How Much Do Cockroaches Eat?

If you have ever had to deal with cockroaches then you know that they are quick to move in and difficult to get rid of. This is largely due to their unique eating habits, and their ability to consume a larger variety of food.

Cockroaches eat about as much as half their weight per day. This amount varies depending on the variety of cockroaches.

  • Cockroaches are omnivorous scavengers, and they will eat almost anything they find.
  • Cockroaches can go up to a month without eating, but they only last a week without water.
  • Cockroaches will eat almost anything they can access, including fresh food, pantry food, trash, and even household items.
  • Cockroaches are able to eat so many foods because of the unique symbiotic relationships they have evolved to have.

How Much Cockroaches Eat

Cockroaches are omnivorous scavengers, so they are constantly on the search for food to eat. Luckily for them, they are capable of eating almost anything they come in contact with.

While there is little information available on the exact amount that cockroaches can eat, it is estimated that they consume about half their weight per day.

The household varieties of cockroaches are not very large, and most do not weigh more than 30 grams. Cockroaches do not exist on their own, and their colonies can range from a few dozen to hundreds and thousands of cockroaches.

Females can lay eggs in bundles from 4 to 30, so these insects can grow their colonies quickly. While one cockroach may not seem like it makes a dent when it comes to eating, considering the entire colony paints another picture.

How Long Can Cockroaches Go Without Eating?

Cockroaches can go up to a month without eating. This is part of the reason that cockroaches, who have multiple nervous centers, can live so long without their head.

This extended period is largely due to how the metabolic system of a cockroach is set up. While cockroaches are not necessarily similar to creatures like snakes or lizards, their metabolisms work in similar ways.

How Cockroaches Can Go So Long Without Eating

Cockroaches are cold-blooded insects, also known as ectotherms, and they share characteristics with other creatures in the same category.

These insects do not retain their body heat, and their energy is spent in other ways. This is a major pull of energy for warm-blooded (endothermic) creatures, but cockroaches do not require the additional energy for this task.

This gives them the ability to go longer without consuming energy. Cockroaches can slow down their metabolism when it is cold outside, but this also limits their movement during colder months.

Can You Starve a Cockroach?

It is highly unlikely that you could starve a cockroach. These insects have thousands of years of instinctual evolution that help them find any crumb or scrab that they could possibly eat and live off of, and they do not require much food to keep living.

The more likely scenario is dehydrating the cockroaches. They can only survive one week without water, and they rely on the humidity for processes like molting to proceed without issue.

A roach will suffer more in a home that gets rid of moisture sources like leaky pipes or other standing water than it would in a home where all the food was put away.

Cockroaches do not only eat what humans consider “edible”, and it would be nearly impossible to separate them from everything they eat.

What do Cockroaches Eat?

Cockroaches can eat nearly anything they come in contact with, regardless of whether humans consider it food or not. Their diets primarily consist of:

  • Fresh food
  • Pantry food
  • Leftovers
  • Kitchen messes/garbage
  • Pet food
  • Household items like books or cardboard boxes
  • Organic matter (both outside and inside)

While their diet is not limited by much, cockroaches do prefer food that is easier for them to eat. They have weak jaws and sideways moving mandibles, so they opt for smaller, softer food whenever it is available.

Cockroaches are also great at finding food using their sense of smell, so they can scope out the slightest crumbs a vacuum or broom managed to miss.

Fresh Food

Despite a reputation for dumpster diving, cockroaches almost always go for fresh food when it is available. This includes:

  • Fruits
  • Vegetables
  • Opened food left out
  • Cooked food
  • Animal proteins
  • Cheese

Cockroaches also show a preference for moldy or fermented food, including alcoholic beverages. American Cockroaches have a particular attraction to alcoholic beverages like beer.

Fresh foods are easier for cockroaches to eat, and they may have a stronger scent that makes them easier for cockroaches to seek out.

Pantry Food

Even packaged food in your pantry can be a feast for cockroaches. They prefer sweets and starches, and you might find them snacking on:

  • Pasta
  • Sugar
  • Rice
  • Cereal
  • Chips

While cockroaches have weaker jaws, they are still capable of chewing through the paper, cardboard, or thin plastic that most pantry goods are stored in.

This is not likely to happen, especially if roaches have access to food in other areas, but any food that appears to be tampered with should be disposed of.

If this is an issue, transferring food to thicker plastic or glass containers can be a more difficult barrier for roaches.


Cockroaches love when they have easy access to leftovers, and leaving out plates of food or dirty pots, pans, and utensils is likely to attract the colony.

In most cases, sealing up leftovers and putting them in the fridge should suffice to deter roaches from pursuing the food. 

Using food storage containers is more effective than methods like cling wrap or aluminum foil.

Cockroaches can fit through small cracks and slivers by flattening their exoskeletons, and they can easily get through the gaps on these wraps.

Kitchen Messes

Kitchen messes like food spills or splatters give cockroaches an easy opportunity to eat when they are not cleaned up.

Cockroaches will also seek out food in the sink, including unwashed dishes. They will even pursue any leftover food that is caught in the sink strainer, benefitting from the moisture that has accumulated in the area.

Cockroaches can find crumbs that you did not even know existed, the kind that is still there after sweeping and vacuuming.

Cockroaches, even the flying varieties, spend most of their time searching for food on the ground. This gives them a better chance of discovering crumbs stuck in the grout or carpet fibers, and they quickly eat these pieces up.

Pet Food

Pet owners that constantly offer food to their companions are also leaving an endless supply of food for the cockroaches in their homes.

Whether this is kibble, wet food, or home-cooked varieties, most pet meals are high in protein and easy for cockroaches to detect through smell.

A bowl of food is basically a mountain of sustenance for a cockroach and even better if it is always replenished.

Cockroaches will easily sniff out and find their way into bags of pet food, even if they are folded over and clipped using a bag clip. Many pet owners opt for airtight containers to help combat insect infestations in their pet food.

Even if you do not leave food out for your pets, the crumbs and oils leftover in their dish can be enough to encourage the roaches in the home.

Other Household Items

Cockroaches can digest food that humans are not able to, including cellulose. This means that a cockroach can find food in many household items, including:

  • Paper
  • Clothing
  • Newspapers
  • Book bindings
  • Stored documents
  • Cardboard boxes
  • Glue on wallpaper and stamps

These are not their go-to sources for food, but cockroaches can make food out of these materials easily.

Organic Matter

Apart from the organic matter found in the foods of your kitchen and pantry, cockroaches can be found eating outdoor materials such as:

  • Piles of leafs
  • Twigs
  • Dead trees
  • Decaying material

In the home, cockroaches are even known to eat materials like skin flakes, hair, and fingernails. They prefer these items post-shed, so there is little need to worry about cockroaches trying to take a bite from the source.

In drastic circumstances, cockroaches have been known to eat each other, but this happens more as a last resort than anything else. 

How Can Cockroaches Eat Such a Wide Variety of Food?

Cockroaches are believed to have existed for about 300 million years, and they were likely residents of the supercontinent Pangea.

They have spent this time surviving and evolving, and this has led to their ability to eat a greater variety of foods.

Part of this is thanks to the symbiotic relationship cockroaches have with the bacteria in their digestive systems.

The bacteria use the cockroaches as a host, and in return, they provide the nutrients necessary to digest many of the foods that cockroaches eat.

A look into the genome of American Cockroaches revealed that a major portion was dedicated to metabolizing toxic or dangerous material that would take out other creatures.


Cockroaches do not eat a lot of food on their own, but they live in colonies sizable enough to make a dent in any food source. 

Cockroaches can live off small amounts of food for longer periods, and they can eat just about anything. These are hardy creatures designed for survival, and they are not likely to die off anytime soon.

Alright, that’s it for this article, here are a few hand-selected articles that you might also find interesting reads:

Why Do I Have Cockroaches in My Home?

11 Tips to Prevent American Cockroaches

15 Unusual Facts about Cockroaches that will Keep you up at Night

Steve Foster

Mad about bugs and wanting to publish as many articles as I can to help educate people about these amazing beautiful creatures! For more info check out my about page

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