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Foods That Are Poisonous to Your Rat

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** experienced pet rat owner and enthusiast ** content written 2011, content updated 2012, photos updated 2020


Do You Know What NOT to Feed Pet Rats?

Who doesn't enjoy giving their pet rats treats?

You can find great treats from the bird and small animals aisles at the local pet store, but you can also share foods from your dinner plate. (My husband is a really good cook; I want little Rattie to try some, too!) But not all foods are safe for feeding pet rats, though. Do you know which foods are safe, which foods should be fed only once in a while, and which foods are poisonous to pet rats?

Below, you'll find answers!

Answer: False!

Rats are scavengers. In the wild they eat extremely cautiously and generally stick to foods they know are safe. But when foods are scarce, rats are forced to try new foods. A single rat samples a small bit of a new food and returns to the pack where the rest of the rats can inspect the tester's muzzle, breath, and well-being. The pack then decides if the food is safe. If a food is determined unsafe, the rats avoid it indefinitely. These preferences are shared throughout the pack and passed to offspring.

Pet rats, on the other hand, have learned to trust humans and are not cautious like their wild brothers. Pet rats will generally take food from the dish or the kitchen floor without a second's hesitation. This is why it's extremely important to control what foods your pet comes into contact with.


Foods Rats Should Eat Only in Small Amounts

  • Avocado: The skin and pit of the avocado are toxic. Don't feed them the flesh near the skin and pit, either. For the safest bet, skip avocado altogether.
  • Carbonated Beverages: Rats can't burp, so carbonated beverages can cause a lot of discomfort.
  • Chocolate: In large doses, chocolate is like a poison to some animals, causing foaming at the mouth, diarrhea, seizures, and death. Evidence has not proven this applies to rats, however many vets still caution its consumption in large doses. Dark chocolate, with its higher caffeine content, is especially cautioned.
  • Citrus Fruits: D-limonene, a compound in citrus skin that also contaminates the juice during squeezing, can cause kidney damage and kidney cancer in male rats. Clean citrus fruit after peeling it to remove remaining oil, or skip the fruit all together for your safest bet.
  • Mango: Like citrus fruits, mango skin contains d-limonene.
  • Peanuts
  • Potato: Potato flesh (not the skin or eyes) is safe unless it's green. This green contains the toxin solanine, so be careful not to feed your rat any potato that is green.
  • Sugary Foods
  • Fatty Meats and Foods: Continuous excessive fat consumption can cause, at best, oily fur and at worst, diarrhea, fatty liver disease, and death. Excess fat also interferes with nutrient absorption, including the digestion of calcium.
  • Sticky Foods: Sticky foods, especially thick ones like peanut butter, can cause choking. Cut peanut butter and similar foods with a liquid and supervise eating.
  • Fluorinated and/or Chlorinated Water: Fluorine can cause brain damage in rats, and chlorine is also toxic. Only use filtered tap water or non-fluorinated bottled water unless unfiltered tap is all that is available.
Q: Is blue cheese good for your rat? A: No!

Q: Is blue cheese good for your rat? A: No!

Foods You Should Never Feed Your Rat

  • Alcohol: Some curious pets like to drink out of glasses, so keep wine and other alcoholic beverages inaccessible. Alcohol depresses organ systems and can cause death.
  • Green Bananas: Green bananas inhibit starch-digesting enzymes.
  • Raw or Raw/Dried Beans: Share well-cooked beans with your rat but never uncooked or dry beans which contain hemagglutinin, which is a very toxic anti-nutrient that destroys vitamin A and enzymes needed to digest protein and starches. This causes clumping of red blood cells.
  • Blue Cheese: The mold in blue cheeses is toxic to rats.
  • Caffeine: Keep caffeinated beverages such as soda and tea out of rat reach. Consumption can lead to cardiac malfunction, fast heartbeat, arrhythmia, and cardiac arrest.
  • Citrus Peels: D-limonene in the peels can cause kidney damage and kidney cancer in male rats.
  • Raw/Dried Corn: Dried corn can contain high levels of fungal contaminates shown to cause liver cancer.
  • Insects: Insects may carry internal parasites and diseases.
  • Licorice: Possibly causes neurological poisoning.
  • Potato Eyes and Skin; Green Potato: Plants in the nightshade family have healthy fruits but toxic leaves and stems. Potatoes, a member of this family, are safe unless green appears near the skin. Always keep your rat away from potato eyes and skin or potato that is green or near this green color.
  • Raw Sweet Potato: Raw sweet potato contains compounds that form cyanide in the stomach.
  • Spoiled Produce: Spoiled produce, or even produce and other foods not visibly spoiled but still old, contain deadly toxins and can have unseen bacteria and mold spores that cause digestive upset and possibly death.
Don't feed dried or uncooked beans to your pet rat!

Don't feed dried or uncooked beans to your pet rat!

Foods Rats Can Eat When Cooked (Not Raw)

  • Artichokes
  • Beans
  • Brussels Sprouts
  • Corn
  • Egg
  • Red Cabbage
  • Sweet Potato
  • Meat
Oleander: Many house plants are poisonous to rats (and people)!

Oleander: Many house plants are poisonous to rats (and people)!

Plants That Are Poisonous to Rats

  • Amaryllis
  • Azalea
  • Christmas Rose
  • Chrysanthemum
  • Crocus
  • Cyclamen
  • Dieffenbachia
  • Geranium
  • Hyacinth
  • Hydrangea
  • Ivy
  • Lily of the Valley
  • Mistletoe
  • Narcissus
  • Plants in the Nightshade Family
  • Oleander
  • Poinsettia
  • Primrose
  • Tomato (green only, not fruit)

Plants in the nightshade family have healthy fruits but toxic leaves and stems, which contain the toxin solanine.

What Makes a Healthy, Balanced Diet for a Rat?

Every species on our planet has a body with different requirements, and rats are no exception. Like humans, rats need a diet with lots of variety; different nutrients come from different foods, after all. Plus, we'd all get bored eating the same thing every day. But unlike humans, rats need a very different proportion of carbs, fat, and protein.

According to, pet rats need a diet consisting of 75–80% carbohydrates (think whole grains, fruits, and veggies), 12–20% protein (think nuts, cooked beans, and meat), and around 4–6% fat (think . . . well . . . nuts and meat).

Additionally, approximately 80% of a pet rat's nutrition should come from a commercial rat food (hamster or mice foods don't cut it) and the remaining 20% from fresh fruits, veggies, and treats.

Rats also require a supplement of animal protein. Technically, not all types of rats need any animal protein at all. Pet rats were bred from brown rats, though, which do. Try giving little Susie a piece of your well-cooked grilled chicken or Nibbler a piece of hard-boiled egg. Not too often, though! Too much animal protein can lead to skin problems and allergies.

Quality lab block products specifically formulated for rats are great because they provide a balanced diet and something hard on which to gnaw. Multi-colored rat mixes are healthy, too, as long as you wait for your rats to eat all the food in the dish before you replace it; otherwise, rats will pick and choose their favorite pieces and leave the rest, creating a nutrition imbalance.

Of course, like human baby formula, we can't be certain these lab formulas are perfect, so it's imperative to supplement with fresh foods. Additionally, consider the most recent research on GMO corn and soy and non-organic ingredients before choosing a particular brand of lab block.


Buscis, Gerry and Somerville, Barbara. (2000). Training Your Pet Rat (Training Your Pet Series). Barron's Educational Series.

Ducommum, Debbie. (2002). Rats: Practical, Accurate Advice from the Expert (Complete Care Made Easy). Irvine, California: BowTie Press.

Gerd, Ludwig. (2010). My Rat (My Pet Series). Barron's Educational Series.

Rat & Mouse Club of America: Can I Make My Own Rat/Mouse Diet?

Rat & Mouse Club of America: Chocolate and Rats

Rat Care Guide: Diet

This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.

© 2011 shandigp

Readers' Thoughts and Comments

Kristina on July 07, 2020:

I read what you wrote, and I appreciate all the information, but why are our commercially available rat treats made with dried corn kernels in them?

Jessica Bamford on April 07, 2020:

Just a quick add on to the comment I posted I know for certain that lavender oil is not good for rats in fact it is used for rats propellant. But if you use lavender water to clean the cage it makes a really nice relaxing smell for the lovey rats

Jessica Bamford on April 07, 2020:

I did a quick google search and it appears that the lavender oil is used as a rodent repellent.

Yet there is a study on lavender and calming rats or affecting their serotonin levels, increasing It. You can use lavender spray but I would not use it to them directly

bailyn on March 10, 2020:

my pet rat ate 3-4 soup & oyster crackers, will he be alright? what signs should i look for if something would happen to him?

Mia on March 04, 2020:

i have 4 pet rats, and they love to peel off the skin from blueberrys and eat the inside. they are so cute!!

Amy on February 27, 2020:

Can you give rats lavender water or just lavender in general?

My mum thinks it would help with the smell but I can't find any solid answer whether it is safe or not.

Liliana on February 14, 2020:

Yeah I agree

Erica on February 14, 2020:

Thank you so much for letting me know what to feed my rat

Ninja on January 31, 2020:

Who ever said you are crazy because you like rats i have 2 rats and 11 babies so dont hate on us for loving rats so you dont know that rats are very social and loveing.

Colleen on December 22, 2019:

Our rats love hard boiled eggs and cucumber.

Not saying on October 13, 2019:

I think the page should be specific but not with as much information to what rats can and cant eat. Everything should be in a list with just a word and a sentence or two that gives a bit of information about the food not like 5 sentences because it is a bit too much to read and we dont need that much information. Yes we need information about the words but not that much

Shona on September 17, 2019:

can rats eat salt?

Carmen on August 06, 2019:

This article was very helpful! I'm about to get three pet rats within the next two weeks, and while I've already been told by pet shop employees that they can eat just about anything, this article gave me a much clearer insight on what is safe and unsafe. i greatly appreciate you writing this!

Sarah on August 03, 2019:

Al I know some people don't like rats, I have 2 rats and they are so sweet yeah some rats like street rats are gross and dangerous but pet rats are the sweetest things, You just have to have a special place in your hearts for them, Sorry you don't.

patrick on July 15, 2019:

can rats eat cucumbers?

Al on June 15, 2019:

Anyone who like rats is mentally sick and should be put through electric shock therapy.

Noah Lee Marshall on June 10, 2019:

can rats eat banana peppers???

Grace Kennedy feezell on May 11, 2019:

Why can't pet rats eat dried corn?

Alyssa on March 12, 2019:

I really want to know,please answer this question when you have time and maybe some advise? My rats name is Jacento he is a white rat and i really care about him, i also have a baby rat named shallow, i do all the care for them, my sister isn't interested..

Chloe on December 01, 2018:

Is dairy bad for a pet rat? Can they end up dying?

26snydkath on October 05, 2018:

I love my rats, Colby Jack and Gouda. I let them run in the bathroom because it has tiles, but Gouda got up on the sink and ate a little bit of soap the size of half a pea. Is this okay that he did that? I'll be careful not to let him up there.

Can I give my rats almonds on July 23, 2018:

I have gave them already

Sarah wood on July 21, 2018:

What tipe of Mellon can my rats have

Ginny on May 12, 2018:

I came on this website to see if PLANT FOOD is poisonous in anyway. Because when I let my two pet rats out this morning 1 of my rats; Luna made it up to where my plant pots are- on the windowsill she digested 1 small plant food pellet ball. And I want to know if rats can die from plant food or not, if it helps in anyway possible; Luna is a breed of rat called: Black Hooded Hawthorn.

SARAH on May 03, 2018:

Can rats eat arugula??

carole weir on April 28, 2018:

can rats chew on the cuttlefish shells

Danica on April 25, 2018:

Can rats eat feijoas??

Krystal on April 19, 2018:

i didn't know that rats cant eat certain foots. i just thought that rats eat what ever they want and that they'd be good.

Andrew on March 02, 2018:

My Rats are good rats :) but 2 are very antisocial, and 1 is tired all the time. Is that a problem?

Megen on November 01, 2017:

My rats love apples and bananas

dan on September 25, 2017:

My rat likes to eat bits, doesn't matter what the bits are. Drives me insane:(

Sarah on August 08, 2017:

so can my rats eat bottle brush flowers

licious on July 03, 2017:

my rat just killled my small pet pigeam like a lion hunting for meat

GalaxyRat on April 20, 2017:


You should just decrease the fresh veggies. Maybe feed them only as treats and only leave the blocks for over night.

Jo on April 20, 2017:

We give our pet rats fresh veg and dried pasta each night when we top up they're blocks, change their water. They always have some of their lab blocks still in their dish the next night when we do it all over again, so should we stop giving them fresh stuff each night?

GalaxyRat on April 03, 2017:


Yes, this is extremely normal, because rats eat a lot. My rats eat all their food and usually leave none by the morning. So, your rat is just fine.

alyssa on April 03, 2017:

i feed my rat only rat food but also human food but she eat alot i was told that they should always have food in a bowl for them but my one rat eats all of it in one day and there was like 8 cubes is that normal?

GalaxyRat on April 02, 2017:

Good Hub! I do feed my rats chocolate, but only in small doses.

Emma on March 16, 2017:

Can fancy rats have eggs with salt, black pepper, and ketchup?

Tara A on October 01, 2016:

Thank you for helping me keep my pet rats safe!

Trevin on November 16, 2014:

Ha! I looked over here to see what was poisonous to rats because of franken corn that is supposedly poison to humans because 70% of rats that ate this corn died in their youth. I wanted to see how many things were poisonous to rats and humans to see how bonkers the people who believed this corn is poisonous were. Now I see that this idea of franken corn being human poison is dumb.

(Note to David Dees: You are as crazy about franken corn being human poison as you were when you displayed milk's radioactivity through you're artwork)

dennispowens on October 21, 2013:

Great info on rat diets! Thank you!

MissNikkiSays on October 09, 2013:

Hi there! My pet rats and I enjoyed your page ;-) They would love it if you would stop by and drop them a SquidLike - they are sad because they don't have any SquidFans yet!! Also, just wanted to point out that Kaytee products are not very good for ratties :-( Harlan Teklad 2014 blocks are the best and more nutritionally sound, while Kaytee blocks are full of filler.

anonymous on July 20, 2013:

@anonymous: Not necessarily. I'm a vet and I seriously doubt that anyone would experiment on animals just to find out which foods are toxic to them. There are other ways of knowing, for example by knowing what food wild rats avoid and post mortem exams that can tell which enzymes are or are not present in the liver.

anonymous on January 08, 2013:

@anonymous: I read that link and it sounds as if they are experimenting on rats - something we should be against. They killed so many rats...I don't care if it was humane. They fed them foods that they knew were bad for them...

anonymous on January 08, 2013:

@teamomo: I agree entirely!

anonymous on December 31, 2012:

@teamomo: what if your feeding them kaytee lab blocks? ive been feeding them it as a staple diet plus training and treats and handling time. soy is in the first three ingredients and i think it's a great daily meal for them. what do you think??

anonymous on December 20, 2012:

@VictoriaNeely1: Not only do they love chocolate, I found that when they have to take medicine, hiding it in a teaspoon of chocolate drink (like Boost or Ensure) worked GREAT. It's he same concept as giving meds to dogs hidden in cheese...

anonymous on September 26, 2012:

Thank you so much for this post! It opened my eye to what I'm feeding my rats!Things are changing tomorrow...

teamomo on August 26, 2012:

@Sylvestermouse: but not the best! Don't feed a commercial diet! the healthy diet part isn't so healthy!

teamomo on August 26, 2012:

@VictoriaNeely1: very true!!!

teamomo on August 26, 2012:

Great lens... except one part: What makes a healthy, balanced diet? Not what this page says. Commercial foods like fiesta and kaytee are awful for rats, and contain lots of food in the "not safe" section, like dried corn, and has added unhealthy seeds and peanuts. Don't feed this to rats. Feed them a healthy lab block, like oxbow, and a homemade grain mix of cheerios, total cereal, puffed rice and puffed wheat, oats, dried fruit, uncooked pasta, and sunflower seeds. Also, the portions are all wrong. They should have mostly grain, a few lab blocks, and senior dog food, along with fresh veggies and fruits. Again DO NOT feed a commercial diet!

anonymous on August 17, 2012:

Rats absolutely do not need animal protein (ie meat, dairy, eggs), in the same way that people do not, and it can be detrimental to their health (think saturated fat and cholesterol, why would you feed those to your rat unnecessarily?). If you feed a good quality block such as Harlan Teklad rodent diet or Mazuri Rat & Mouse diet, it contains all the vitamins and minerals they need, and then give them antioxidant-rich fresh fruits and veggies daily, you will be giving them an optimal diet for health.

anonymous on May 16, 2012:

Raw Foods vs. Cooked Foods - The Great American Rat Experiment

I learned a long time ago that commercially prepared pet foods are a bad idea (for many species).

Wedding Mom on May 16, 2012:

Great lens.

Mikana_Rat on April 30, 2012:

What about wild basil and parsley? My rats love to pick some up when going for a walk in the back yard

anonymous on April 03, 2012:

This is a really useful lens and I loved reading it! I never would have thought that about avocados...

JoshK47 on February 10, 2012:

Excellent information here - thank you very much for sharing. Blessed by a SquidAngel!

JessyGene on January 27, 2012:

Great, informative lens!

darciefrench lm on December 31, 2011:

Thank-you very much for this list of what is and isn't safe to feed my rat. He adores being fed human food and I like to give him variety. Now I know what's ok to give him. Many thanks!

VictoriaNeely1 on December 08, 2011:

This is a very comprehensive list. But like others, I have to take issue with chocolate being listed as a poison that causes rats to foam at the mouth and have seizures. Because chocolate is toxic to dogs, people often make the assumption that it must be toxic to rats too--even vets make that mistake and error on the side of caution, since they tend to be very knowleadgeable about dogs and not so well informed when it comes to rats. (Frankly I found my vet's knowledge of rats lacking in other areas too.) But rats are built a little more like us: Chocolate is mostly bad for them for the same reasons it's bad for us. A little chocolate now and then with a balanced diet won't hurt them, and supposedly it can even help soothe respiratory distress. My rats have enjoyed the occasional chocolate treat with no ill effects.

Sources (outside my own experience):

Rats: Complete Care Guide by Debbie Ducommun (who is widely acknowledged as an authority on rats; she was even consulted by Pixar when they were making Ratatouille.)

NorDac LM on November 29, 2011:

Don't have a rat but this was a nicely done lens, very informative.

*** Angel Blessed***

anonymous on May 16, 2011:

I had no idea that rats were sensitive to anything. You will probably save a lot of rats with this. Very well done!

sluggasteve on May 09, 2011:

Never owned a rat..interesting though!

GetSillyProduct on March 28, 2011:

terrific lens, I've had 2 pet rats before and they are very playful and loving if you raise them right. My first pet rat had a thing for pistachios, he would go absolutely mental for them!

Cynthia Sylvestermouse from United States on February 05, 2011:

Wow! What a fabulous resource for a pet rat owner! Great information.

Jayszeman on January 24, 2011:

cool lens. good to know.