Foods That Are Poisonous to Your Rat

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 what foods are safe, what foods should be fed only once in a while, and what foods are poisonous to pet rats?

Below, you'll find answers!

Fact or Fiction?

"Pet rats instinctively know what to eat and what to avoid."

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
    Rat's 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 you 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.

  • Beans: Raw or Dried
    Share well-cooked beans with your rat but never uncooked or dry beans which contain hemaglutin, 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.
  • 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!

Serve These Foods Cooked, Not Raw

  • Artichokes
  • Beans
  • Brussels Sprouts
  • Corn
  • Egg
  • Red Cabbage
  • Sweet Potato
  • Meat

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 has 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 in 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 Maerica: Can I Make My Own Rat/Mouse Diet?

Rat & Mouse Club of America: Chocolate and Rats

Rat Care Guide: Diet

Readers' Thoughts and Comments 29 comments

Loverats 13 days ago

I fedon't my rate grapes he loved it

Tara A 2 weeks ago

Thank you for helping me keep my pet rats safe!

Trevin 23 months ago

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 profile image

dennispowens 3 years ago

Great info on rat diets! Thank you!

MissNikkiSays profile image

MissNikkiSays 3 years ago

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 3 years ago

@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 3 years ago

@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 3 years ago

@teamomo: I agree entirely!

anonymous 3 years ago

@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 3 years ago

@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 4 years ago

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

teamomo 4 years ago

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

teamomo 4 years ago

@VictoriaNeely1: very true!!!

teamomo 4 years ago

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 4 years ago

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 4 years ago

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 profile image

Wedding Mom 4 years ago

Great lens.

Mikana_Rat 4 years ago

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

anonymous 4 years ago

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

JoshK47 4 years ago

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

JessyGene profile image

JessyGene 4 years ago

Great, informative lens!

darciefrench lm profile image

darciefrench lm 4 years ago

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 profile image

VictoriaNeely1 4 years ago

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 profile image

NorDac LM 4 years ago

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

*** Angel Blessed***

anonymous 5 years ago

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

sluggasteve 5 years ago

Never owned a rat..interesting though!

GetSillyProduct 5 years ago

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!

Sylvestermouse profile image

Sylvestermouse 5 years ago from United States

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

Jayszeman profile image

Jayszeman 5 years ago

cool lens. good to know.

    Sign in or sign up and post using a HubPages Network account.

    0 of 8192 characters used
    Post Comment

    No HTML is allowed in comments, but URLs will be hyperlinked. Comments are not for promoting your articles or other sites.

    Click to Rate This Article