The cockroach that I observed is more important as a pest problem than as an important link in the food chain. Other species do provide nourishment for certain insects. In particular, spiders are its natural enemy. However, they are too sluggish to really inflict harm. Frogs, toads, and salamanders are more effective predators.
Lizards are also very successful in catching the roach.
In some parts of the world the lizard is kept as a pet just to keep the house clean of roaches. Humans have also used the cockroach as a source of nourishment and for its medicinal value. The roach, as a pest, is responsible for millions of dollars of spoiled food, pesticides, and damage to the environment from these pesticides. The non-deadly diseases they cause such as Salmonella, staph. and strep. have contributed to its being such a despised insect. Recent discoveries have suggested that the skin molts of the cockroach have caused allergic reactions and asthmatic conditions in some children who live in poor urban areas.