Was it the reheated leftovers from three – or was it four or five – days ago? Or the sandwich you bought one day from that café you thought looked a bit dirty? Or maybe it was the salad that spent too long out of the fridge? Whatever the culprit, chances are you’ve been affected by food poisoning at some point in your life.
Food poisoning affects an estimated 4.1 million people in Australia every year. The symptoms of food poisoning can range from mild to severe, but there are steps you can take to reduce your risk, says Jean Hailes dietitian Stephanie Pirotta.
Food poisoning is caused by bacteria, toxins or viruses present in the food or drinks we consume. In Australia, food poisoning is commonly due to bacteria, namely the Campylobacter or Salmonella bacteria types.
However, as Ms Pirotta explains, not all bacteria are bad for you; some bacteria in food is normal – and in some cases, such as the good bacteria found in yoghurts, it can even be beneficial.
“Bacteria becomes a problem and can cause food poisoning when they grow to unsafe levels, or if the type of bacteria present in the food is harmful,” says Ms Pirotta.
Symptoms of food poisoning may include nausea (feeling sick), vomiting, stomach pains, diarrhoea (loose watery bowel motions), feeling weak, headache, fever, chills or sweating. When the symptoms start, how long they last and how serious they are can depend on many factors.
A common assumption is that food poisoning is caused by the last thing the person ate. However, this is often not the case, says Ms Pirotta. “Symptoms of the bacteria Campylobacter food poisoningusually develop two to five days after eating the food,” she says. And which food is usually the guilty party in cases of Campylobacter? “This type of illness is frequently associated with eating undercooked chicken,” says Ms Pirotta.
So how can you best protect yourself? Below Ms Pirotta answers some frequently asked questions.
Many people know that chicken or fish are common sources of food poisoning, but there are other common foods that can be potentially dangerous. Sources of food poisoning will usually look, smell and taste normal, so in this way it can be hard to detect.
Some potentially high-risk foods include:
This is the temperature range in which harmful bacteria can grow to unsafe levels in food. The danger zone is between 5⁰C and 60⁰C.
This means it is best to keep cold foods cold – in your fridge, set below 5⁰C – and hot food should be kept and served hot – at 60°C or hotter. Using a food thermometer is an easy way to measure food temperature. These can be bought at most supermarkets.
For freshly cooked food that you’re not going to eat straight away, the Australian Food Safety Information Council advises to cool them to below the danger zone as quickly as possible: divide food into small shallow containers and place in the fridge or freezer as soon as it stops steaming.
The ‘2 hour/4 hour rule’ tells you how long potentially high risk foods can be safely held at temperatures in the danger zone – for example leaving the food outside the fridge, after cooking or at the table.
Many people are unaware that cooked rice, when improperly stored, is a common source of food poisoning. Cooked rice is a perfect growing ground for bacteria as it is moist, full of carbohydrates for energy and provides heat. Rice grains often contain the bacteria Bacillus cereus. These bacteria can form spores that are able to survive the high temperatures of cooking. If uneaten rice is cooled slowly and left in the temperature danger zone for too long, tiny spores can grow and produce a harmful toxin (poison).
This also means reheating the cooked rice does not kill the spores or destroy the toxins that have already been produced in the rice, so they can still make you ill.
Food poisoning symptoms from this bacteria and its toxins usually consists of vomiting and/or diarrhoea for up to 24 hours.