What Do Guinea Pigs Eat

This is always something good to know before jumping into owning a new pet. It is something that I didn’t fully know myself when getting our first guinea pig. You just may be surprised at some of what I have learned and am now passing on to you 

What Do Guinea Pigs Eat?

The main part of a Guinea pig’s diet is hay. They are herbivores, and so they will eat a diet of many plant-based foods. There are also pellets that are enriched with vitamin C that is necessary for them. Add in some fresh fruits and vegetables and you will have all you need to feed your guinea pigs.

However, hay should always be available to them. This is a top priority that I will explain further down in this post. And they need the added vitamin C these 2 points play a vital part in your guinea pigs health. 


Hay plays a vital role in keeping the guinea pig’s digestive system working. It is also necessary for them to continually chew on hay to keep their teeth worn down properly. If your guinea pig doesn’t keep their teeth worn down they can develop dental problems that can ultimately lead to them starving to death.

You can mix the hays like Timothy, oat, and orchard. Adding a little alfalfa hay now and then just as a change might be nice. However, alfalfa hay is higher in calcium so shouldn’t be the daily main hay, use as a supplement along with other hays as a treat.


About ⅓ cup of good vitamin C enriched pellets specifically for guinea pigs should be offered 1 a day. Guinea pigs can’t produce vitamin C for themselves and are therefore susceptible to scurvy. So a diet high in vitamin C is recommended. 

Fresh Foods

You should give about 1 cup per guinea pig of fresh vegetables, with a little added fruits each day.  Green and red leaf lettuces, parsley, silverbeet, and kale should be a good part of the fresh vegetables you provide. Think about vegetables with high levels of vitamin C in them as red or green pepper and broccoli.

Give them a mixture and switch things around daily to give them a variety.  Add to the greens things like carrots, tomato, banana slice, apple slice, sweet potato, zucchini, or blueberries once or twice a week. 

How Much Should A Guinea Pig Eat?

Your guinea pig should munch on hay all throughout the day. This is vital to their digestive system. A guinea pig can develop digestive problems if it goes without eating for just a few hours. For this reason, always keep hay available for them.

You will need to provide about ⅓ cup of pellets that are enriched with vitamin C once a day. Be sure to check and make sure that your guinea pig has contaminated this by kicking bedding and poop into this dish.

Your guinea pig will need 1 cup of fresh vegetables and fruits. You can do this all at one time, but I spread it out and offer it fresh food a few times during the day so there is less chance of it becoming inedible and spread throughout the cage. Always remove all uneaten fresh foods within 24 hours if it is uneaten.

As important as it may be to know what to feed your guinea pig and how much they need to eat. It is equally important to know what they can not eat. As some things can be very detrimental to the health of your guinea pig. And while a few may have done so before with no problems isn’t an excuse to take that risk.

When Should A Guinea Pig Eat?

A guinea pig will seem to always be eating. This is necessary, you must always have hay available for them. The pellets and the fresh food can be given whenever it is most convenient for you. They are up and down through the night so feeding them in the morning and in the evening seems to work really well.

It isn’t as important for you to feed them at a given time as it is for you to stay relatively consistent on when you do it. It is also important for you to keep the older food cleaned up before they go bad and get moldy.

What Should A Guinea Pig Not Eat?

Guinea pigs can develop calcium stones in their bladder so try avoiding items high in this ingredient. Strawberries, parsley, spinach, and celery are high in oxalates and should be avoided if your guinea pig starts to develop bladder stones.

Some foods can in fact cause significant health issues. Make sure you do not feed your guinea pigs the following foods, cereals, nuts, or seeds. Dried beans, corn, peas, avocado, onions, potatoes, mushrooms, rhubarb, dairy products, and chocolate. And no meat-based products.

You will want to avoid the following foods that can be gaseous like beans, cabbage, and cauliflower, they can cause bloat as a guinea pig has no way to dispel the gas. Avoid all bulb plants like onions, chives, shallots, and garlic. 

This list in no way gives everything that a guinea pig should not eat. It however lets you know there are many things they can not eat and will make you question something before offering it. When in doubt never offer anything without consulting with your vet.

How Much Should A Guinea Pig Drink?

This will vary greatly for many reasons. It seems they need approximately 20% of their body weight in water each day or roughly 3 oz. This will vary depending on Pig, weather, and other environmental factors like humidity. 

This doesn’t mean, however, that they will sit at the bowl or bottle and drink that amount. So if you are watching to see how much they drink you may be going crazy thinking there is something wrong. If they are eating vegetables high in water this will take the place of getting a drink.

A guinea pig can get enough water from their food to not have to drink any other water. They should always have fresh water changed daily available. It is less important for them to drink water than it is for you to know what is normal for your guinea pig and to monitor that all is well.

If there is a sudden change in the eating and drinking habits of your guinea pig you will want to consult with your veterinarian. These changes may indicate there is a medical problem that needs to be addressed.


Guinea pigs need to have Hay available at all times. This is essential for both digestive and dental health. They need to have pellets that are specific to guinea pigs, as these are formulated with vitamin C and other nutrients need by guinea pigs. 

There is a wide variety of fresh foods that your guinea pig can eat. Shifting these around will keep the diet more interesting. It is up to you and your guinea pig when to feed them what. Workaround your schedule, and make sure fresh stuff isn’t sitting to long.  

There are also many things that are toxic to guinea pigs. So be careful to know what they are getting and have all the information before deciding to give them something. 

Water consumption varies and can actually be gotten in their food. If you are concerned always turn to your vet for the best answers.

Rick Matthews

Hello, I am Rick Matthews, I have helped raise 100's of pets in my life living with my Father who while we did not live on a farm, raised all sorts of animals to sell them to families. We had so many different pets we all quickly became experts intending to them and helping them stay healthy. Back then we did not have the internet to look up thing on how to take care of their kids. As my kids got older, they wanted pets and of course, I did not want to have as many as we did when I was a child, but wanted to share my experiences. Many of these articles are written to help educate families on what to expect when looking to get a new pet for their children.

Recent Posts