My great aunt used to always say that my brother ate like he had a tapeworm, meaning he was constantly feeding his face but stayed just skin and bones. I know it's just a saying, but I keep hearing people say a tapeworm can actually help you lose weight. So, for real, do tapeworms make you skinny?
That's an excellent question--the answer to which the contestants from America's Next Top Model await with hungry anticipation. Sorry to disappoint them, but they should not count body sculpting as a side benefit of a parasite infection. Taking weigh-control advice from the rumor mill is always a bad idea, though I suppose the simplicity of a friendly little tapeworm might appeal to some. After all, many of the supermodel wannabes long to be so skinny that they'd need to have deodorant specially made to fit Chapstick containers.
Tapeworm infection does have physical effects, but allowing you to eat all you want without gaining weight is not one of them. Human infection with a fish tapeworm, for example, can lead to pernicious anemia as the worm steals vitamin B12 from your food before your intestine can absorb it. Tapeworms acquired from contaminated beef or pork can also cause malnutrition; the parasites themselves take many nutrients from the predigested foodstuffs that conveniently wash over them. One or two worms usually keep a low profile and cause few noticeable symptoms, though abdominal pain, diarrhea and nausea can sometimes be present. Still, it's better than eating alone.
The distinction of largest human parasite falls not to MSNBC's Tucker Carlson, but to these ribbon-shaped beasts called cestodes. Holding fast to the gut wall by hooks or suckers, a single tapeworm can be as long as 30 feet and live for two decades. As flat as they are, yards and yards of worm is still a tight fit in a small intestine. Multiply that by the number of tapeworms in some infestations and one can quickly see how intestinal blockages can occur.
Exposure in humans usually begins with eating muscle tissue (fish, beef, pork) harboring tiny cysts containing the worm's larval form. Once released, the larva attaches itself to the intestine where it grows a long strip of postage-stamp-style packets called proglottids--each containing up to 100,000 fertilized eggs. As the tapeworm matures, groups of these packets break off and are passed through the feces with each egg hoping to be ingested by a passing pig or cow. For some people, the first sign of infection is the odd sensation of a little wiggly ribbon passing along with the contents of their bowels. This phenomenon, clearly visible in puppies, may be the reason so many are named Scooter.
The suggestion that infection could help weight loss likely began with advertisements for tapeworm diet pills published in the 1920s. These were doubtless more gimmick than fact. Helping the rumblings along was an almost certainly fabricated story regarding the opera soprano Maria Callas' worm-assisted weight control plan. More recently came a 2004 issue of Weekly World News, the paper of record for alien invasions. This article announced an implausible chain of weight loss centers based on ingestion of tapeworm larvae. My favorite quote: "I feel like I have my own little diet coach deep down inside."
Yes, it's all myth, though the mere thought of harboring tapeworms makes me lose my own appetite (my most efficient hunger killer is to TiVo Tucker Carlson). But if you wish to avoid a real infection, it is actually fairly easy. Freezing beef or pork for 12 hours--fish for 24--will kill any larvae within the muscle tissue. Cooking meat to a temperature of 150 degrees Fahrenheit will do the same. Unfortunately, smoking or drying won't kill the parasites, so use caution with jerky of unknown origin. And, since the fish tapeworm is present only in freshwater fish, eating sushi is quite safe unless it's Alabama Earl's Spicy Bass Roll. Ingestion of the actual eggs of some tapeworms can also be dangerous, giving moms yet another way to frighten the kids into washing their hands.
One small comfort is that you cannot contract these intestinal freeloaders from Scooter the dog or Buttlick the cat; their tapeworms are species-specific. Of less solace to aspiring fashion models may be that despite their endeavor to look like a tapeworm (i.e. thin and flat), they will have to hire a more traditional team of diet coaches, personal trainers and managers. That might be too bad: Like the parasites, once these guys get their hooks into you, they're nearly as troublesome to remove.