What Do Roaches Eat?

  • Written By Dan Edwards on August 1, 2018
    Last Updated: November 25, 2020

Cockroaches are creatures that have been around for millions of years, but are definitely not what we want to see around our home. Not only do these pests make us feel uncomfortable, they also carry bacteria and diseases. Finding out what cockroaches eat can help us to understand why they love invading our homes.

There’s not much worse than the thought of these insects running around the home. They climb onto furniture, run across our carpets, and worst of all—can feed off of us or our pets. In this article, we will thoroughly explore the bizarre eating habits of cockroaches.

What Do Cockroaches Eat?

There are more than 3500 species of cockroaches worldwide, but only around 50 to 60 of these are found in the US. From those species, we only need to concern ourselves with a few of them being considered as pests to us.

These are:

  • American cockroach
  • Oriental cockroach
  • Brown-banded cockroach
  • German cockroach
  • Pennsylvania wood cockroach

These are the species that are likely to invade our homes. The most common one being the German cockroach. German cockroaches have been residing in human shelters since the ancient times, due to the fact that they cannot survive severe cold climates. This particular species of roach has now populated much of the world as a result of human travel.

Cockroaches are omnivores, much the same as humans are. Like us, they eat food of either plant or animal origin. The difference is they aren’t as fussy as humans and will eat anything, including rotting food.

Feeding time for roaches is at night, when the lights are out and all is quiet. You will sometimes see them in the day, but this is quite rare. They are generally in their hiding places during daylight, waiting for nightfall so they can feed undisturbed by humans.

Cockroaches are resourceful eaters, and as long as they can find some organic matter, they will eat it. This means they don’t eat items made from plastics or metals, yet they will eat wood.

Roaches have the same taste as humans do for food. That is the reason why you may find them in kitchens, restaurants, and food storage areas.

These are also the places in which you’re most likely to find cockroach fecal matter, too.

Although cockroaches aren’t that fussy, they do have their favorite types of food. They prefer to eat proteins, starchy foods and sweets. These would be foods such as:

  • Meat
  • Potatoes
  • Pasta
  • Sugary and sweet foods

Other items they favor are food products which ferment or go moldy, like cheeses. If you make yourself a sandwich at night, be sure to clear those crumbs away. For a cockroach, this would be a gourmet meal of leftovers to feed on from your counter-top.

If their preferences aren’t on offer, that still won’t stop them. Cockroaches will happily sample any available cuisine they can find.

If there is any decaying matter around, this will spark their appetite. Nevertheless, cockroaches can make a meal out of almost anything. As long as the potential food source contains proteins that are rich in lipids, as well as carbohydrates, they won’t starve. The unusual items that could be considered as edible material to a cockroach are:

  • Garbage
  • Human waste
  • Plants
  • Fat/grease
  • Soap
  • Cosmetics

With such a varied palate, it’s easy to see why these pests invade our homes, and even our cars. There are many offerings available to them, even in the cleanest of establishments. Another food source which attracts roaches is pet food. How many people who own dogs or cats will leave a dish of food down for their beloved pets? While you don’t want your pet to go hungry, you also don’t want to gain roaches as pets either.

An important part of a cockroach’s diet is water. This is why sources of water are attractive areas to them.

What Do Roaches Do If There Is No Natural Food Around?

A cockroach’s perspective on food is very different from ours, even though they are omnivores, just like us. They can find certain items to be viable additions to their diet, that we would never even contemplate.

If we wanted more starch in our diets, we would think about ingesting carbohydrates, such as potatoes, pasta, or bread. A cockroach takes a different angle, and would consider things like:

  • Paper
  • Glue from book bindings
  • Wallpaper paste
  • Glue from stamps or envelopes

When looking to add protein to their diet, they might opt for dead insects or human hair and fingernails. Cockroaches may also feed on animal skin, including leather items in the home, although not their ideal choice.

If the supply of food becomes sparse, they may even consider cannibalism and eat their young. In very rare circumstances, they have even bitten humans. This would be rare, however, and only if infestations have reached catastrophic levels.

Cockroaches aren’t equipped with the mouthparts to be able to feed on humans. Their mouthparts are primitive compared to some other species of insect.

These mouthparts allow them to manage their diet by chewing and carrying their food. If they tried to bite a human, it would prove difficult to pierce the skin. Nevertheless, they will feed on dead skin, eyelashes, and callouses from the human body.

How Long Can Roaches Live Without Feeding?

It would be a very rare occurrence for an expert scavenger like a cockroach, not to find a food source. The chances of them running out of food is very low. Outdoors, they will even eat dead wood or rotting plants.

If roaches are in sewers, there would be ample amounts of waste for them—both human and environmental. Unless the roach infestation exceeds the resources, a shortage of food is highly unlikely.

If the situation did get so bad that food wasn’t in ample supply, there wouldn’t be too much of a problem in the short term. Generally, the lifespan of a cockroach is around a year. As they are cold-blooded insects, most species of roach can survive for a month or more without food. However, to do this, they must have a supply of water.

If roaches were to have food but not water, then their life expectancy would be somewhat reduced. Without water, cockroaches could only survive for up to a week. This is why you will generally find them living in dark and moist places. Water is the most important source and can help them survive for long periods of time.

Cockroaches In House

These insects are very cunning and resilient. It is easy to see why it can be hard to keep on top of infestations. They hide in cracks and crevices or behind walls, and eat pretty much anything, so they are a tricky enemy to deal with. 


As you can see, the prospect of eliminating cockroaches could prove difficult. It’s pretty much impossible to rid your home of all food sources for these hungry creatures. These insects are extremely resourceful. Not only are they experts when it comes to finding food, but they can also live without eating for long periods, if necessary.

It would also be impractical to remove the water sources which attract them, as these are vital to humans too. The fact that they have been around for millions of years proves how adaptable they are. You may need professional help to destroy an infestation, yet knowing what cockroaches eat can at least help you to identify what is attracting them to your home.