If you have ever felt ill after consuming some food, there is a high chance what you experienced was food poisoning.

Also known as foodborne illness, food poisoning refers to any illness that is caused by consuming spoilt, toxic or contaminated food.

Most cases of food poisoning result from food being contaminated by various types of bacteria or a virus.

Thankfully, food poisoning is not life-threatening.

In most cases, the symptoms go away by themselves after a few days without the need for medical attention.

Food poisoning is quite common.

The Centers for Disease Control and Prevention (CDC) estimates that 48 million Americans are affected by food poisoning every year.

Of these, only about 128,000 of them get hospitalized, and only about 3,000 people die of foodborne illnesses in a year.

Cases of food poisoning are more common among infants and children, the aged, and people with weak immune systems, such as those suffering from HIV or other chronic illnesses.


In most cases, the signs and symptoms of food poisoning will be experienced within a day or two after consuming contaminated food.

Depending on the cause of contamination, however, some symptoms may be experienced within a few hours, while others might appear after a few weeks.

If you have food poisoning, you might experience any of the following symptoms:

  • Diarrhea, which might be bloody or contain some mucus
  • A fever
  • Vomiting
  • Nausea
  • Chills
  • Aching within the muscles and joints
  • Stomach cramps and pain in the abdomen
  • Loss of appetite
  • General weakness and fatigue
  • Headaches


In most cases, someone suffering from food poisoning will get better without the need to see a doctor.

However, you should seek medical attention immediately if you notice any of the following symptoms:

  • The symptoms become very severe
  • Your diarrhea and other symptoms do not get better after about 3 days.
  • Constant vomiting makes it difficult for you to keep down any fluids.
  • You are above the age of 60
  • You’re pregnant.
  • If the person with food poisoning is a baby
  • Your fever exceeds 101.5°F.
  • You start experiencing symptoms that are associated with severe dehydration, such as passing little or no urine, confusion, a dry mouth, sunken eyes, and a rapid heartbeat.
  • You pass bloody urine.
  • You are taking medication or have a condition that may weaken your immune system, such as HIV or undergoing cancer treatment.
  • You have an underlying long term illness, such as kidney disease, diabetes, heart valve disease or inflammatory bowel disease.
  • You start having difficulty speaking or seeing.


Most of the foods that we eat have bacteria, parasites, and viruses that are potentially harmful if they find a way into our system.

This is why it is recommended that all foods should be cooked before eating.

The harmful pathogens are killed by the heat during the cooking process. This is why a lot of food poisoning is caused by foods that are eaten raw.

Some of the reasons and methods through which food might become contaminated include:

  • Food, especially meat, not getting cooked thoroughly.
  • Food that needs to be chilled not being stored in the right conditions.
  • Food being kept beyond its expiry date.
  • Cooked food being left for long at warm temperatures.
  • Food getting handled by someone with dirty hands or someone who is ill.
  • Previously cooked food not getting reheated sufficiently.
  • Bacteria spreading from contaminated food and surfaces to uncontaminated food (cross-contamination).

Some foods are more likely to be contaminated than others, particularly if they are not cooked or stored properly.

Examples of such foods include:

  • Unpasteurized milk
  • Raw eggs
  • Raw meat and poultry
  • Raw seafood
  • Foods that don’t need to be cooked before eating

We saw earlier that food can be contaminated by different pathogens.

There are over 250 different pathogens that might be behind food poisoning.

Some of the most common types of food contamination include:

Salmonella: Most cases of serious food poisoning in the United States can be attributed to the Salmonella bacteria.

According to the CDC, the salmonella bacteria is responsible for about 1 million cases of food poisoning every year, with about 23,000 of these ending up being hospitalized.

About 450 deaths can be attributed to Salmonella each year. Salmonella is usually found in raw eggs, raw meat and poultry, milk, and other dairy products.

Infection can occur when meat or poultry is not adequately cooked.

Salmonella can also be spread to other foods by cutting surfaces, knives, or handling of food by an infected person.

The symptoms of salmonella food poisoning start appearing 12 to 72 hours after consuming the infected food. In most cases, the symptoms will subside in about 4 to 7 days, even without treatment.

Campylobacter: This is a bacteria that is mostly found in meat and poultry. It is most likely to infect you if you consume undercooked meat.

Campylobacter contamination usually occurs when animal feces come into contact with meat surfaces during processing.

Campylobacter can also be found in contaminated water and unpasteurized milk.

If you consume food that is contaminated with campylobacter, the symptoms will appear in about two to five days and will be gone in about a week or less.

Listeria: This bacteria is mostly found in chilled, ready to eat foods, such as hot dogs, cooked meat slices, pre-packed sandwiches, and unpasteurized milk and cheeses. Listeria can also be found in unwashed raw produce.

Following consumption of food that is contaminated with listeria, the appearance of symptoms will vary from person to person.

They can appear in a few days or after several weeks. In most cases, the person will feel better in about 3 days.

However, food poisoning from listeria can be more serious in pregnant women. It can result in pregnancy and birth complications, and in extreme cases, it can lead to miscarriage.

Escherichia coli (E. coli): This is a common bacteria that lives in the digestive tracts of various animals. It is even found in humans.

While most strains of E. coli are harmless, some can lead to serious cases of food poisoning.

Most cases of E. coli food poisoning are caused by eating undercooked minced beef, as well as other beef products like meatballs and burgers.

Beef usually gets contaminated during the slaughter process when fecal matter comes into contact with the meat. E. coli can also be found in unpasteurized milk products, contaminated water, alfalfa sprouts, and apple cider.

The symptoms of E. coli food poisoning start appearing between one and eight days after infection. The person will feel better after a few days or weeks.

Shigella: Shigella is spread when food is washed in contaminated water. Food poisoning caused by the Shigella bacteria is referred to as shigellosis or bacillary dysentery.

The symptoms of food poisoning caused by shigella appear within a week of consuming contaminated food and will usually disappear in less than a week.

Viruses: Viruses can also cause food poisoning. The most common culprit in this case is a virus known as Norwalk virus or simply novirus.

Over 19 million cases of food poisoning can be attributed to novirus every year. This virus is mostly spread through contaminated water and from person to person.

It is also commonly found in raw shellfish. Novirus food poisoning is usually mild and not life threatening, though it can be fatal in rare cases.

Symptoms will usually appear within 24 to 48 hours of consuming the contaminated food and will only last a couple days.

Other viruses that may cause food poisoning are sapovirus, astrovirus, and rotavirus, though they are not as common.

Rotavirus mostly causes food poisoning in children, with the symptoms appearing in about a week and lasting 5 to 7 days.

The Hepatitis A virus can also be passed through food, causing a very serious illness.

Parasites: Food poisoning as a result of contamination by parasites is a bit rare, though the cases are common in developing countries.

While rare, food poisoning caused by parasites can be very dangerous.

A person will start feeling ill in about 10 days after consuming contaminated food, and if left untreated, it may be weeks or months before the symptoms disappear.

The most common culprit in cases of parasite caused food poisoning are is toxoplasma, which is usually found in cat litter boxes.

This parasite can also remain undetected in the human digestive tract for years.

Pregnant women and people with weakened immunity system are at the greatest risk of getting an infection due to toxoplasma.

Other common types of food poisoning caused by parasites include amoebiasis, which is a type of dysentery caused by Entamoeba histolytica, cryptosporidiosis, which is caused by Cryptosporidium, and giardiasis, which is caused by Giardia intestinalis.


In most cases, tests are not necessary for the diagnosis of food poisoning.

Instead, the doctor will ask questions about the specific foods you have consumed recently, the symptoms you are experiencing and for how long you have been feeling sick.

The doctor might also examine you physically to determine whether you are showing any signs of dehydration.

In some cases, depending on your health history and the symptoms you are experiencing, the doctor might need to run some diagnostic tests to determine the cause of the food poisoning.

The most common tests for parasites include blood tests and stool culture tests.

However, not every case of food poisoning can be confirmed using diagnostic tests.


Thankfully, most cases of food poisoning are not very serious and can be treated at home without the need to seek medical attention.

The symptoms will usually resolve by themselves after a few days.

Due to vomiting and diarrhea, someone who has food poisoning rapidly loses water, so it is important to keep drinking plenty of water to avoid dehydration.

Even if you don’t feel like drinking water, taking a few sips every now and then will help keep you hydrated. Alternatively, you can drink sports drinks which are high in electrolytes.

Coconut water and fruit juices are also great for people with food poisoning.

Not only do they keep you hydrated, they also provide your body with carbohydrates and help reduce fatigue and weakness.

For people who are highly vulnerable, such as the elderly and those with underlying medical conditions, oral rehydration solutions are recommended.

These are sold at pharmacies in form of sachets. The sick person can then dissolve them in water and drink.

Oral rehydration solutions are great for helping replace glucose, minerals and salts that have been lost through dehydration.

However, oral rehydration solutions may not bode well for some people, such as those with kidney conditions.

Therefore, it is always advisable to consult your doctor or pharmacist before using oral rehydration solutions.

In addition to keeping yourself hydrated, you should also get plenty of rest and avoid substances like caffeine, fizzy drinks, alcohol, and fatty or spicy foods.

These will irritate the digestive tract and make you feel worse. Instead, opt for decaffeinated teas with soothing herbs such as dandelion, peppermint or chamomile, since these can help sooth an upset stomach.

You can also use over-the-counter medications such as Pepto-Bismol and Imodium to help reduce the nausea and diarrhea.

Before using these medications, however, it is advisable to consult your doctor, since diarrhea and vomiting helps the body to get rid of the toxins causing the illness.

Using these medications can also make the illness seem less severe, making you wait longer without seeking medical attention even when the illness is severe.

Once you feel up to it, ease back into eating with small, light and easy to digest foods that are bland and low in fat.

Wait until the diarrhea and vomiting has subsided before you start eating solid foods. The best foods to eat in this case include:

  • Saltine crackers
  • Bananas
  • Toast
  • Rice
  • Chicken broth
  • Oatmeal
  • Boiled veggies
  • Bland potatoes
  • Gelatin
  • Decaffeinated soda, such as root beer or ginger ale
  • Sports drinks
  • Diluted fruit juices

Until you are completely healed, you should avoid harder to digest foods, since they might upset your stomach even more.

The foods to avoid include:

  • Fried foods
  • Spicy foods
  • Dairy products such as milk and cheese
  • Foods with high sugar content
  • Highly seasoned foods
  • Fatty foods
  • Energy drinks

If you feel that your symptoms are severe, or if you don’t start getting better after a few days, you should see a doctor.

You should also see a doctor if you have an underlying medical condition that makes you more vulnerable to serious infection, or if you are over 60 years of age.

If your vomiting is too severe, the doctor might prescribe anti-emetic medications to help stop the vomiting.

If the doctor determines that your food poisoning is as a result of a bacterial infection, he or she may prescribe antibiotics to help get rid of the bacteria.

If the illness is deemed to be too serious, the doctor might require you to be admitted to hospital for a couple days so that you can be hydrated with intravenous (IV) fluids while the doctor monitors your recovery.


In most cases, any complications resulting from food poisoning are usually due to dehydration.

This is where the body loses too much water and essential minerals and salts through vomiting and diarrhea.

For health adults with no underlying medical conditions, staying hydrated until you get better is enough to prevent any complications from occurring.

Dehydration presents a more serious concern for infants, the elderly, people with chronic illnesses and people with conditions that might have weakened their immune systems.

In some cases, such people who are more vulnerable may need to be admitted so that they can receive intravenous rehydration. In extreme cases, dehydration can even lead to death.

Aside from dehydration, the other complications that might result from food poisoning depend on the kind of food poisoning and the infected person.

The types of food poisoning that may result in complications include:

Listeria food poisoning: Listeria food poisoning can result in complications for pregnant women.

If a pregnant woman gets food poisoning in the first trimester of the pregnancy, the illness may result in a miscarriage. If a pregnant woman gets listeria food poisoning later in the pregnancy, the infection may result in complications such as premature birth or still birth.

In the event that the baby is born normally, they baby might experience a potentially fatal listeria infection after birth.

Babies who survive this infection might experience delayed development and long-term neurological damage.

E. coli food poisoning: Food poisoning caused by some strains of E. coli might lead to a complication known as hemolytic uremic syndrome.

This is a condition that causes damage to the lining of the blood vessels within the kidneys.

In extreme cases, this syndrome can even result in kidney failure. Children below the age of 5, the elderly, and people with a condition that weakens their immune systems are most vulnerable to developing hemolytic uremic syndrome.

Someone in any of these groups should seek immediate medical attention should they have profuse or bloody diarrhea.


If you have food poisoning, you can easily spread the infection to those around you.

To avoid this, you should avoid handling or preparing food that will be consumed by other people.

You should also avoid getting into contact with people who are highly vulnerable, such as children under the age of 5 or the elderly. You should also avoid going to work or school until the diarrhea has stopped.

If the infected person is someone you live with, you should:

  • Make sure everyone uses their own flannels and towels.
  • Ensure that everyone washes their hands with warm water and soap before and after preparing food and after using the toilet.
  • Use the hottest washing machine setting to wash the laundry of the infected person.
  • Frequently clean taps, basins, toilet seats, flush handles, and the surfaces around your home.


Preventing food poisoning comes down to maintaining high standards of hygiene when handling, preparing and storing food.

According to the Food Standards Scotland, the key to preventing food poisoning is keeping in mind the “four Cs, which are:

Cleaning: Maintaining high standards of personal hygiene and keeping utensils and work surfaces clean can help prevent the spread of harmful pathogens that may cause food poisoning.

Make a habit of washing your hands with soap and warm water after handling raw food, before preparing food, after using the toilet, after touching pets and bins, and after changing a baby’s diaper.

You should also avoid handling food if you have food poisoning or other stomach illnesses. You should also thoroughly wash vegetables and fruits before consumption.

Cooking: All food, and meats, poultry and seafood in particular, should be thoroughly cooked to make sure any harmful bacteria in the food are killed.

To check whether meat is well cooked, dip a knife into the thickest part of the meat and make sure that there are no red or pink parts, and that all the juices in the meat are clear.

Proper care should also be taken when reheating food. Make sure that the food is well heated all through, and avoid reheating food more than once.

Chilling: If you have food that needs to be refrigerated, always keep it in the fridge and ensure that the temperature in your fridge is set between 0 – 5°C.

Leaving such food unrefrigerated can result in the growth and multiplication within the food. If you have cooked leftovers, allow them to cool over a couple of hours and then store them in the fridge.

Cross contamination: Sometimes, bacteria can be transferred from contaminated foods (especially raw foods) to other foods when the foods come into contact, when the bacteria is left on the utensils and work surfaces used in the preparation of food, or when one food drips onto another.

To prevent cross contamination, you should:

  • Store ready-to-eat foods separate from raw foods.
  • Use separate knives and cutting boards for meat, seafood, eggs, and poultry.
  • Store raw meat at the bottom of your fridge and inside sealable containers so that it does not drip on other foods.
  • Thoroughly clean any utensils that have been used in the preparation of raw food.
  • Avoid washing raw meats and poultry, since this might splash harmful bacteria all over your kitchen. Any bacteria on the meat will be killed during the cooking process.
  • Wash your hands with soap after handling raw food.

Aside from the four Cs, also make sure never to consume any food that is past its “use by” date.

Never rely on the food’s smell or appearance to determine whether it is safe to eat.

Always observe the instructions on the packet.


Food poisoning is a common illness that occurs after consuming contaminated food.

Fortunately, food poisoning is not life-threatening, and a person will feel better after a few days without the need for medical attention.

However, if your symptoms are severe or if you don’t start feeling better after a few days, you should always see a doctor.

Proper hygiene should be taken when preparing and handling food to prevent food poisoning.

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