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Consuming Raw Fish Safe or Not

Updated on February 4, 2010
Frank Carter, Lonely Planet Image
Frank Carter, Lonely Planet Image

I'm not a raw fish eater and this hub is not against raw fish eater and sushi eater. Sushi can contain raw fish but also can contain cooked or otherwise prepared seafood and vegetables.
Human being has been eating raw fish millions of years and fish can be much better consumed raw than meat. I can't imagine consume raw meat either, I can't consume anything raw beside fruits and veggie.
Raw fish is a traditional delicacy in many cultures. Sushi, sashimi, ceviche, gravlax, salmon tartar, and lawar in my country (especially in East Nusa Tenggara, Indonesia). Unfortunately this raw fish could contain of parasites if it is not handled well.

Raw Fish Parasites

There are two types of worms present in local fish that can cause illness in humans.
1. Anisakis, a little roundcoiled worm.
2. Diphyllobothrium, the long and hungry parasite.

Anisakis is found in salt water fish such as salmon, pollock, cod, and halibut. If somebody ingest a live worm, the person will feel abdominal pain and maybe vomitting. If the worm is not expelled, it can cling to a human intestinal wall and creating abdominal disturbances.
In some rare cases, the worm penetrates the intestinal wall and causes a life threatening infection called peritonitis.

While Diphyllobothrium causes a subtler problem. We may carry these worms for years without knowing it. The parasites can grow to a length of ten meters, and may causing weakness and anemia. The parasites will rob the nutrition. These kind of worms infect many species of fresh water fish like trout and salmon.

Believe it or not parasitic infections from freshwater fish/shellfish are very problematic in some parts of the world (e.g. Southeast Asia.)

There are over 50 helminthic infections from fish/shellfish (i.e. parasites that parasitizes the human gut) that can infect humans.

According to Paul Carnes, M.D from Fisherman's Journal, those who love sashimi there are a couple of precautions you can take.Luckily most parasitic infections from ocean fish are rare. Pelagic fishes, such as tuna probably have the least amount of parasitic load. This is mainly due to their wide roaming migrations. This is because tuna, who are near the top of

the food chain, may consume prey that have parasites, but are not in an area long enough to ingest many prey that might have a high parasitic load. What this does is decrease the likelihood of becoming infected. There are however case reports of humans becoming infected with roundworms after ingesting raw Yellowfin tuna.  Homeguard fish are more likely to have parasites simply because they don't move around much. Thus they continue to consume prey that may have parasites. Juvenile or smaller fish also have less time to have become infected with parasites. Also fishes that grow quickly also have less time to pick up parasites.

True Story of a man with maggots in his head

This is a real story of an old man named Shota Fujiwara, 80 years old. He is from Gifu Prefecture, Japan. He loved to consume raw fish like shusi and sashimi for years. He had suffered unusually painful headache for 3 years and has lost his psicometric ability since then. After undergoing CT-scans & X-rays, the doctors that were treating him had found worms' nest under his head's skin,luckyly as the worms did not penetrate through his skull and into his brain.

The worms on the head of Shota Fujiwara are actually the parasites that usually found on the body of raw fish. This parasite worms can only be killed by the process of high temperatured heating. Or by freezing it in -10 degree Celsius to -20 degree Celsius.

Please be cautious of the pictures.

Shota Fujiwara's head after had been surgical cut
Shota Fujiwara's head after had been surgical cut
the maggot inside Shota Fujiwara's head
the maggot inside Shota Fujiwara's head

How to handle raw fish

I think most of professional sushi chefs will have trained to serve the raw fish in a healthy and higienic way. There is nothing to be worry of. If you love to prepare the raw fish yourself, you may consider these :

1. Clean your fish right away. The parasites live in the fish's digestive tract, so if you remove the guts immediately, you will minimize the risk.

2. Cook or freeze your fish before you eat it, fish cooked to a temperature of 140 degree will not have live parasites in it. Fish that is frozen to -35 degree C (-31 degree F) for fifteen hours will be free of live worms. Most household freezers do not get this cold, but you can freeze your fish for seven days at -20 degree C (-4 degree F). Stay away from raw salmon unless it has been frozen, smoked or farm raised. Don't experiment with consuming new types of raw fish, especially freshwater fish-you may
regret it later.

3. Before serving raw fish, you have to inspect it closely. Cut it into thin pieces and illuminate the flesh over a bright light. That's why a really sharp and high quality knife is needed in serving raw fish. Anisakis worms are tightly coiled, clear, and about half an inch long. Tapeworm larvae resemble a grain of white rice.

How to determine if the fish is fresh or not,

To judge fish on freshness, it has to be a whole fish ; the slime-layer must be intact, and the gills should be moist and bright red. (except for mackerel, whose gills are brown) The scales must be both intact and shiny, and firmly attached to the body. The cut-wound edges must have a fresh scent. The flesh has to be firm. Poking your finger in the flesh, it has to bounce back.

Fresh fish has convex eyes, which shouldn't be bloody but bright white, with shiny black pupils. There should not be any signs of browning (due to oxidation).

So the conclusion is we have to handle or make sure that the raw fish we consume is handled properly and in a hygienic ways.

How to Make Sushi


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    • profile image

      Ronnie Hughes 17 months ago

      This is madness! Why would anybody knowingly consume anything with worms in it?!?! Do we really know all the negative implications of consuming worms? Maybe there are long range consequences that have not been discovered. Maybe the consumption of worms can lead to cancer or heart disease or any number of diseases. Who knows? They can't be good for you! I don't understand how anybody can consume anything after actually seeing the worms!! That is crazy! Insane! Are they so addicted to a particular food that will consume it after seeing the worms?? Are you sure that only people beholding to the fish industry posted these insane comments? I fish a lot, but for small bottom dwelling species like porgies and black sea bass. I fillet them and I intensively scrutinize their flesh. I have never detected any worms or parasites of any kind. If I did I would stop eating them!! No thoroughly cooking them, or removing the worms, or freezing them, no, no! I mostly fish in Montauk and I have noticed that there is never any mention of worms in cod fish flesh! I wonder why? I guess making money is more important to them (boat owners and employees) than informing the fares of the dangers of consuming cod fish. This is criminal

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      shocked 5 years ago

      This is both fascinating and disturbing and gross. I will never eat raw sunshine again!

    • profile image

      thankful 6 years ago

      Thank you Peepo for your blog. It is true, brain maggots are not caused by eating sushi and it is silly to put such fear in people. Yes, you can get food poisoning from any food not prepared properly. And, thank you Harry Santos, Japanese culture does have great health statistics because of all the clean raw food they eat! I will continue to eat it regardless of the gross pictures.

    • profile image

      Peepo 6 years ago

      The pictures are real, but the infestation (cerebral myaisis) was caused by a rare form of cancer (angiosarcoma) that went untreated, mixed with poor living conditions. You can read about it in the journal Neurosurgery if you have university access. It is not caused by eating sushi. There's only been about 8 documented cases of brain maggots, none related to sushi.

    • profile image

      christian 6 years ago

      is there someone knows how to prevent this kind's of parasites and how? or a drugs? and kind of signs

    • profile image

      STUPID PEOPLE 6 years ago

      you all are stupid. IDIOTS !!! it's a hoax... it's not tru. raw fish does not make you develop brain maggots . . . just some stomac ache if not fresh. you are soooo ignorant...

    • febriedethan profile image

      febriedethan 7 years ago from Indonesia

      Hi Harry, thank you for sharing this wise words with us, have a great day!

    • Harry Santos profile image

      Harry Santos 7 years ago from Metro Manila, Philippines

      i think there is a risk with eating anything. With absolutely anything at all you can get diseases. You can even get these things from a well-cooked meat.

      You can even be eating something very healthy then choke on it and die. There is a risk in everything. It does not mean that we should stop eating or stop trying out new things. I've been eating raw fish since I was a kid and I'm absolutely well.

      Even Japanese people seem to be very healthy. They even have healthier diets than those who consume well-cooked fast food that is just full of transfats.

      With any kind of food, there is a risk.

    • febriedethan profile image

      febriedethan 7 years ago from Indonesia

      Dear worm not only in sushi, thank you for the great information! And I agree with you for always eat well cooked meat, fish, and vegetables, and rinse them well.

    • profile image

      worms are not only in sushi 7 years ago

      But not only raw fish can transmit worms, undercooked fish carries a risk too, and this is both for freshwater and saltwater fish.

      Although if the fish is frozen at low enough temperatures (which can't be reached by home freezers) for enough time, it will be completely safe to eat even raw, unless you have an allergy to the toxins secreted by worms, which can't be taken out of the flesh even if the worms are removed by the chef.

      And also, there's not only worms in fish, but also in meat. Pork and beef have a lot of parasites for example.

      The pork tapeworm is much more dangerous than any worm you might contract from raw fish, because there are often brain complications, with larvae encased in cysts moving to the brain, which causes seizures (and death). If the cysts move into the eyes, they can cause retinal detachment, if the retina is not reattached, it will lead to blindness.

      Worm eggs are also very common on many vegetables and fruits.

      The only solution is to only eat well cooked meat, fish and vegetables, and to rinse fruits and vegetables well, and to peel their skin. Leafy vegetables like salads which are impossible to completely wash, should be avoided.

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      jon 7 years ago

      i am a sushi chef and a bit disappointed with the picture you've shown its a bit xtreme,as far as sushi is prepared in a clean environment area there shoul not be a problem, and plus sushi chef like myself are trained in a such a high standard procedure.showing this type of picture is un-necessary,anyway people should have a knowledge of what they eat before actually having far as health and safety standard today is much better now than it used to be so this picture is nothing to do with sushi at all just trying to put off people from having sushi, i agree with the safety and everthing but this is ridiculous,

    • lender3212000 profile image

      lender3212000 8 years ago from Beverly Hills, CA

      Makes me think twice about the sushi I love so much!

    • febriedethan profile image

      febriedethan 8 years ago from Indonesia

      Soop, thank you for the explanation now many of raw fish eater will be very relief and I feel relief too, who knows someday I will try to consume raw fish. But still, it's important to consume fresh and frozen raw fish to make sure that all the parasites are over. Thank's again!

    • profile image

      soop 8 years ago

      Those photos have nothing to do with someone who ate sushi. The real story is here.

    • febriedethan profile image

      febriedethan 8 years ago from Indonesia

      Mickey Dee, yes of course :) Thank's for visiting!

    • Micky Dee profile image

      Micky Dee 8 years ago

      Very -uh- informing! I do love sushi. I'll rely on a great chef! Thanks

    • febriedethan profile image

      febriedethan 8 years ago from Indonesia

      Charlesroring, I think if the fish is still frozen and the chef is professional, will be ok to have one :) the picture is a rare case and I think Mr. Fujiwara is not consuming raw fish in hygienic condition. Thank you for commenting!

    • charlesroring profile image

      charlesroring 8 years ago

      After looking at the pictures, I have decided not to eat raw fish.

    • febriedethan profile image

      febriedethan 8 years ago from Indonesia

      travel_man, I'm sorry to hear that, I know those pictures are horrible and I'm not intend to make somebody to vomit here :) even me is still have a goosebumps watching those, thank's for commenting!

    • travel_man1971 profile image

      Ireno Alcala 8 years ago from Bicol, Philippines

      When my niece saw the photos, she wanted to vomit. This is a reality. Fish when eaten raw can cause adverse effects to us, especially when it has parasites that can be killed only when you cook it.

    • febriedethan profile image

      febriedethan 8 years ago from Indonesia

      genrp, I agree, anything has to be in a certain amount and we have to consume it in hygienic way, thank's

    • genrp profile image

      Genie Rose Palabay-De Guzman 8 years ago from North Hollywood, CA, USA

      OMG! I love eating raw fish..sushi,'s the best..but I don't eat too often..anything taken in excess is dangerous..

    • febriedethan profile image

      febriedethan 8 years ago from Indonesia

      hello,hello, I never eat raw fish too, but i think for raw fish consumer, it will be ok, since the fish is in frozen condition!

      Stevenswoman, hi..write on hub is fun and I think it's ok to consume raw fish, just make sure that the fish is really fresh, keep frozen, and well prepared. Thank you for visiting! Have a great day!

    • febriedethan profile image

      febriedethan 8 years ago from Indonesia

      Tim-tim,yes unfortunately the pictures were so horrible, but I think consuming sushi (specially the raw fish part)is fine since it's prepared in an exact way, thank you for commenting!

      Mama Sez, yes..OMG haha, thank's

    • stevenswoman profile image

      stevenswoman 8 years ago from Ohio

      Hello, Thanks for commenting on my encourages me. I feel so silly when I try to write a hub. I will keep it up...I love to write. O I love sushi!!! I admit that my favorite is the rainbow roll...but I am not sure if I will eat that again...I do know about parasites...I guess I just took my chances. My family is huge into herbals and know some things about parasites. Thank you.

    • Hello, hello, profile image

      Hello, hello, 8 years ago from London, UK

      Unusual but interesting. I never eaten raw fish and I don't think I would ever, even before I read your hub.

    • Mama Sez profile image

      Mama Sez 8 years ago from Canada


    • tim-tim profile image

      Priscilla Chan 8 years ago from Normal, Illinois

      I love my Sushi but I don't like the pictures which you have here! It is disgusting:( I don't know if I can eat again.