How to use leftovers safely

Rising shopping bills have led to some people ignoring basic food safety advice in a bid to save money and make their meals go further, according to a survey.

More than 30% of the 1,900 people who took part in the survey admitted to ignoring "use by" dates and relying on “smell and look” when deciding if food was safe to eat.

The survey was commissioned by the Food Standards Agency (FSA) to highlight the growing concern over food poisoning caused by food leftovers.

A food label’s "use by" date is the most important guide to whether food is still safe to eat because many harmful germs are odourless and therefore impossible to detect.

“It’s tempting just to give your food a sniff to see if you think it’s gone ‘off’,” says Bob Martin, a food safety expert at the FSA.

“But food bugs like E. coli and salmonella don’t cause food to smell off, even when they may have grown to dangerous levels. So food could look and smell fine but still be harmful.”

'Best before' and 'use by':

  • Food with a "use by" date goes off quite quickly. It can be dangerous to eat after this date.
  • Food with a "best before" date is longer-lasting. It should be safe to eat but may not be at its best quality after this date.

There are around one million cases of food poisoning every year in the UK, with an extra 120,000 cases occurring between June and August.

One of the reasons for the summer surge is warmer temperatures causing any germs present to grow faster.

Safety tips

The FSA has drawn up a list of tips on storing leftovers safely to help your food budget go further.

Plan ahead

  • Don’t just make a shopping list – plan your meals too.
  • Check what’s in your fridge before shopping so you eat food you’ve already got before its "use by" date.

When you’re shopping

  • Check "use by" dates when buying food to make sure you’ll use it in time.
  • Be careful with special offers such as "3 for 2". You might end up with too much food to eat before its "use by" date.
  • Before taking advantage of special offers, check whether you can freeze the extra pack or cook double the amount and freeze some to use later. 

Love leftovers

  • Don’t throw out your leftovers: they can be tomorrow’s lunch.
  • Cool leftovers as quickly as possible, ideally within 90 minutes (splitting into smaller portions can help). Then cover and refrigerate.
  • Use leftovers within two days and reheat till steaming hot.
  • Don’t reheat leftovers more than once. 

Can reheating rice cause food poisoning?

The fridge and freezer

You may be able to freeze food up until its "use by" date.

  • Check the packaging to see if it’s suitable for freezing.
  • Freeze your leftovers. Wait until they’ve cooled before you put them in the freezer.
  • Always defrost leftovers completely, either in the fridge or in the microwave.
  • Cook the food within 24 hours of defrosting until steaming hot and do not refreeze.
  • Make sure your fridge temperature is below 5C.

Costly savings

“With most of us seeing our weekly shopping bills increase over the last few years, we are all looking for ways to get the most out of our shopping budget,” says Martin.

“Using leftover food is a good way of making our meals go further. However, unless we’re careful, there’s a chance we can risk food poisoning by not storing or handling them properly.”

Families could save up to £50 a month by reducing the amount of food and drink they throw away. 

“Making the most of the food we buy is increasingly important to us all, especially with ever tighter household budgets,” says Emma Marsh, from the Love Food Hate Waste campaign. 

“But we’re still unnecessarily wasting 20% of the food we buy. Food is there to be eaten, so this Food Safety Week let’s enjoy our leftovers and do it safely.” has hundreds of tips, recipe ideas and inspiration to help everyone waste less and save more.

Page last reviewed: 11/06/2014

Next review due: 11/06/2017


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