Food Sources of Parasites: Sushi, Pork and Undercooked Meat

Raw fish, undercooked pork and wild game are well-documented routes by which people swallow parasites. This page sets the food points from a 2026 integrative-oncology presentation — sushi, pork, undercooked meat, and a list of foods such as sugar, dairy and alcohol — beside what food-safety agencies and the published research report. It covers which food-borne parasites cause the most harm worldwide, what the United States food agencies state about freezing fish and cooking meat, and what research exists, and does not exist, on sugar, dairy, alcohol and processed food.

Table of Contents

  1. What the Presentation Said
  2. Which Food-Borne Parasites Matter Most
  3. Raw Fish, Sushi and the Anisakis Worm
  4. What the Food and Drug Administration States About Freezing Fish
  5. Fish Tapeworm in Salmon
  6. Pork, the Pork Tapeworm and Cysticercosis
  7. Trichinella: From Pork to Wild Game
  8. What the Agencies State About Cooking Temperatures
  9. Toxoplasma in Meat and Raw Milk
  10. Sugar, Dairy, Alcohol and Processed Food: What Research Exists
  11. How the Claim Compares With the Research
  12. What Is Not Known
  13. Connections
  14. Key Research Papers
  15. Featured Videos

What the Presentation Said

Food came up at three points in the presentation.

The presentation did not cite a study for any of these food points, and it did not name specific fish parasites, Trichinella or Toxoplasma. This page therefore tests the speaker's general claim — that raw fish, pork and undercooked meat are sources of parasites, and that sugar, dairy, alcohol and processed food matter too — against the parasites that food-safety research actually tracks. The cleanse schedule itself is covered on Parasite Cleanse Claims, and heavy metals on Parasites and Heavy Metals.

Which Food-Borne Parasites Matter Most

In 2012 a joint expert meeting of the Food and Agriculture Organization of the United Nations and the World Health Organization scored 24 food-borne parasites on seven criteria, five of them about public health, and published a "top ten" list in 2014. The two agencies listed them in this order, with the foods they named for each:

  1. Taenia solium, the pork tapeworm — in pork
  2. Echinococcus granulosus, the hydatid worm — in fresh produce
  3. Echinococcus multilocularis, a tapeworm — in fresh produce
  4. Toxoplasma gondii, a single-celled parasite — in meat from small ruminants, pork, beef and game meat
  5. Cryptosporidium species — in fresh produce, fruit juice and milk
  6. Entamoeba histolytica — in fresh produce
  7. Trichinella spiralis, the "pork worm" — in pork
  8. Opisthorchiidae, the liver flukes — in freshwater fish
  9. Ascaris roundworms — in fresh produce
  10. Trypanosoma cruzi — in fruit juices

Two points stand out. Pork appears twice in the top seven, which fits the speaker's concern. But fresh produce appears five times: on the agencies' list the hydatid worms, the amoeba and Ascaris come from produce, not meat. The sea-fish worms behind most sushi infections, the Anisakidae, ranked 17th of 24 globally.

Rankings shift by region. A 2016 European workshop using the same scoring method put Echinococcus multilocularis first for Europe, followed by Toxoplasma gondii and Trichinella spiralis; the pork tapeworm, first worldwide, came 10th for Europe, while the Anisakidae made the top ten in every European region (Bouwknegt and colleagues, 2018). The authors concluded that the parasites that matter in Europe differ from those that matter globally.

Raw and lightly cooked freshwater fish dishes, the source of the liver flukes ranked 8th, are covered in detail on Liver Flukes and Bile Duct Cancer, because two of those flukes are classed as causes of cancer.

Raw Fish, Sushi and the Anisakis Worm

Anisakis and its relative Pseudoterranova are roundworms whose larvae live in the flesh of many sea fish and squid. The Centers for Disease Control and Prevention states that when people eat raw or undercooked infected fish or squid they swallow the larvae, which can invade the gastrointestinal tract. The illness is called anisakiasis (or anisakidosis).

What the research reports

Sushi is not one food. The Food and Drug Administration names a range of dishes implicated in human parasite infections: ceviche (fish marinated in lime juice), lomi lomi (salmon marinated in lemon juice), poisson cru, herring roe, sashimi, sushi, lightly brined "green" herring, crabs marinated in wine, cold-smoked fish and undercooked grilled fish. The common thread is that the fish was never heated or frozen enough to kill the larvae. The agency also states that brining and pickling may reduce the parasite hazard but do not eliminate it, and that roundworm larvae have been shown to survive 28 days in a brine of 21% salt by weight.

What the Food and Drug Administration States About Freezing Fish

The figures below are what the agency states in its rules for restaurants and food processors. They describe the conditions the agency considers sufficient to kill parasites; they are reported here as the agency's published standard.

The three freezing options

Section 3-402.11 of the 2022 Food and Drug Administration Food Code, the model code the agency publishes for restaurants and retail food stores, requires that raw, raw-marinated, partially cooked or marinated-partially cooked fish served in ready-to-eat form first be:

The agency's guidance for fish processors (Fish and Fishery Products Hazards and Controls Guidance, chapter 5) gives the same three options, describes them as "sufficient to kill parasites", and adds that they may not be suitable for particularly large fish, for example fish thicker than 6 inches. The same chapter states that tapeworms are more susceptible to freezing than roundworms, and that flukes appear to be more resistant to freezing than roundworms. The Centers for Disease Control and Prevention repeats the three options on its anisakiasis and fish tapeworm pages, and gives 145 °F (about 63 °C) as the internal temperature for adequately cooked fish and seafood.

What the rule does not cover

The Food Code exempts some products from the freezing requirement:

The processor guidance explains the farmed-fish exemption: fish raised only on pellet feed "apparently do not have the same parasite hazard" as wild fish that eat infected prey, but farmed fish fed processing waste, fresh fish or plankton may carry parasites, and fish raised in fresh water can still pick up flukes, which enter through the skin rather than through food.

Freezing kills the larvae, but whether it removes the allergy risk from Anisakis proteins was not covered by the agency documents or by the papers read for this page.

Fish Tapeworm in Salmon

The broad fish tapeworms (Diphyllobothrium species) are caught from fish. The larvae live in the muscle of fish; a person who eats the fish raw or undercooked can grow an adult worm in the intestine. The Centers for Disease Control and Prevention names freshwater fish such as trout, perch and pike, and salmon, as sources, lists vitamin B12 deficiency leading to anaemia among the possible effects, and states that salting, smoking or pickling fish does not kill the parasite.

Published reports

How much vitamin B12 such worms take, and how often that causes anaemia, is covered on Do Parasites Steal Your Nutrients?.

Pork, the Pork Tapeworm and Cysticercosis

The presentation said cysticercosis comes mainly from undercooked pork. The research describes two different illnesses from the same worm, Taenia solium, caught in two different ways:

So eating pork gives the intestinal worm, and the intestinal worm in one person is the source of eggs that give cysticercosis to others — including people who never eat pork. Pigs are infected in turn when they eat human stool containing eggs. A related tapeworm, Taenia saginata, comes from undercooked beef, and Taenia asiatica from pork; the review names only Taenia solium cysts as the cause of neurocysticercosis (Mendlovic and colleagues, 2021). The brain infection, its treatment and the claim that surgery is the only way to remove it are covered on Parasites in the Brain.

Trichinella: From Pork to Wild Game

Trichinella roundworms live as tiny coiled larvae inside the muscle of meat-eating and scavenging animals. A person who eats infected meat that is raw or undercooked releases the larvae, which mature in the gut and produce new larvae that travel to the person's own muscles. The illness, trichinellosis (also called trichinosis), ranges from no symptoms to fatal disease; common signs include fever, swelling around the eyes, muscle pain and a raised count of eosinophils, a type of white blood cell (Wilson and colleagues, 2015).

The shift from farmed pork to wild meat

What the Centers for Disease Control and Prevention states

What the Agencies State About Cooking Temperatures

The figures below are the published standards of United States public-health and food agencies, reported as stated. They are set to control bacteria as well as parasites; the Food and Drug Administration notes that heating raw fish enough to kill bacterial pathogens is also enough to kill parasites.

Centers for Disease Control and Prevention ("Safer Food Choices", 2024)

The United States Department of Agriculture's safe minimum internal temperature chart gives the same 145 °F with a 3-minute rest for whole cuts of pork, and 160 °F for ground pork. The rest time is the time the meat stays at its final temperature after it leaves the heat.

Wild game

Toxoplasma in Meat and Raw Milk

Toxoplasma gondii is a single-celled parasite whose final hosts are cats. People catch it by swallowing tissue cysts in raw or undercooked meat, or the parasite's hardy egg-like stage (oocysts) from cat faeces in soil, water or unwashed produce. Infection during pregnancy is linked to miscarriage, preterm labour and congenital toxoplasmosis in the child (Walana and colleagues, 2026).

The link between Toxoplasma and brain tumours is examined on Toxoplasma and Brain Tumors.

Sugar, Dairy, Alcohol and Processed Food: What Research Exists

Unlike sushi and pork, sugar, dairy, alcohol and processed food are not themselves carriers of the parasites tracked by food-safety agencies. A search of the published research for this page found little that tests the speaker's grouping, and what does exist points in several directions.

Sugar and processed food

No human study was found that links dietary sugar or processed food to catching a parasitic infection or to a heavier worm burden. The experiments that exist are in mice, and they do not line up with the claim:

Neither mouse study shows that sugar is good or harmless for people with parasites; they show that the effect of diet on infection in animals depends on the parasite and the gut site, and that there is no human evidence either way.

Dairy

Pasteurised milk and cheese are not listed as parasite sources by the agencies cited on this page. Unpasteurised (raw) milk is a different matter: the Food and Agriculture Organization of the United Nations and the World Health Organization list milk among the foods that carry Cryptosporidium, the Centers for Disease Control and Prevention lists raw milk and soft cheese made from raw milk under "riskier choice", and drinking unpasteurised milk appears among the risk factors for Toxoplasma infection in pregnancy (Walana and colleagues, 2026). The research therefore separates raw milk from dairy as a whole.

Alcohol

Alcohol does not carry parasites, but research links heavy, long-term drinking to one infection in particular. Strongyloides stercoralis, the threadworm, enters through the skin from contaminated soil rather than through food. A 2013 meta-analysis found an association between alcoholism and Strongyloides infection, with an odds ratio of 6.69 (Schär and colleagues, 2013). A 2025 meta-analysis of seven studies reported a pooled prevalence of 16.9% among people with alcohol use disorder and, in four studies with a comparison group, a 6.08-fold higher risk than in people without it (Machado and colleagues, 2025). The authors suggest environmental, physical and immune factors as explanations. This is an association in observational studies, not proof that alcohol causes the infection.

How the Claim Compares With the Research

Supported by the research

Supported only in part

No research found

Decisions about diet, testing and antiparasitic medicines belong with a clinician.

What Is Not Known

Connections

Key Research Papers

  1. Della-Morte D, Ambrosi C, Chiereghin F, Infante M, Pastore D, Pacifici F, Scaramella M, Gentile L, Mulas F, Quintavalle G. Methods for inactivation of seafood Anisakis larvae and prevention of human anisakiasis: a mini-review. Eur Rev Med Pharmacol Sci. 2023;27(11):5246-5256. PubMed PMID: 37318499
  2. Bouwknegt M, Devleesschauwer B, Graham H, Robertson LJ, van der Giessen JW, Euro-FBP workshop participants. Prioritisation of food-borne parasites in Europe, 2016. Euro Surveill. 2018;23(9):17-00161. PubMed PMID: 29510783
  3. van der Giessen J, Deksne G, Gómez-Morales MA, Troell K, Gomes J, Sotiraki S, Rozycki M, Kucsera I, Djurković-Djaković O, Robertson LJ. Surveillance of foodborne parasitic diseases in Europe in a One Health approach. Parasite Epidemiol Control. 2021;13:e00205. PubMed PMID: 33665388
  4. Sampaio JL, de Andrade VP, Lucas Mda C, Fung L, Gagliardi SM, Santos SR, Mendes CM, Eduardo MB, Dick T. Diphyllobothriasis, Brazil. Emerg Infect Dis. 2005;11(10):1598-1600. PubMed PMID: 16318703
  5. Hutchinson JW, Bass JW, Demers DM, Myers GB. Diphyllobothriasis after eating raw salmon. Hawaii Med J. 1997;56(7):176-177. PubMed PMID: 9264206
  6. Kuchta R, Oros M, Ferguson J, Scholz T. Diphyllobothrium nihonkaiense Tapeworm Larvae in Salmon from North America. Emerg Infect Dis. 2017;23(2):351-353. PubMed PMID: 28098540
  7. Del Brutto OH, Garcia HH. Neurocysticercosis. Handb Clin Neurol. 2013;114:313-325. PubMed PMID: 23829921
  8. Mendlovic F, Fleury A, Flisser A. Zoonotic Taenia infections with focus on cysticercosis due to Taenia solium in swine and humans. Res Vet Sci. 2021;134:69-77. PubMed PMID: 33321377
  9. Murrell KD. The dynamics of Trichinella spiralis epidemiology: Out to pasture? Vet Parasitol. 2016;231:92-96. PubMed PMID: 27061788
  10. Wilson NO, Hall RL, Montgomery SP, Jones JL. Trichinellosis surveillance--United States, 2008-2012. MMWR Surveill Summ. 2015;64(1):1-8. PubMed PMID: 25590865
  11. Cash-Goldwasser S, Ortbahn D, Narayan M, Fitzgerald C, Maldonado K, Currie J, Straily A, Sapp S, Bishop HS, Watson B, Neja M, Qvarnstrom Y, Berman DM, Park SY, Smith K, Holzbauer S. Outbreak of Human Trichinellosis - Arizona, Minnesota, and South Dakota, 2022. MMWR Morb Mortal Wkly Rep. 2024;73(20):456-459. PubMed PMID: 38781100
  12. Diaz JH, Warren RJ, Oster MJ. The Disease Ecology, Epidemiology, Clinical Manifestations, and Management of Trichinellosis Linked to Consumption of Wild Animal Meat. Wilderness Environ Med. 2020;31(2):235-244. PubMed PMID: 32169338
  13. Guo M, Dubey JP, Hill D, Buchanan RL, Gamble HR, Jones JL, Pradhan AK. Prevalence and risk factors for Toxoplasma gondii infection in meat animals and meat products destined for human consumption. J Food Prot. 2015;78(2):457-476. PubMed PMID: 25710166
  14. Walana W, Odai SA, Tamomh AG. Prevalence, risk factors, diagnosis and outcomes of Toxoplasma gondii infection in pregnancy: A review. Parasitol Int. 2026;110:103143. PubMed PMID: 40818495
  15. Israelson H, Vedsted-Jakobsen A, Zhu L, Gagnaire A, von Münchow A, Polakovicova N, Valente AH, Raza A, Andersen-Civil AIS, Olsen JE, Myhill LJ, Geldhof P, Williams AR. Diet composition drives tissue-specific intensity of murine enteric infections. mBio. 2024;15(2):e0260323. PubMed PMID: 38179939
  16. Mattar VNG, Carvalho MO, Silva LCC, Pereira LGACN, Malaquias LKC, Ventura RR, Hermes TA, Novaes RD, Marques MJ, Dos Reis LFC. Alternate-Day Fasting Exacerbates Lung Inflammatory Disease Compared to High-Sucrose Diet in Experimental Schistosomiasis Mansoni. Parasite Immunol. 2026;48(2):e70068. PubMed PMID: 41717881
  17. Schär F, Trostdorf U, Giardina F, Khieu V, Muth S, Marti H, Vounatsou P, Odermatt P. Strongyloides stercoralis: Global Distribution and Risk Factors. PLoS Negl Trop Dis. 2013;7(7):e2288. PubMed PMID: 23875033
  18. Machado GJR, Sampaio MRM, Alves CP, da Silva JLS, de Souza JN, Soares NM. Prevalence and risk of having Strongyloides stercoralis infection in alcoholic patients: a systematic review and meta-analysis. J Helminthol. 2025;99:e128. PubMed PMID: 41347610

PubMed Topic Searches

  1. Anisakiasis, raw fish and freezing
  2. Trichinellosis and wild game meat
  3. Fish tapeworm, salmon and sushi
  4. Risk ranking of food-borne parasites

Other Sources

  1. Food and Drug Administration: Food Code 2022 (sections 3-401.11 and 3-402.11)
  2. Food and Drug Administration: Fish and Fishery Products Hazards and Controls Guidance, Chapter 5 (Parasites)
  3. Centers for Disease Control and Prevention: About Anisakiasis
  4. Centers for Disease Control and Prevention: About Diphyllobothrium
  5. Centers for Disease Control and Prevention: Preventing Trichinellosis
  6. Centers for Disease Control and Prevention: Safer Food Choices (2024)
  7. United States Department of Agriculture: Safe Minimum Internal Temperature Chart
  8. Food and Agriculture Organization of the United Nations: "Top Ten" list of food-borne parasites released (2014)