There may be days when you are too tired to prepare and cook a meal and would prefer to go for a cheaper or quicker alternative. If you are cooking in batches or eating leftover food, it's important to know basic hygiene rules to reduce the risk of harmful bacteria. This is especially important when you're cooking for someone whose immune system is lowered.
Cooking at home
Never risk using food that is out of date because you don't want to waste money. People who are having treatment for cancer (are neutropenic) are advised to avoid foods that have a higher chance of being contaminated with Listeria monocytogenes, which includes pre-packed sandwiches, unwashed salad, raw vegetables or fruit, soft blue cheeses, deli meats, smoked salmon or pate. For information on preventing listeriosis visit the NHS website.
If you aim is to save money by cooking food in bulk, make sure you defrost meals properly before reheating them until they're piping hot. Leftovers are great for saving money, but make sure you cool them as quickly as possible, put them in the fridge and eat them within 24 hours of defrosting. Follow guidelines for freezing and defrosting food at NHS Choices.
Takeaway food, soft cheeses, raw or lightly cooked eggs, shellfish or liver pate may contain harmful bacteria and are best avoided. Aditionally, it's important to make sure that any food you buy is pasteurised as this kills harmful bacteria including Salmonella, E. coli and Listeria, that could be harmful to you if you have a weakened immune system (or are pregnant).
Unpasteurised products include milk, cheese, dairy and fruit juices (freshly-squeezed fruit juices should be avoided). On the whole, most foods you will buy from supermarkets will be pasteurised, but if they are from local farms or you are eating out, it's always worth asking just to be on the safe side.
Depending on the type of cancer and treatment, some diet guidelines may be stricter than others. If you're unsure always ask your doctor or dietitian for advice.
Best before and use by dates
Use by dates
By understanding food labels, you and you could end up saving money by not having to throw out food that is actually safe to eat.
Always check the use by date on foods before eating them. If food is eaten past this date (even if it looks and smells okay) it could be very dangerous, especially if your child is neutropenic.
If you haven't got time to eat something before it goes off, check the packaging to make sure it's suitable for freezing.
Best before dates
Best before dates are different because unlike use by dates (which appear on foods that can go off quickly) these dates give you an idea of how long the food will be at its best quality.
They will also generally have a longer shelf-life. This means that if you use foods after this date, it isn't necessarily unsafe.
Other storage instructions
Just to confuse matters even more, you will also see things like 'eat within three days' or 'refrigerate once opened'. The use by date will still apply on these products. This means that if it says you should use it by the end of the following day, you can't then use it for three days.
Display by or sell until dates may also appear on some of your foods and are information for the shops, but don't necessarily mean they are out of date.
If you are unsure about any food then the best thing to do is to avoid it completely.
Updated July 2016, next review due 2017.