Food With Parasites


Food With Parasites seeks to bring awareness to what some people may find gross and disgusting but others may find fascinating. Understanding the food you eat, and knowing what goes on behind the scenes can be fascinating.

Food With Parasites

Here’s a breakdown of some of the most common food sources of parasites:

  • undercooked pork
  • other undercooked or raw meats, such as beef
  • raw fruits and vegetables
  • raw or undercooked freshwater or marine fish
  • raw or undercooked crustaceans or mollusks
  • raw aquatic plants such as watercress
  • unpasteurized cider and milk

What are some of the most common parasites?

These foods can lead to dozens of different infections and illnesses when not handled and prepared correctly. Some of the parasites that affect humans via food or water are:

  • Giardia: This is the most commonly identified intestinal parasite in Canada. It can come from drinking untreated water.
  • Cyclospora: This parasite is passed to humans through contaminated food or water. The eggs are shed in the stool of infected people.
  • Pinworms: These can be passed on to customers by Food Handlers who haven’t adequately washed their hands after using the washroom. Roundworms, a type of pinworm, are also commonly transferred to humans by the fecal-to-oral route.
  • Tapeworms: These usually affect humans who ingest undercooked beef, pork or fish containing the larvae that later grow into full tapeworms inside a person’s intestines.
  • Taenia: This is a type of tapeworm, often referred to as “pork tapeworm” since it generally comes from raw or undercooked pork products.
  • Trichinella: Like tapeworms, these are ingested in larval form when people eat raw or undercooked meats.
  • Toxoplasma: This parasite can come from both undercooked contaminated meats as well as raw produce that has been infected and not adequately cleaned before consumption.
  • Anisakis: This worm can be found in sushi or sashimi that was not prepared properly. Undercooked marine fish (e.g. cod, flounder, haddock, Pacific salmon) and squid are the usual culprits.
  • Phocanema: Like anisakis, these parasites are also transmitted to humans through raw or undercooked marine fish.
  • Clonorchis and Paragonimus: Sometimes called flukes, these parasites originate from freshwater fish and crustaceans that have not been cleaned or cooked adequately.
  • Cryptosporidium: This parasite infects humans who consume unpasteurized cider and milk, and raw or undercooked shellfish.
What are the symptoms of food-borne illness caused by a parasite?

If you have a parasitic infection, you may exhibit no symptoms, or mild ones. Your symptoms will depend on the type of parasite that’s making you sick. Some of these symptoms include:

  • nausea
  • lack of appetite and weight loss
  • diarrhea
  • abdominal pain and bloating
  • weight loss
  • fatigue and general weakness

Sometimes, parasites can even cause death to the people they’ve infected.

Parasites can be extremely difficult to get rid of once they’re in your body, so prevention is key.

How can I prevent food-borne parasitic infections?

Most instances of food-borne illness are caused by poor hygiene, ineffective cleaning and sanitizing and inadequate time and temperature control.

As many parasites are transferred in unsanitary conditions along the supply chain, if you work in a food business, you need to ensure you only accept foods from reputable suppliers — especially high-risk or potentially hazardous foods such as raw fish and shellfish, fresh pork or beef. Check these foods thoroughly before accepting them. With fish, touch it and smell it. It should not have a strong fishy odour, and it should be firm and springy to the touch.

Most parasites can be killed with thorough cooking processes — as a general rule, food must be cooked to a temperature of 74°C / 165°F or above (82°C / 180°F or higher in Manitoba). Remember to follow the safe food cooking temperatures of potentially hazardous foods! When it comes to sushi or sashimi, strict time and temperature controls must be maintained to ensure safety.

And the most effective way to prevent parasites? Wash, wash, wash your hands! The importance of proper hand washing cannot be overstated. Ensure all Food Handlers wash their hands, especially after using the washroom, for at least 20 seconds in hot water using liquid soap.

Preventing every food-borne illness — not just parasitic infections — and keeping customers safe should be the top priority for anyone who works in the food service industry.

The top ten parasites that could be lurking in your food

Disclosure statement

Helena receives funding from Bill and Melinda Gates Foundation for her research on immunity to intestinal nematode infections


The Conversation is funded by the National Research Foundation, eight universities, including the Cape Peninsula University of Technology, Rhodes University, Stellenbosch University and the Universities of Cape Town, Johannesburg, Kwa-Zulu Natal, Pretoria, and South Africa. It is hosted by the Universities of the Witwatersrand and Western Cape, the African Population and Health Research Centre and the Nigerian Academy of Science. The Bill & Melinda Gates Foundation is a Strategic Partner. 

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Hey! You got a friend in Taenia solium. Roberto J. Galindo, CC BY-NC-SA

Most people are fascinated, and probably equally repulsed, by parasites. And it may be something you think you only need to worry about if you go on holiday somewhere exotic. However, increasing globalisation and transportation of food products across the globe means we are all increasingly at risk of catching something unwanted from our favourite foods.

Many infections can be thwarted with proper hygiene – washing fruit and vegetables, including “ready-washed” lettuce, cooking meat properly and avoiding contamination from domestic or wild animals. A joint UN/WHO report said better farming and global food trade standards could also prevent parasites entering the food chain. Experts have ranked the 24 most damaging food-borne parasites according to number of cases, global distribution and health impact. Here are the top ten:

1. Taenia solium

T.solium, also known as pork tapeworms, can measure up to 10m when mature and are among the biggest of these ribbon-like worms to infect humans. They do this through larval cysts in undercooked pork that hatch in the stomach and quickly grow into adult worms which inhabit the intestine, feeding on the nutrients you eat.

Disease is generally restricted to malnutrition as the worm competes with you for food – unless you ingest eggs rather than a cyst. These migrate around the body before forming larval cysts – a condition called cysticercosis – just like they do in the pigs. This can cause severe problems, particularly in the central nervous system (neurocysticercosis) where they can cause epileptic seizures. This is believed to be a main cause of epilepsy in many poorer parts of the world.

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2. Echinococcus granulosus

Growing up with not a care in the world. CDC/L.L.A. Moore, Jr

Another tapeworm, but only 3-7mm long, which causes a nasty disease called cystic echinococcosis (CE). The worm has a life cycle that normally cycles between carnivores (usually dogs), and sheep or other livestock. Humans become infected through accidental ingestion of eggs from dog faeces, either through contaminated food products or from direct contact, or contaminated soil. The worm’s eggs are tough – they can remain infective for months, even in freezing temperatures.

More than a million cases of CE occur every year worldwide, mainly in areas where livestock, including camels, come in to close contact with dogs. After ingesting eggs, the parasite migrates, primarily to the liver. Slow-growing cysts form and symptoms may not be obvious until several years later. Cysts can contain several litres of fluid and are full of infectious larval stages called protoscoleces. Spontaneous rupture of the cysts can be very dangerous and lead to fatal shock.

3. Echinococcus multilocularis

No, I encyst. CDC/I. Kagan

Geographical distribution of this tapeworm is patchy but it’s found in both North America and Europe where prevalence is slowly increasing. Its life cycle normally involves foxes and small rodents but can happen in domestic dogs and even cats. In humans it causes a disease called alveolar echinococcosis, which forms cysts in internal organs. The cysts can reproduce and spread like tumours and be fatal if untreated. This infection is considered a risk factor for hunters who handle infected fox carcasses and people foraging for berries and mushrooms contaminated by fox faeces.

4. Toxoplasma gondii

Secreted away.  Ke Hu/John Murray/PLOS

T.gondii is a single-cell parasitic animal (protozoa) that can infect practically all warm-blooded mammals, but its life cycle normally takes place between cats and rodents. T.gondii is present in most countries and is one of the most widespread protozoan parasites affecting humans. Infection rate in humans varies between 10-80% of the population in different parts of the world and the parasite usually stays dormant in the tissues for the lifetime of the host – most infected people have no symptoms and never know they’re infected.

The most serious problems arise in pregnant women because the parasite can cross the placenta and cause foetal abnormalities or even miscarriage, which is why its advisable for them to avoid cleaning cat litter. Immunosuppressed individuals, such as HIV/AIDS and organ transplant patients, are also at risk because the parasite can start multiplying uncontrollably.

5. Cryptosporidium spp.

Not the eggs you want in the morning. Alae-eddine GATI, CC BY-SA

These protozoan parasites are mainly transmitted via contaminated water or food washed in contaminated water. Unpasteurised cider and milk, and contaminated shellfish have been implicated in several outbreaks. The parasite is present worldwide, including the UK, and infection is often caused by foecal contamination of water supplies by infected livestock. In healthy individuals the disease causes severe watery diarrhoea, which often rights itself. Thorough washing of fresh produce – including “ready washed” lettuces – is recommended.

6. Entamoeba histolytica

Cyst-ematic infection. CDC/George Healy

Another protozoan parasite that infects the digestive tract causes amoebic dysentery. The disease is characterised by bloody diarrhoea and abdominal pain that can become life threatening. More severe problems can occur if the parasite starts spreading from the intestine out into the body, causing abscesses in the liver and other organs.

7. Trichinella spiralis

Spiraling problem. CDC

Trichinella spiralis, is an intracellular “pork roundworm” responsible for trichinellosis, a muscle infection caught from eating raw or undercooked pork, or pork products such as smoked sausages. Other sources include game such as wild boar, and even walrus. Infected meat is contaminated with cysts, invisible to the eye, that contain a small larvae. When the meat is digested, these grow into adult worms that mate and produce thousands of new larvae, which travel out into the muscle tissues where they encyst, awaiting the current host to be eaten.

8. Opisthorchiidae

Clonorchis: from the Chinese branch of the family. Circa24, CC BY-SA

This is a family of flatworms, or flukes, mainly present in south-east Asia (though some species are also present in Europe and Russia). The infection is contracted through eating raw or undercooked freshwater fish that have themselves been snails infected with larvae. These develop into another type of larvae in fish, and when they are eaten by a mammal (such as a human) they turn into adult worms that make themselves at home in the bile duct and gall bladder. It then produces eggs that are excreted in faeces, which hatch to infect new snails when they reach a fresh water source.

Infected dogs and cats roaming freely in villages are often significant reservoirs of infection. Chronic long-term Opisthorchis infections are significantly associated with cancer of the liver and bile ducts. Freezing or cooking fish prevents infection – pickling, drying, salting or smoking fish won’t.

9. Ascaris spp.

Do not swallow. Alan R Walker, CC BY-SA

These are the largest of the human intestinal roundworms (up to 35cm) and with 25% of the world infected, is the most common parasite in humans. After ingestion, the eggs hatch into larvae in the intestine before undergoing a remarkable migration: they travel out of the intestine via the blood to the lungs, then migrate up the airways to the throat, where they get swallowed down into the stomach and back to the intestine again, where they finally develop into adult worms.

Each female worm produces hundreds of thousands of eggs per day which are excreted in the faeces, contaminating the environment and further spreading the disease. A second species, Ascaris suum, was until recently believed to only infect pigs but is also able to infect humans. The level and symptoms of disease depends on the number of worms the individual is infected with, and intestinal blockage can happen because of the size of the worms.

10. Trypanosoma cruzi

Some flowers would do. CDC/WHO

T.cruzi is a protozoan parasite which causes a disease called Chagas disease. The disease is characterised by slow progression where the parasite infects various cells and organs in the body, including the heart, over many years, often with no or only mild symptoms present. Eventually the disease manifests itself through serious, and sometime fatal, cardiac or intestinal problems.

The infection is normally transmitted though contact with the faeces of triatomine beetles (“kissing bugs”), which seek nightly human contact to feed on human blood. When it feeds, the beetle defecates on the host’s skin. Bug faeces are often then scratched into the bite wound. T.cruzi is on the top ten list because it was recently discovered that humans can be infected by simply ingesting foods contaminated with bug faeces – several outbreaks in recent years were caused by contaminated fruit and sugar cane juices – causing concern that it could become a global pathogen.

Top 6 Most Powerful Anti-Parasitic Foods

Here is a list of 6 anti-parasitic foods that can help you kill parasites naturally.

1. Pineapple

The core of the pineapple is abundant in an enzyme known as bromelain, which can boost digestion and kill parasites. Pineapple juice can decrease the production of proinflammatory cytokines that can result in colon inflammation.

Bromelain is also great for breaking down protein foods, which makes it great for fighting intestinal parasites as it can kill worms. Regular consumption of pineapple can make your immune system healthier and help it to fight and eliminate parasites.

2. Pumpkin Seeds

Pumpkin seeds are commonly used to treat parasites as they contain tetracyclic triterpenes which can help remove parasites from the body.

Apart from that, pumpkin seeds contain cucurbitins that can paralyze worms and make it difficult for them to hide within the intestinal walls. This facilitates their removal from the body during a bowel movement.

3. Cucumber Seeds

Cucumber seeds are great for removing tapeworms that reside in the digestive tract. That’s why it is a good idea to consume cucumber seeds even if you do not have a parasite, as a precautionary measure. The enzymes found in cucumber can kill tapeworms.

Though if you are experiencing tapeworms, then it is best to go directly to a medial professional like the best gastroenterologist in Karachi

4. Garlic

The medicinal properties of garlic have been known since ancient times and it is used by people all over the world to boost appetite, strengthen the immune system, kill parasites, and treat travel sickness. Garlic is rich in sulfur compounds that can destroy pathogenic organisms and decrease the formation of blood clots.

Garlic can boost the production of stomach acids, which is crucial as chronically low stomach acid has been linked to bacteria and yeast overgrowth in the gut.

5. Ginger

Just like garlic, ginger can also increase the production of stomach acid, which can kill parasites and prevent infections. Apart from that, ginger can increase blood circulation and is good for all types of digestive issues.

6. Apple Cider Vinegar

Since apple cider vinegar contains B-vitamins, it is very nourishing for the body. It can also restore natural pH balance, improve digestion, and kill parasites.


If you think that you have parasites, visit a gastroenterologist. You can find and book an appointment with the best  Gastroenterologists in Islamabad, Karachi, and Lahore through You can also call our helpline at 042-3890-0939 for assistance to find the RIGHT Doctor for your health concerns.

What Foods Are a Risk of Parasite Infection?

Parasitic infections and food.

Most patients are very surprised to learn that the symptoms they are experiencing are caused by the presence of parasites in their organism. Yes, parasites can very easily find their way inside our bodies and once they are there, the symptoms they can cause are numerous. Parasitic infection can be quite confusing because its symptoms can range from mild physical pain in the stomach to psychological disorders as severe as depression.

Contrary to the popular belief, parasites are not an issue only in the undeveloped countries where most people will get infected from the unclean tap water. The greatest risk of parasitic infection actually is the food we eat and parasites can easily be hidden in your daily meal. Although almost every person has been a host to parasites at some point in life, in some cases they can cause serious health issues. Therefore, regular check-ups and occasional parasite cleanse is highly recommended. However, in order to eliminate parasites and cure your body of the damage done, one should use a natural herbal supplement for parasite cleanse and make several dietary changes.

So let’s take a look at what foods are most likely to be hosting parasites and how to choose what to include or exclude from your diet in order to eliminate parasites and avoid getting infected.

What Are Parasites?

Parasites are very small, in some cases microscopic organisms that derive protection and nourishment from another living organism. Parasites live inside or on the organism known as the host. Parasites live and reproduce inside the organs or within the tissues of the host (human or animal) and can be exerted with feces. In some cases, they are not exerted and can stay and thrive inside the organism for quite a while causing health issues. That mostly depends on the type of the parasite as some use a permanent host, and others use different animal or human hosts to aid their development phases.

The types of parasites are numerous and they range in size and form. They can be represented as single-celled organisms (ameba) to worms that are visible to the naked eye. In some patients, worms that have been thriving inside the organism can grow amazingly long. These worms are known as a tapeworm or Taenia saginata. Other common parasites in humans are giardia lamblia, hookworm, scabies mite, roundworm, and flatworm – blood fluke. All these mentioned above can be present in the food we eat and cause what is known as foodborne illness.

Types of Foods That Are Most Likely to Host Parasites

Parasites are mostly related to eating raw food. The high heat, when cooking, easily eliminates parasites and there is a very low risk of parasitic infection. On the other hand, raw vegetables, fruits and meat are at high risk of parasite transmission.

Fresh Fruits and Vegetables

Eating raw or lightly cooked vegetables has resulted in an increased number of people infected with parasites. Raw vegetables and fruits are hosts to some types of parasites. The chances are increased when these foods are imported. Global trade and the time needed for the food to travel from point A to point B is in favor of parasites developing and reproducing. Proper washing of the raw foods before eating lowers the risk of parasites getting inside the body. However, with some vegetables such as lettuce, cabbage, iceberg lettuce that are hard to be thoroughly washed, parasites can easily stay on the leaves and be ingested.

When it comes to protecting yourself from parasitic infection it is highly recommended for the food to be chemically treated in order to avoid ingesting parasites. Moreover, wastewater reuse is common in agriculture these days, which can contaminate the fields during harvesting, growing, transporting, and storage. Organic farming also poses a great risk of an increased parasitic contamination.

Raw Meat and Fish

Raw meat is the perfect environment for a parasite to thrive. They can easily be hidden in raw fish and meat and if these are not cooked parasites will be ingested. As mentioned above, the meat we eat today is mostly imported from other countries. The meat has traveled for quite a while and the unfamiliar conditions it was handled in (most commonly not the recommended low temperatures and away from light) increase the risk of high parasitic contamination. That benign said it is very risky and almost unlikely to not get a parasite when eating:

  • undercooked fish: the most common source of parasites is Sushi and raw salmon
  • Undercooked crabs, seafood, and even raw aquatic plants
  • undercooked meat of any type

Any type of food, including cooked and prepared meals in a public restaurant/place can also be infected with parasites. Moreover, some foods can be contaminated by food service workers who work in unsanitary facilities and/or practice poor hygiene.

Other Sources of Parasites

Apart from food, one can easily get infected with some types of parasites by drinking unsafe water. Additionally, people that are living with pets are at a higher risk of infection. Parasites are much more common in dogs and sharing your bed with them or being very close to a dog can allow parasites to transfer and pick you as their next host. Swimming in a pool that is shared with more people or regular swims in a freshwater lake can also pose a risk of getting infected with some sort of parasite.

All this benign mentioned, it seems impossible to avoid all risk factors and not get infected with parasites. It’s important, however, to be aware of any symptoms that might be a sign of parasitic infection and acting on them. Performing a thorough body cleanse is recommended to all people for enhancing the intestinal and digestive health, so a detox twice a year should kill any parasites that might be affecting you and help you prevent yourself from various illnesses and fatigue.

About the Author

Sarah Peterson is a certified holistic nutritionist. She has been studying the power of herbs and holistic approach to health and illness for over 10 years now. After suffering a series of autoimmune diseases, she decides to take control of her life. Right after a thyroid gland failure, Sarah decides to make some serious life changes and started studying and incorporating holistic approaches and has successfully healed her thyroid without the use of medication or surgery. After studying alternative medicine, Sarah has also enrolled in medical school and still learning and improving, although well in her thirties now. She occasionally writes on important health subjects in order to spread her knowledge and help people heal through a holistic approach. She still propagates the power of natural healing for wellness but diagnoses and talks from a medical professional’s point of view.

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