4. Eating tapeworms
As disgusting as this may sound, people still do it. Tapeworms, once inside the body, basically eats your food and does not let them digest. Apart from causing severe abdominal pain, these tapeworms tend to grow 30 feet inside your stomach. A woman from Iowa swallowed a tapeworm that she bought from the internet. Luckily, she went to the doctor after some excruciating pain.