Things Not to Feed Your Guinea Pig

Guinea pigs eat a lot. Whenever I think of a guinea pig, I imagine one of them eating or chewing something. No other picture comes to mind. So many owners are negligent to what foods they provide to their guinea pigs, thinking that they can eat anything.

It is true, they CAN eat anything. But that does not mean that you SHOULD let them eat anything. You are responsible for their health, and that is why you should know what not to feed your guinea pigs.

That is exactly why I decided to research this subject and then write this post just for the wellness of all the cute little guinea pigs out there! Below is a list of foods that you should NOT give to your guinea pigs.

Since everyone knows you should not give a live piranha to a herbivorous rodent like guinea pigs, I won’t mention those. But I will elaborate only on the foods that are commonly mistaken to be good choices for guinea pigs.

Foods not to give your guinea pigs:

  1. Meat – of any form!
  2. Dairy items – again, of any form!
  3. Lighter lettuces
  4. Gassy vegetables
  5. Avocado
  6. Onions
  7. Garlic – note: NEVER!
  8. Beans
  9. Plants rich in oxalic acid
  10. Toy parts
  11. Nuts
  12. Chocolates
  13. Tomato leaves and stalks
  14. Seeds
  15. Processed or artificial chemicals
  16. Bananas
  17. Dried Grapes or raisins
  18. Celery

In the upcoming sections, I will write briefly for each of the above mentioned foods why they are not appropriate for guinea pigs. Understanding that will help you understand your pet better, and hence make your relationship much stronger!

1. Meat

Do we really have to explain the grade 3 concepts of herbivores and carnivores over here? Guinea pigs are herbivores and they do not eat any meat. Guinea pigs generally will know it when you give them meat, and will not choose to eat them. But there have been cases where guinea pigs did eat the meat given by their owners.

The gastrointestinal tract of guinea pigs is not designed to digest meat, and giving them meat could result even in death.

2. Dairy Items

Dairy items, whether you agree or not, are artificial when we consider the case of guinea pigs. When you think of what you can feed them, I would suggest that you become a guinea pig in your mind. Imagine it that way. If you are a guinea pig running around in the wild, are you going to find pasteurized milk, cheese, butter or any dairy products? No! So are those the foods that guinea pigs would enjoy? Again, NO!

3. Lighter Lettuces


These types of lettuces, especially iceberg lettuce, give diarrhea to guinea pigs. And that is definitely not something that you wanna gift to your pal!

4. Gassy Vegetables

Cabbages and cauliflowers are vegetables that are bloaty and hence will create gas. We have mechanisms in our gastrointestinal tract to process and overcome excess gas. But guinea pigs do not have any such mechanisms.

5. Avocado

A huge glass of pure avocado juice may sound tempting to you. It may make a great drink for your workout and cycling. But remember, you are now a guinea pig (for time being)! Avocados are too much fat and carbohydrates for guinea pigs to process. So do not clog their mechanism with avocados.

6. Onions


Onions are filled with disulfide. Disulfide, even for humans, is quite dangerous. This is because of its tendency to damage the red blood cells that are in the bloodstream. When the number of red blood cells decreases, oxygen does not reach all parts of the body in necessary amounts. And when that happens, the guinea pig gets anemic and leads to weakness, breathing issues, and even death in severe cases.

7. Garlic

Let me get this straight into your head because it is important, garlic is pure poison for guinea pigs! Or any bulbs for that matter, they are all poisonous for guinea pigs.

Garlic is rich in calcium and phosphorous. These are the two minerals essential for healthy bone density and strength. But this being the only benefit, the problems caused by it are much bigger.

Garlic may be great for us and our bones. But in the case of guinea pigs, they are not able to process large amounts of calcium and phosphorous. When present in excess amounts, they will get deposited in the kidneys or bladder in the form of stones. That obviously is not good news. Stones like that make urination itchy, stinging and painful. When left unchecked, kidney stones could even lead to kidney failure which would ultimately lead to death.

8. Beans and Potatoes

Again, these two lead to excess gas in the stomach of guinea pigs. I already told you about how guinea pigs cannot get rid of excess gas that builds in their gastrointestinal tract. So avoid beans and potatoes too.

9. Plants Rich in Oxalic Acid


One such plant is rhubarb. These plants rich in oxalic acid lead to failures in the excretory system. Oxalic acid is way too complex to be broken down by the simple mechanisms in the body of guinea pigs. Some of the complications include kidney stones, kidney failure, blood in the urine, or even death in severe cases.

10. Toy Parts

I say this to all my friends enquiring about getting a guinea pig: “Consider your guinea pig more as your child than as your pet”. So imagine you have a kid, will you give the toddler lego blocks to play with? You won’t unless you are a very very irresponsible parent!

So my point is, do not give your guinea pigs the toys which have parts that they can swallow. Whenever you choose a toy for your pal to play with, make sure that you do not give them any toys from which little parts can be chewed out as bits. Such bits are sharp, never digestible in any natural digestive system, so they do not belong even in the habitat of your pet!

11. Nuts

Nuts are great. They are nutritious, they are nice to bite, they are delicious, they are just awesome! Oh sorry, I just switched to the human mind for a moment there. So switching back to the guinea pig mind, thinking of nuts, I would feel like throwing up!

They are just too much fat and carbohydrates for a guinea pig to process in its digestive system. So do not give them the burden of digesting nuts through hours when they can have a light treat and then move on with playing around.

Many owners are finding that guinea pigs are enjoying peanuts. The opinions on feeding guinea pigs with peanuts are mixed. My suggestion based on what I observed is that peanuts are not great choices too.

12. Chocolates


Again, I am no expert in chocolates and I have no idea how they are made. But I do eat them a lot, and I am pretty sure chocolates are made from milk and its products. I do know that it is a lot of sweet with a lot of carbohydrates. I do know that they contain cocoa which is rich in minerals like calcium and phosphorous. And I guess I have covered why all of those are bad for guinea pigs.

So, chocolates, never to be on the list of treats to buy for your guinea pigs!

13. Tomato Leaves and Stalks

Tomato leaves and stalks are made of complex substances including several carbohydrates and even cellulose, tomatine, solanine, and other alkaloids. Even we humans with all the very well developed digestive system are incapable of breaking these substances down to simpler molecules. So I guess there is no need to say that guinea pigs cannot, it is obviously understood!

Although, tomatoes are surely among the most-enjoyed treats when it comes to guinea pigs. The only thing to decide is whether it is to-mae-toes or to- maah-toes. Oh, wait, also to decide is whether tomatoes are fruits or vegetables!

14. Seeds

Seeds make the worst choice of food for guinea pigs. These are bad because of so many reasons. A seed is a plant’s reproductive mechanism, and seeds are to stay dormant yet alive for even months or years before they get favorable conditions for germination. So they are enriched with a loooooot of fat and nutrients in them for their dormant period.

Not just that, seeds are tiny. Ingesting seeds could lead to choking in guinea pigs. And that is definitely not good!

Some even contain substances that are toxic to guinea pigs.

One very IMPORTANT thing to note is that apple seeds are NOT good for guinea pigs! So you have to be very careful while giving apples to your guinea pigs, make sure you remove the seeds first. This is essential because apple seeds contain arsenic and it causes several complications in the bloodstream, excretory system, and the digestive system.

15. Processed or Artificial Chemicals

Anything that does not qualify as a food for humans surely does not qualify as food for guinea pigs. Although, the converse is not true.

When you provide toys for your guinea pigs, make sure it is not coated with varnish, paint, dyes or glues. Even though this does not come in the list of foods to avoid, it does come in the list of items that are not supposed to be eaten by guinea pigs.

16. Bananas


If you ask me if guinea pigs can eat bananas, I would say yes they CAN. But remember, that does not mean that they SHOULD. Banana is great. It is nutritious. It is healthy. But only as long as it remains a “treat”. It should never become your guinea pig’s food or as a regular meal. Feeding them with bananas maybe once in a week is fine. This is because they are high in sugar content.

There are several precautions to take when feeding your guinea pigs with bananas. And bananas are very abundantly available, making them a common food that owners choose for feeding guinea pigs. That is exactly why I am going to elaborate well in detail on why banana should not be a part of the everyday diet for your guinea pigs.

Things to Note When Feeding Bananas to Guinea Pigs

  • Feed only fresh and ripe bananas
  • Avoid processed banana chips
  • Feed only in small quantities
  • Only once in a week, you should give your guinea pigs bananas.
  • Do not completely avoid giving bananas because they are essential too. They provide more than enough vitamin C which is essential to prevent scurvy- a disease caused by vitamin C deficiency. When a guinea pig is affected by the scurvy disease, effects could include skin and bone health issues, weight loss and even death in severe cases. Vitamin C is an essential supplement because they cannot be produced naturally in their bodies, and has to be obtained from the diet.
  • If you can afford vitamin C supplements in pellets, buy them from the pet stores. But if you can’t, you can feed your guinea pigs with bananas. But I should warn you, bananas should not be the sole source of vitamin C.
  • Banana peels are better than banana itself when it comes to nutritive values. Bananas have fiber, sugar, and a lot of calories. But peels have fiber, a little less sugar, and a lot of antioxidants. Studies have revealed that an unripe banana peel is very rich in antioxidants. So consider feeding your guinea pig with them once in a while. You may ask why antioxidants are important. It is quite simple. They help in getting rid of molecules that cause blood circulation issues and cancer. Apart from antioxidants, banana peels also are rich in vitamin B, potassium and magnesium. Magnesium is the most important supplement for proper metabolism. Potassium is essential for the nervous system and muscle movement. And on top of all that, the fiber and protein help in healthy growth.
  • Yeah, banana peels are great. But still, too much of anything is good for nothing. They are still rich in sugar. Below is a section dedicated to explaining why too much sugar is not good for guinea pigs. So feed banana peels too in limits. Once in a week is appropriate enough.

Ill Effects of Excess Sugar in Diet

  • Diarrhea
  • Diabetes: Guinea pigs are prone to both types of diabetes- mellitus, and insipidus. But unlike humans, remission from diabetes is possible in case of guinea pigs. If you can regulate their diet, control the sugar intake and bring down the weight, your guinea pigs can achieve remission from diabetes.
  • Loose stools
  • Mood swings
  • Obesity

17. Raisins

Grapes are not bad for guinea pigs. But dried grapes, are not supposed to be part of an everyday diet. The process by which grapes are dried into raisins will concentrate the sugar. This leads to a 72% sugar content by weight in dry grapes.

It is suggested that you give fresh grapes to your guinea pigs 4 times a week in little portions. But raisins, only once in a month is recommended. And even then, not more than two or three raisins.

I already told you about how sugar is not good for guinea pigs. Raisins are especially bad because they are like chocolates are for humans. They are nice to eat, but too much together would lead to negative feedback from the body mechanisms.

Raisins are tiny, and they are highly concentrated with complex sugars. They could get choked on the food pipe of guinea pigs on top of the negative effects it causes because of the sugar.

18. Celery

Celery is a great choice of food for guinea pigs. But again, like bananas, celery cannot be consumed beyond limits. You can feed your guinea pigs with celery once in 3 days, in small quantities.

The leaves of celery plant are more nutritional than the stalks, and hence I suggest giving celery leave to your furry playmates. Although, if you live in the urban regions and you can’t find celery with leaves in the big supermarkets, feeding them the stalk is the next best thing you could do.

Many people feed celery every day to guinea pigs, and then complain about the loss of appetite, loose stools and signs of depression.

Another common mistake when it comes to feeding guinea pigs with celery is that some owners think the stalk or the more stringy parts are not desirable. That is not true. Those are the parts that are better because they are not too soft for the sharp teeth of guinea pigs like leaves are. They are neither too soft, nor too sturdy, making them perfect for chewing on.

One most important thing to note while feeding guinea pigs with celery stalks, is the quantity. Experts suggest that you do not give exclusively the celery stalk alone. A mixed salad with many leafy vegetables that has only a little piece of celery stalk, is good enough. One-sixth of a whole celery stalk is considered more than enough.

Please be careful and look into poisonous or toxic foods to avoid in this article we wrote for the health and safety of your guinea pig.


My name is Anna and I work full time in my local pet shop where we sell many animals that I write about on this site. I love all animals and love writing about them.