chilled, significantly raises the risk of food poisoning.

The danger lies in the potential for harmful bacteria, such as salmonella and campylobacter, to multiply swiftly, leading to unpleasant symptoms like diarrhea, nausea, and vomiting.

In its updated holiday advice, the FSA emphasized the importance of adhering to use-by dates and advised against leaving buffet items out for longer than four hours.

The agency stated, “Use-by dates are about safety, not quality. Avoid consuming food past its use-by date.”

The guidance added, ‘Keep it cold. Buffet food shouldn’t sit out for more than four hours.’  

It was one of 11 common mistakes the FSA highlighted which has the potential to ‘ruin Christmas’. 

According to the FSA, keeping Christmas dinner remains for more than two days without proper refrigeration could make you seriously ill  

That turkey sandwich could make you seriously ill if the meat hasn’t been stored properly

‘Research reveals we’re a nation of festive food gamblers, with large numbers likely to take risky kitchen shortcuts that could leave themselves, family and friends seriously ill over the holidays,’ the FSA said. 

‘And for some people—like pregnant women, those with weakened immune systems and older people, the risks are even greater.’ 

Such mistakes include eating dairy products such as cheese, cream, milk and desserts past their use-by dates. 

This is risky as deadly bacteria like listeria – which can’t be seen, tasted or smelt – could be present. 

The same is true of smoked fish or cold meats, which have the potential become a bacterial breeding ground which could make people seriously ill. 

Other ‘festive food fails’ include not thawing poultry or meat properly. This can cause uneven cooking, stopping it from reaching safe temperatures throughout.

Reusing knives or utensils used for raw meat and other foods without cleaning thoroughly them first, may also pose a health hazard, the FSA said.   

Food poisoning can also occur because the fridge is too warm.

One in six fail to cool leftovers at room temperature before refrigerating, the FSA says

Food Standards Agency (FSA) officials say stuffing your turkey could increase the risk of food poisoning 

It advised to check the temperature remains below 5C, as bacteria thrives between 8C and 63C.

Cooked turkey can be frozen for up to six months, but once it is defrosted, it must be eaten within 24 hours and cannot be re-frozen, the FSA advised.

Around 70,000 people in England and Wales seek medical advice for food poisoning over the Christmas period, stats suggest.

But the FSA believes the figure could be as high as 2.4million, as many do not go to the doctor.

The agency also reminded hosts to check in with their guests for any allergies or intolerances a few days before hosting, to give them ample time to prepare, and avoid any life-threatening allergic reactions.  

Nearly a third of Britons fail to ask their guests about dietary requirements, increasing the risk of a variety of symptoms, with anaphylaxis being the most severe reaction, the FSA said. 

This can make it hard or even impossible to breathe and can cause the body to go into a cardiac emergency like cardiac arrest due to a lack of oxygen.