Why can you live without food at home? Experts reveal that a factor is more important than food for cockroaches

 8:44am, 13 June 2025

"Ah! There are cockroaches!" After screaming, they chased and beat them. When cockroaches appeared in the home environment, it was uneasy; and cockroaches appeared in restaurants, night markets and other places were even more important to food safety.

Especially when summer comes, not only will all be prosperous and changing, but it is also a terrifying season for cockroach breeding. Taiwan's humid and hot climate is just right for cockroaches to grow. Whether it is large cockroaches, small cockroaches, flying cockroaches, German cockroaches, American cockroaches, etc., it makes many people who are afraid of cockroaches tremble in the fight, fearing that a negligence will cause the terrifying figures of cockroaches to appear in the room.

Many people have this kind of trouble, even if they think cockroaches are endless; we know that there are currently more than 4,000 cockroaches around the world, and there are nearly 80 native cockroaches in Taiwan, including American cockroaches and German cockroaches. The German cockroaches have smaller body shapes and do not leave the kitchen; the American cockroaches have larger body shapes and crawl into the house through channels, mainly without being in the washing room.

In addition to its amazing reproductive ability, cockroaches are also living fossils with strong vitality. They can survive in a bad environment with extremely poor conditions. However, his unhappy appearance and the body that carries bacteria still change the color of many people. If there are cockroaches in the room, it will make people unable to sleep all night.

Q: My family lives in a high-rise building. Where did the cockroaches come in?

In addition to passing through drainage holes in kitchens or showers, cockroaches can also move from one place to another through crawling under doors or through gaps in pipes and walls. However, some are human negligence that makes cockroaches accidentally get into the home by catching a car such as a paper box. The feeding distance of German cockroaches is generally 3 meters, while the feeding distance of American cockroaches is 100 meters away. Even in a environment where food resources are scarce, their feeding distance will be even longer.

Q: Can blocking the drainage hole at night prevent cockroaches from appearing?

If the drainage hole in the home is blocked, it may be possible to reduce the discharge of some cockroaches, but in addition to the drainage hole, cockroaches may still use other methods to enter the home.

Q: Can you put something that cockroaches don’t like in the drain hole?

External transmission can pour sausage, vinegar, and hot water into the drainage hole, but in fact the effect is limited. In fact, there are many connections in the pipeline, which can still provide space for cockroaches to hide.

Q: The food and garbage at home are collected, why are there still cockroaches?

Where cockroaches don't come out are mostly small drops of water in leaky water heads or pipes, condensation on sinks or pumping buckets, humidity around the commercial dishwashing area, and even moisture under kitchen sinks. Therefore, for cockroaches, in addition to food, the water limiting factor is actually much greater than food.

Q: Do you hear that cockroaches like paper products, and they still eat the follow-up of the paper box?

Paper products are not only the food source of cockroaches, but especially damp paper products are also one of the channels for cockroaches to obtain moisture. The damp paperboard has been in the rotten process, which makes cockroaches easy to eat and digest. Cockroaches can eat from almost any organic substance, and they can eat cockroaches, spit out, and even their companions.

Q: What smells or things do cockroaches don’t like? What can I use to drive cockroaches?

Strong fragrance generally has a somewhat avoidant effect on worms, including cockroaches. For example, the smell of harsh herbs and spices, including cinnamon, thyme, role, mint and garlic, etc., but the effect is still limited and short.

Q: When using commercially available cockroach medicine, it is recommended to use cockroach houses or gels. Should you pay attention to using it?

It is recommended that the use of cockroach houses is more effective, safe, non-toxic and easy to operate. They can be placed in the corners of the wall at ordinary times, but the effect may be only to kill cockroaches that come out to eat.

As for the effect of gels, it may damage the entire population, especially those gels using ingredients such as fempin, indec, emethosone, and dydamine, which are a chronic gastric toxicant. After cockroaches are eaten, they can return to the nest to transmit stomach poison to other cockroaches for eating, and their excrement or poisoned cockroach bodies may also cause the death of other cockroaches.

It is recommended that the drug should be applied in the cleavage, wall corners, and gaps. However, long-term use of gluten may also lead to anti-pharmaceutical or behavioral resistance, resulting in the failure of cockroach gel agent.

Consultation/Liang Guowen, Associate Professor of Kunjia Department of Zhongxing University, Editor of Responsible Editor: Gu Zihuan