A microscopic close-up of the individual segments (proglottids) of a tapeworm's body.

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Tapeworm Myths

There are a few tapeworm legends floating around in addition to the weight-loss one, so let's clear some of those up first. One is that you can get rid of a tapeworm by coaxing it out with a bowl of milk and cookies placed near your mouth. Not true. A tapeworm is not Santa Claus, and not only does it live in your intestine -- with a stomach and esophagus between it and anything near your mouth -- but it doesn't even have any sensory organs that would allow it to detect the presence of food. Remember, this is a very simple creature. It can't smell or see. This is the same reason that putting some enticing food near the other end of your digestive tract won't draw out a tapeworm either. If you have a tapeworm, simply take your pill and let nature take its course.

­Opera singer Maria Callas was rumored to have used a tapeworm to achieve a remarkable loss of weight in the mid 1950s. She did, in fact, lose more than 60 pounds over several months. She was also known to have contracted a tapeworm at some point in her life. However, the two incidents are probably unconnected. Callas enjoyed rare steak, so she probably got her tapeworm accidentally. These two aspects of her life were jumbled into a persistent rumor.

There is evidence of advertising, from the late 19th and early 20th century, hawking "sanitized tapeworms" to help women maintain a slim figure. Whether the pills sold actually contained tapeworms or whether women actually ingested them hoping to acquire a tapeworm is difficult to verify. Such a pill would likely contain the cyst part of the tapeworm's lifecycle, but one would imagine that cultivating a large supply of these would make for a rather unpleasant day's work. It seems unlikely, but there's also a good chance that somewhere in the long, strange history of humanity, someone somewhere did try using a tapeworm to lose weight. So, the answer to the question, "Did it happen?" is most likely yes, but it was probably never widespread.

That leaves us with just a few more interesting questions. What happens to your body when you have a tapeworm? Do the pounds just melt away? Can you stuff your face with all manner of delicious, unhealthy foods and get off consequence-free? Well, not exactly. For one thing, tapeworms are not large enough to absorb all the calories a human takes in. If your diet is already limited, the tapeworm could steal enough from you to cause malnutrition. If you're chowing-down on carbs, both you and the tapeworm will probably pack on the pounds. In most cases, a tapeworm infection is completely symptom-free. In fact, you might never know you have one until a proglottid makes its presence known in your toilet.

Some tapeworm hosts do suffer from intestinal discomfort or diarrhea. And some also experience reduced appetite, which could lead to weight loss. However, we can assure you that simply reading about tapeworms can cause a similar loss of appetite, so more drastic measures might not be necessary. But even if a tapeworm did trim some pounds, it still wouldn't be a good way to lose weight.

For most people, the goal of losing weight is to look better. However, as a tapeworm steals certain vitamins from your body, notably vitamin B12, you'll suffer ill health due to a shortage of those nutrients. Sure, you might slim down, but no one is going to be impressed with your sickly appearance. If that weren't enough, there's always ascites. Ascites is a condition in which the body's immune response to a parasitic infection leads to a build-up of fluid in the abdominal cavity. This manifests itself physically as a swollen, distended belly. Not exactly the intended result of a tapeworm diet plan.

And don't forget about good old cysticercosis, with the brain damage, blindness and possible death. Given this information, we think it's safe to say that if you really want to lose some weight, eat less and ride your bike.

If you were fascinated (or possibly even nauseated) by these parasites, then you might want to take a look at a few similar articles and other related links on the following page.