These ugly creatures attach themselves to intestinal walls, then suck on tissues and blood, causing the host to suffer from iron deficiency anemia. When we are always hungry, we may jokingly say that we have tapeworms. However, there is nothing funny about tapeworms. These huge parasites may be more than 30 feet long and are capable of producing a million plus eggs a day. Tapeworms consume so much food that the host may actually be hungry all the time, yet may appear obese because of tapeworm-induced water retention.
Pinworms are extremely common intestinal parasites.
Once pinworms are snugly ensconced inside the human body, they crawl outside the anus at night, causing severe itching, and then lay their eggs on bedding or sleep wear. They focus all their energies on eating and reproducing. Getting rid of them is difficult. Not all parasites are menacing. Some living things that park themselves on or in our bodies actually perform a service.