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Little Worms in Cod?

So the cod from my fish share this week had some little worms in it. I thought I had pulled them all out but after lovingly making cod cakes yesterday I found two more little worms on the plate next to said cod cakes and just couldn't bring myself to eat any. Am I crazy / unneccessarily squeamish???

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  1. Welp, worms in fish are common...swordfish being a typical worm farm. If you can see the worms they aren't typically parasitic but very off-putting. The worms die at high heat, as do parasitic worms but I urge you to do a little research to educate yourself as there a re quite a few parasites that infest/infect food items.
    The choice whether you want to eat them is yours from a squeamish standpoint but if you eat fish with ANY regularity, you have doubtlessly eaten worms. I'm sure most people wouldn't voluntarily ingest them but we tend to ignore the things we can't obviously see.

    My husband (a microbiologist) and I (a chef) have discussions at length about these types of things and, believe me, we have very different points of view on food in-general. He's a well-done meat kinda guy & I am a med-rare. Its all in the comfort level.
    But of course, I'm always right.

    1. Worms in cod, eh?

      No more cod for da' Khan.

      11 Replies
      1. re: Perilagu Khan

        T'were ever thus. I worked in a fish and chips shop when I was at UCB a good while ago and the owner was forever removing them from the planks of frozeen Icelandic cod we used. Little round things. Yuk. Still ate/eat the fish, though!

        1. re: buttertart

          You're a braver "man" than me, Gunga Din.

          If it has a rep for harboring worms, then I'm quitsville. And if that means I have to forego all fish, so be it.

          Incidentally, are worms more of a problem with ocean fish, or are they present in freshwater fish as well? I'd really hate to give up trout, catfish and salmon.

            1. re: buttertart

              Well, we need to clear this up. Are there any worm-resistent fish?

              1. re: Perilagu Khan

                If you weren't squeamish before, then definitely do NOT read this.


                1. re: ipsedixit

                  Beginning to sound like I'm going to give up fish. And that blows rocks.

                  1. re: ipsedixit

                    The photos with that article have nothing to do with sushi. completely unrelated to eating raw fish.


              2. re: Perilagu Khan

                Fyi, Khan, I have found worms in salmon.

                1. re: Perilagu Khan

                  Some freshwater fish are wormy, too.

                  1. re: elegraph

                    elegraph - many in fact. a few years back in the Ozarks on a float trip (city boy, pfff) caught some crawdads and had the bright idea of 'River Sashimi!' many many months and medical tests later at one of the finest hospitals in the region (Barnes) they narrowed it down to an uncooked parasite from said mudbug.

                2. re: buttertart

                  b'tart - the fish n chips place on Shattuck near Hearst? by the fusty old lady bar? (both gone I think)

                  they were pretty good IIRC, first time I was ever given my choice of fish in the states.

              3. Last year I returned some cod to whole foods that had worms in it. I knew the guy was right when we said that they are normally in there and they try to remove all and that it wouldn't hurt me, but I couldn't bring myself to eat it. So I don't think you are unnecessarily squeamish.

                And in my mind, it's a big difference to say, "hey you've eaten them countless times and didn't realize it" to "here it is next to your freshly made codfish cakes, just ignore it and keep eating".

                I'm curious to hear what others think.

                1. I've found worms in locally caught Halibut. Bought some fresh, squeezed a little lemon juice on it and bang, the buggers were crawling out of the woodwork.
                  Monger told me it's very common in fish, but ..... yuck.

                  1 Reply
                  1. re: janetms383

                    did you eat it after removing the worms?

                  2. I've read the deep sea fish don't typically have parasites and worms.

                    Otherwise sushi fish would be way too dangerous to eat.

                    2 Replies
                    1. re: tomishungry

                      What fish are you defining as deep sea? Just curious. Cod (not that there's a lot of it out there anymore, sadly) is pretty much a deep sea fish, isn't it?

                      1. re: tomishungry

                        Sushi-grade fish sold in the U.S. must be frozen to kill the parasites. Even in the fancy sushi places, the fish was flash frozen on a boat, to preserve freshness, and to kill any worms.

                        I've seen academic science papers where scientists troll through sushi restaurants, and count how many worms they can find in the fish. In almost every case they find worms in the sushi, but they're dead worms.

                        All this talk of sushi has me hungry. Might have to go out for sushi tonight!

                      2. OMG. I made swordfish for dinner and sould hardly swallow it after reading this thread! UGH.

                        1 Reply
                        1. re: emilief

                          Kind of took all the pleasure out of it, didn't it? :(

                          1. Is it true that farmed fish is far less likely to have worms than wild caught?

                            Are ocean fish ever farmed?

                            And does tilapia have a reputation for harboring worms?

                            1 Reply
                            1. re: Perilagu Khan

                              In order, No. Yes. Yes.

                              Basically, if you haven't done something to your fish to sterilize it (i.e. flash freeze it, cook it), you have to potential for worms.

                            2. does haddock have this issue as well?

                              1. Great. I just got my copy of "Fish Without a Doubt" in the mail today. Bleah.

                                1. Whether you shop at the corner market or Whole Foods, Applebees or Per Se, everything worth eating is going to have worms, parasites, bacteria, spider eggs, banana lice, chicken pox, beef cancer, broccoli feces and fish herpes. Hell, last time I was in France, my family was fighting over who got to eat the little Pea Crabs when they turned up in the odd oyster.

                                  My suggestion is to not panic over the little beasties and to go with your gut, literally. As unpleasant as it sounds, your body is an ecosystem and while you don't want to open yourself to all comers, it is likely able to manage perfectly well on its own when you get the odd hitchiker.

                                  23 Replies
                                  1. re: Ernie Diamond

                                    But it's not the health issue that bothers me. Frankly, I don't give a damn about that. What I cannot stomach--so to speak--is a visible worm (dead or alive) on my plate. To me, that is self-evidently repulsive and sufficient reason to forego the offending food item.

                                    PS--I've done some cursory reasearch and it seems that farmed fish are far less likely to contain parasites than wild caught fish. Fish farmers use anti-parasitics in their water and also manage to keep the birds away that are most responsble for introducing vermin into the fish's ecosystem. So at this point my go/no go criterion will be the wild caught/farmed divide.

                                    1. re: Perilagu Khan

                                      I wouldn't bet too heavily on either side. Farmed salmon are famous for having fish lice, whether they're internal or external the close quarters they're raised in boosts the potential exponentially.

                                      1. re: EWSflash

                                        But presumably fish lice would be cleaned off long before the fish reached my shopping cart. I'm not crazy about eating fish that has ever had a parasite, but that is a considerably lesser evil than fish still containing the little bastards, dead or alive.

                                      2. re: Perilagu Khan

                                        I suppose that a fundamental rift will exist between those who would rather eat a chemical-free fish with worms (me) and those who would rather eat a fish treated with "anti-parasitics." Something about that last category smacks of the artificial.

                                        From a health standpoint, if I don't know what the chemical is or how it will affect me, I won't eat it.

                                        1. re: Ernie Diamond

                                          To each his own.

                                          "Artificiality" doesn't cause my gorge to rise, and I'm perfectly willing to swallow the "risk" of occasionally ingesting trace chemicals.

                                          1. re: Perilagu Khan

                                            And yet, one wonders why they're treating them with anti-parasitics... Probably because they're prone to getting parasites... I'd be curious as to how well the treatment works. Most chronic anti-infectives lose effectiveness extremely rapidly. (Granted, I'm more familiar with human anti-infectives, but the principle still holds).

                                            1. re: Indirect Heat

                                              My understanding is that the farmers treat the water rather than the fish themselves.

                                              1. re: Perilagu Khan

                                                Doesn't really matter, if you're putting antibiotics/anti-parasitics in the water or in the animal. They'll lose effectiveness in a relatively short time as mutants crop up that are immune.

                                                And really, I would expect all medications administered to fish would go in the water -any fish vets out there ;-) ?. Rather easier than giving them pills or shots, and not that different from putting it in the food.

                                                1. re: Indirect Heat

                                                  Regardless of efficaciousness or method of administration, at least steps are taken with farmed fish, and I don't think the farmers would be spending the money if it didn't accomplish something. And by accomplish something, I don't mean reassure the parasiphobes like me who have dug into the issue and done a little research.

                                                  1. re: Perilagu Khan

                                                    From what I understand, tilapia in particular are raised in disgusting conditions of filth and excrement. And taste like it. I won't touch it. I don't want to eat chemical laden fish nor do I want that pollution in the waters any more than I want worms crawling on my plate.

                                                    1. re: mcf

                                                      Sounds like a gross exaggeration. I've eaten plenty of tilapia and never has it tasted like "filth and excrement." If it did, I don't think it would be as popular as it is.

                                                      1. re: Perilagu Khan

                                                        Not all, but quite a lot of it has an icky texture and muddy taste. There are discussions about this on these boards.

                                                        1. re: Perilagu Khan

                                                          I have to say I've given up on tilapia after about the 3rd time of trying it and kept getting that horrible taste. This was before I knew anything about its habitat, etc. Can't describe the taste, but yeah, "filth and excrement" sounds just about right. Ick.

                                                          1. re: gloriousfood

                                                            Some of my favourite things live in filth and excrement. Pork. Catfish. Mushrooms.

                                                            Love it!

                                                            1. re: Indirect Heat

                                                              Yes, but not all of those end up tasting like filth and excrement. Not an unimportant distinction, IMO. ;-)

                                                                1. re: mcf

                                                                  Ahhh how foolish of me to have opened this thread! I'm with you MCF about the talapia. Never had it and never will after seeing an episode of Dirtiest Jobs that was at a fish farm. Can't remembr what kind of fish they were raising, but when the fish were harvested and the pond was filthy with fish waste they put talapia in to clean it. Ugh, too much info.

                                                        2. re: Perilagu Khan

                                                          Perilagu, water treatment accomplishes overcrowding and unsanitary conditions in aquaculture to be viable production tools. The reasons fish-farmers medicate their stock is because their methods would be unsustainable otherwise. Don't assume that because a fish is worm-free that it came from a better place. I assure you that wild-caught food is more prone to certain parisites than, say Tyson Chicken but that does not mean that Tyson Chicken is a good product.

                                                          To the point of Tilapia, the reason that it is becoming such a popular fish on restaurant menus is because it can be cheaply and intensively farmed in revolting conditions. I first became aware of the fish when Biosphere II was underway. They were used as a stage in sewage treatment. Basically, all the "grey water" from the toilets was pumped into tanks where tilapia digested solid matter (feces) and allowed the water to be more quickly recycled.

                                                          If swallowing the occasional worm freaks you out, maybe you should reconsider eating meat. It's part of the deal.

                                                          1. re: Ernie Diamond

                                                            Again, couldn't conceivably care less about chemicals and what a fish eats. Those things do not bother me in the SLIGHTEST. I hope I've made myself sufficiently clear on that.

                                                            What does bother me is individual parasites that are large enough to be visible to the naked eye. End of story.

                                                            And that being the case, I will certainly make it a point to patronize farm-raised fish and avoid wild caught. For much the same reason (and because of economics as well) organic vegetables are not on my plate.

                                                        3. re: Indirect Heat

                                                          you are correct.
                                                          fish medications go in the water.

                                                          1. re: Indirect Heat

                                                            The "qualities" of tilapia that makes them so attractive to be farmed is that they grow very fast and they are very hardy. Because they are so hardy, treatments and medications are used minimally - this makes them extremely attractive to farmers in countries where technology is relatively simple.

                                                            They are extremely sensitive to water temperature - typically a warm water fish (another reason they are popular with aquaculturalists in tropical/subtropical zones) - and they require additional aeration in a higher density environment. As long as the water chemistry is kept relatively stable (PH, salinity, etc.) they are pretty happy campers. No, they're not immune to disease and parasites, but compared to most other aquaculture species, they are relatively bulletproof.

                                                          2. re: Perilagu Khan

                                                            Khan - "the farmers treat the water rather than the fish"

                                                            and thereby treat the fish (by that logic I didn't give the cattle BGH, I just put it in the food)

                                                            ehh I don't care, I'd just eat the worms.

                                                  1. one thing you have to remember is that the whole situation of the worms being something that might disgust you now is that before you saw them or heard about them, you ate the fish with no negative apprehensiveness. and for the group talking about tilapia, the same thing. It is called fear and is a learned thing as you get older. When you are a little kid you are bold and dangerous but as you get older you learn that some things are dangerous and you lose the fearless mindset more and more and succumb to doing less and less. If you did it before, no reason to change you habits unless it is life threatening..
                                                    live life now because it is so short and you cant live it after you are dead! lol

                                                    1 Reply
                                                    1. re: calikoala

                                                      >>ive (sic) life now because it is so short and you cant live it after you are dead! lol<<

                                                      The worms will have the last laugh when we die anyway. :)

                                                    2. I just ate at least a half lb. of tilapia after frying it up for some fish sticks the other day - now I'm regretting that! Come to think of it, I did think it tasted like dirt. Mine said "Farm Raised, product of Honduras" - I couldn't find any wild. Yuck! I'm off it now.

                                                      5 Replies
                                                      1. re: elizsafox

                                                        I don't know if wild-caught tilapia is going to be an option here. But in various parts of the world - including Arizona - tilapia are used in waterways to graze on invasive vegetation and detritus. This reduces the likelihood of anaerobic conditions forming as well as stabilizing PH, thereby increasing water quality. I wonder if these fish are ultimately harvested for consumption...

                                                        1. re: bulavinaka

                                                          I've had tilapia in yemen that looked and smelled extremely fresh. It was caught from the south and brought up to the city in the same day .... some of the best fish I've ever had cooked in the special fire burning oven after being smeared with a delicious spice paste.

                                                          I found this thread after reading another super long one last year about the same issue.. but I bought some frozen cod and was looking for some recipes .. now I kinda regret buying it but it's frozen anyway and after thawing I may inspect it and then decide what to do with it.

                                                          I've eaten fish a lot and in many countries, mostly fresh water fish and have NEVER seen a worm so I'm rather surprised to hear how common they are.

                                                          1. re: BamiaWruz

                                                            I prepare a fair amount of white fish at home and have only had one run in with worms. I had purchased a whack of snapper to make fish tacos with on a ski trip. Luckily, everyone else was still hillside as I speedily prepped the fish, removing the worms and disposing of them long before anyone returned. Needless to say, it was don't ask don't tell. And no one was the wiser (or sick). It wasn't a fun job but it didn't turn me off eating the food and it didn't change the taste of it.

                                                            I find both catfish and tilapia can taste muddy, which drives me nuts because when they are good they are quite sublime. I have not experienced any other unpleasant taste to these fish personally.

                                                            1. re: grayelf

                                                              I wish there was a "like" button for this, I'd give you a thumbs up, grayelf.

                                                              But since there isn't, I give you a thumbs up, grayelf!

                                                              1. re: EWSflash

                                                                Why thank you! I'm not sure why this didn't make me squeamish, actually. It's not like I don't get skeeved out by things. Just today I was grimming out over dead leaves stuck to the dahlia stalks I was putting in a bouquet, go figure. Maybe it's because my dad worked for the dept of fisheries for 40 years. Oh wait, that's why I don't eat raw salmon but that's another thread :-).

                                                      2. My best friend's parents owned a seafood restaurant on the coast of New Hampshire. I worked there for a few summers. One of my jobs was to de-worm the cod that was sold fresh. (the things you'll do when you're young!) I would hold the cod up so the ceiling lights would illuminate the flesh, making it somewhat translucent. When a dark or opaque spot was found, I'd slit it open with a knife and scoop out the worm. I found that the darker parts, not always, but often would have worms in them. Or if there was a slight bloody mark there would be a worm. I never came across a piece of cod without worms. GROSS. I have never eaten cod to this day. Of course, the fish we served in meals was never de-wormed. Most fish are wormy. Swordfish is known for worms and they have these long, dark, nasty looking ones. Tuna has them but I didn't find them as often as I did in swordfish.
                                                        We also served/sold haddock, which is very popular in New England. We did not have to de-worm the haddock. Maybe someone else has a different experience, but I never found anything suspect in haddock. Hence, this is the only fish I would every buy for home consumption. I love it.
                                                        Thanks for the info on the tilapia. That is a fish which I have started eating. I can't get fresh haddock in Arizona - won't eat frozen - so I've turned to tilapia. I don't like my animals to live unhappy or unhealthy lives before I eat them ( I know, I know, the logic is flawed.....my meat guilt isn't always logical).

                                                        1. I knew I never should have opened this thread....I ordered fried (fresh) cod tacos at Serpentine (a really nice restaurant in San Francisco) and I couldn't stop thinking that there might be cooked worms in the cod. I only ate 1 bite and let my friend eat the rest -- of course, I did not tell him about this thread!!!! (I ate the delicious veg risotto, instead.)

                                                          1 Reply
                                                          1. I worked in seafood processing in Alaska. Cod fish go thru a process called candling. We have tables with white plexiglass tops with flouresent lights under them, the cod fillets are placed on the candling table, the light shines thru the fillets and any worms, or bones are easily seen and removed. Once frozen to -20deg f or cooked thru to above 135deg f these worms are killed, so unless you are eating fresh cod, or other seafood raw you should not have any troubles. These worms are normal just not appetizing.

                                                            5 Replies
                                                            1. re: depotcook

                                                              Do you know if candling is done to other types of fish as well?

                                                              1. re: Perilagu Khan

                                                                Cod as in True Cod or Grey Cod, Pollock, and I think some of the flat fishes like flounder. Thick fillets as in Halibut or in the case with salmon the light will not pass thru the fillet, so you would not be able to see any bones or worms in the middle of the flesh.

                                                                1. re: depotcook

                                                                  Thank you. Looks like it's a fairly complicated process knowing which fish is "safe," if the parasites bother you in the first place, that is.

                                                                  1. re: Perilagu Khan

                                                                    Like pretty much anything when properly cooked the risks are very very slight.
                                                                    I tend to buy seafood from American suppliers. Seafood processed here is inspected by state and fed. inspectors. This may not add too much comfort but is far far better than what goes on in some other countries.
                                                                    Not all imported seafood is bad just know where it is comming from, how it is caught and processed, ask questions, look at the lables.

                                                                    1. re: depotcook

                                                                      Do you know anything about sole? Is it likely to be one of the cleaner fishes?

                                                              1. My grand mother was a Chef- She told me "all fish have worms" and flounder, Halibut and that all "bottom fish" have the most- She Would first slap the fish filet against a cutting board" hard
                                                                and the worms would rise I could see them . She would then scrape them clean off with the edge of her wide knife. Then into the hot frying pan would go the fish.
                                                                Bon appetite

                                                                3 Replies
                                                                1. re: ArtMetal

                                                                  Someone in this thread or one like it worked as a fish processor and said that the only fish that they'd never seen a worm in was haddock. I LOVE haddock more than ever since then. :-)

                                                                  I hold fish filets over bright lights to visualize any coiled worms. So far, so good; maybe my fish were properly candled before sale.

                                                                  1. re: mcf

                                                                    Grouper also has worms, (fluke worms), but they are usually very small and when cooked they seem to disappear. I have found Red Grouper to be the wormiest!! and Yellow edge the least in the "critter count".......

                                                                    1. re: ospreycove

                                                                      Fortunately, I don't like grouper. :-)