Some foods can cause food poisoning if they're contaminated with certain bugs.
While most healthy people recover from food poisoning without treatment, you're especially vulnerable to a bout of severe (even life-threatening) food poisoning if you're over 65 because your immune system isn't as strong as that of someone younger and it's harder for your body to fight off germs.
Food poisoning isn't just a nuisance. The symptoms in people over 65 are often worse than in younger people, and can lead to dangerous complications such as dehydration.
Older people can also take longer to recover from food poisoning.
If you have symptoms of food poisoning seek medical help straight away.
Here are foods to be careful with:
(This advice also applies to anyone with a weakened immune system, including people with an underlying health condition, pregnant women and babies and young children.)
Some soft cheeses
It's best to avoid eating mould-ripened soft cheese, such as brie and camembert along with soft blue cheeses, such as danish blue, gorgonzola and roquefort, and any unpasteurised soft cheeses.
These cheeses can be risky to eat when you're older because they may be less acidic and contain more moisture than hard cheeses, which makes them an ideal environment for food-poisoning bugs, particularly listeria, to grow in. Cooked soft cheeses are fine because heat kills this bacteria.
Try to steer clear of all types of fresh or chilled pâté, including vegetable pâtés, as they can contain listeria. Tinned pâté should be harmless as it will have gone through a heat treatment as part of the canning process.
Raw or runny eggs
Eggs produced under the British Lion Code of Practice are safe to eat raw or partially cooked (runny). These eggs have a red lion logo stamped on their shell.
However, people who have a weakened immune system and are on special diets should cook eggs thoroughly (until the whites and yolks are solid).
Avoid any eggs not produced under the lion code if they are raw or undercooked, and any foods that contain them, such as homemade mayonnaise and hollandaise sauce. This is because they increase your risk of salmonella food poisoning.
Make sure eggs without the lion code are thoroughly cooked until the whites and yolks are solid.
Duck eggs, quail eggs and goose eggs should be cooked until the whites and yolk are solid.
Many cold meats such as salami, prosciutto, chorizo and pepperoni are not cooked, just cured and fermented, so there's a risk that they contain toxoplasmosis-causing parasites. It's best to check the instructions on the pack to see whether the product is ready-to-eat or needs cooking first.
For ready-to-eat meats, you can reduce any risk from parasites by freezing cured/fermented meats for four days at home before you eat them. Freezing kills most parasites and so makes the meat safer to eat.
If you're planning to cook the meat (for instance, pepperoni on pizza) then you don't need to freeze it first.
If you're eating out in a restaurant that sells cold cured/fermented meats they may not have been frozen. If you're concerned, ask the staff or avoid eating it.
Raw or undercooked meat and poultry
Be careful at barbecues. Rare or undercooked meat – especially poultry, sausages and burgers – can harbour food poisoning bugs such as salmonella, campylobacter and E.coli.
Make sure you cook meat or poultry thoroughly so there's no trace of pink or blood. And remember to wash your hands along with all kitchen surfaces and knives after preparing raw meat or poultry to prevent spreading any harmful bugs.
Read why you should never wash chicken plus lots of other kitchen hygiene tips.
Hold the oysters! Raw shellfish (such as mussels, lobster, crab, prawns, scallops and clams) can contain harmful bacteria and viruses that can trigger food poisoning.
Cooked shellfish is safe, as are cold pre-cooked prawns.
Sushi and other dishes made with raw fish are fine as long as the fish has been frozen first. This is because fish occasionally contains small parasitic worms that can make you ill, but freezing kills the worms and makes raw fish safe to eat.
Sushi sold in shops is generally "bought in" and therefore safe to eat because it will have been previously frozen appropriately.
If you make your own sushi at home, freeze the fish for at least four days before using it.
Don't drink raw (unpasteurised) milk. Instead, stick to pasteurised or UHT (ultra-heat treated) milk – sometimes also called long-life milk.
In reality, all the milk sold in shops and supermarkets will be pasteurised or UHT; you can only buy unpasteurised milk direct from farms, farm shops and at registered farmers' markets.
Beware of raw or lightly cooked bean sprouts as they're a potential source of food poisoning.
The warm, moist conditions required to grow sprouts are ideal for the rapid growth of bacteria. So make sure to cook all sprouted seeds thoroughly until they're steaming hot throughout before eating them.
Read more sprouted seeds safety advice.
Read more about how to avoid food poisoning.