What is food poisoning?
Food poisoning is an unpleasant illness which is caused by eating contaminated food. This includes food which has been poorly prepared, cooked at the wrong temperature or as a result of poor hygiene. It can also occur if raw food is stored next to cooked food.
This contamination includes bacteria, viruses, toxins or parasites.
This is a common illness which ranges from relatively mild through to serious, even life threatening conditions. The degree of severity of food poisoning will depend upon the cause.
Whatever the extent, food poisoning is a horrible illness which most of us have experienced at some point in our lives.
According to the Food Standards Agency (FSA) there are nearly 900, 000 cases of food poisoning each year. However, this figure may be higher due to the fact that not every case of food poisoning is reported.
(Source: NHS Choices: food poisoning)
So, food poisoning is more common than we realise.
Increase in the number of cases of food poisoning
Food poisoning is not only a common illness but one which appears to be on the increase.
Why is this?
There are two reasons for this:
- Changing lifestyles
- Global food market
Our lifestyles have changed over the last few years which include an increasing reliance on ready prepared meals, eating out rather than cooking and taking more holidays abroad.
We all lead busy lives and as a result of that tend to spend less time preparing and cooking food. People often cook several meals in advance and freeze them for a long period of time or buy convenience food which only has to be put in a microwave oven.
Another popular option is buying takeaway meals. It is a quick option with the minimum of fuss and offers a wide variety of choice.
But with this increased choice and flexibility comes an increase in health risks. Food poisoning occurs if food is not stored in the refrigerator at the correct temperature or is kept past its ‘sell by’date. Another problem is when food is reheated even though it is not designed to be or is not cooked for the right amount of time.
This applies to food bought for consumption at home, from a local fast food outlet or a restaurant.
Another factor is that women as well as men go out to work which means that they have less time (and inclination!) to cook a meal. At one time the woman stayed at home and had a meal ready for her family once they arrived home from work and school but that is less common nowadays.
If you are tired after a long day at work then the last thing you want to do is to spend hours preparing a meal when it is so much easier to put something in the microwave.
This combined with the fact that cookery is not as widely taught as it used to be has led to a decrease in basic cooking skills.
However, there has been a swing back to what are considered old fashioned cooking skills which is largely due to the current economic climate. People are having to cut back and are looking at ways of reducing their outgoings which often includes staying in and cooking rather than eating out or buying ready made meals.
This may reduce the number of food poisoning cases.
Global food market
Another reason is our ‘global village’: we are able to access a greater range of foods than before which are flown in from all parts of the world.
But these foods are often from countries which have different standards of food safety from the UK which means that it is easy for bacteria to quickly spread from one host to another.
Many of us have become accustomed to purchasing foods ‘out of season’, for example strawberries which be bought in winter rather than the summer. We expect to walk into a supermarket and purchase these foods whenever we want and don’t always give this a second thought.
But whilst it is ideal to have a wide range of choice there is an increased risk of contracting food poisoning due to variable food standards.
However there is a trend towards buying locally produced food or foods which are in season which might help alleviate this problem. Plus this also supports local growers which is beneficial for the economy.
Knowing where your food is sourced from and the standards of care and safety that have been applied may help to reduce the incidences of food poisoning.
What causes food to become contaminated?
Many cases of food poisoning can be attributed to poor food hygiene. Food which has not been properly prepared, cooked or stored becomes a ripe breeding ground for bacteria which multiply and then release toxins which are absorbed by the body.
These toxins cause the characteristic symptoms of food poisoning which are nausea, stomach pains, vomiting and diarrhoea. These symptoms develop quickly, often within 48 hours.
This is discussed in more detail in our bacterial food poisoning section.
Contamination and cross-contamination are the two main causes of food poisoning. Both of these are discussed in greater detail in our causes of food poisoning section.
Food can also be contaminated by viruses and pesticides. Viruses, for example norovirus are known for causing food poisoning, especially in areas where large numbers of people congregate, e.g. on board a cruise ship.
Find out more in our viral food poisoning section.
Pesticides are substances sprayed onto crops to protect them against pests, for example insects or weeds. However, there are risks to health from using these which includes symptoms of food poisoning.
Find out more in our toxins section of this guide.
To summarise: most but not all cases of food poisoning are caused by infected food. However, food poisoning can be caused by viruses spread by person to person contact or close proximity to an infected animal.
Food poisoning also occurs from drinking water which has been infected with bacteria or parasites such as giardia.
So whilst contaminated food is the most likely cause of food poisoning, do not discount the possibility of it being caused by a virus, parasite or toxin.
Food Poisoning Guide
- Food Poisoning
- What is food poisoning?
- Food poisoning or gastroenteritis?
- High risk for food poisoning
- Foods which are likely to cause food poisoning
- Types of food poisoning
- Chicken food poisoning
- Beef food poisoning
- Pork food poisoning
- Fish food poisoning
- Ciguatera poisoning
- Scombroid poisoning
- Bacterial food poisoning
- E coli
- Staphylococcus aureus
- Clostridium botulinum
- Campylobacter jejuni
- Vibrio parahaemolyticus
- Vibrio cholerae
- Bacillus cereus
- Clostridium perfringens
- Yersinia Enterocolitica
- Enterobacter sakazakii
- Viral food poisoning
- Entamoeba histolytica
- Mushroom toxins
- Red kidney bean toxins
- Shellfish toxins
- Causes of food poisoning
- Symptoms of food poisoning
- Diagnosing food poisoning
- Treatment for food poisoning
- Home based treatment
- Medical treatment
- Follow up treatment
- Complications of food poisoning
- Lactose intolerance
- Irritable bowel syndrome
- Kidney failure
- Haemolytic uraemic syndrome
- Reactive arthritis
- Guillain-Barre syndrome
- Reporting food poisoning
- Preventing food poisoning
- Cross contamination
- Food irradiation
- Food safety and your family
- Pregnancy and food poisoning
- Babies and food poisoning
- Children and food poisoning
- Teenagers and food poisoning
- Elderly and food poisoning
- Research into food poisoning
- Food Poisoning FAQs