Can You Overfeed Guinea Pigs?

The question of diet is essential to every pet owner—what should your pet be eating and not eating? 

When it comes to guinea pigs, the question of “how much” is especially important. 

We’re here to answer your questions about whether or not it’s possible to overfeed your guinea pig.  

It is possible to overfeed guinea pigs since they can eat even when they’re full. Overfeeding is an issue, as it can lead to digestive problems and obesity. Hay and water should be provided in a steady supply, but keep an eye on how many pellets, vegetables, and fruits you add to the mix.

Read on to find out more important information about guinea pig food, including the proper balance of types and amounts you should be feeding your pet. 

You won’t want to miss these helpful dietary tips! 

Guinea Pig Feeding And Overfeeding: The Basics

While overfeeding guinea pigs is possible, it’s not so simple as just the amount you’re providing. 

Certain kinds of foods are presented in a larger quantity, while others should be more limited. 

For example, guineas should always have some amount of hay available in their enclosure—their recommended daily diet consists of 80-85% hay. 

Another 10-15% should be fresh vegetables, while the remaining 5% or so should be guinea pig pellets.  

Guinea pigs naturally consume food at a high frequency, so it’s okay if your pet seems to want to eat it all the time. 

You just need to be sure the food you’re providing is healthy and in the correct ratios. 

As with humans, guinea pigs need specific vitamins from their food, like Vitamin C. 

If they eat too many sugary treats or food without the proper nutrition—or just too much food in general—they can develop health issues and become obese, just like humans. 

Let’s take a closer look at the recommended guinea pig diet and feeding schedule to help you avoid these issues.

What Can Guinea Pigs Eat? 

First and foremost, hay is the staple of a guinea pig diet. 

Hay provides fiber essential to the digestive process, which is why it’s key your guinea has access to this food item at all times. 

Guinea pig teeth also grow constantly, and chewing hay helps to keep their teeth in check. 

High-quality timothy hay is an excellent choice for an adult guinea pig. 

Alfalfa hay works well for a baby guinea pig or pregnant guinea pig since it’s high in calories, calcium, and protein, which a growing guinea needs. 

Pellets, a commercial food, are also an essential part of your pet’s diet, though a much smaller one. 

Pellets are engineered to provide balanced levels of vitamin C and other key nutrients but should be viewed more as a supplement. 

1/8 cup of pellets per day is plenty. 

Fresh vegetables (and herbs) are another major component of the guinea pig diet. 

Serve a variety of veggies to your pig, but be sure to introduce new ones individually and see how they react. 

One cup of vegetables per day for a guinea is a good amount. 

Both leafy greens and non-leafy vegetables are safe for guinea pigs. 

Top choices include:

• Romaine lettuce
• Carrots (and carrot tops)
• Green and red bell peppers
• Cilantro
• Parsley
• Kale
• Spinach
• Tomatoes 

These critters also love fresh fruit, which can make for an occasional perfect treat (you’ll want to avoid excess fruit because of the high sugar content). 

Fruits act as a solid alternative to commercial treats since they contain more vitamins than the processed stuff.  

Some fruits to reward your pet in small bits (and not every day) include:

• Apples
• Strawberries
• Blueberries
• Pears
• Oranges
• Kiwi
• Peaches

What Can’t Guinea Pigs Eat?

After going over what works, you may be wondering if there are certain foods guinea pigs should not eat. 

It’s true there are certain items which may be bad for your pet, whether because they are poisonous, a choking hazard, or simply lack the necessary vitamins. 

As a rule of thumb, here is a short list of foods to avoid giving your guinea:

• Chocolate
• Bread
• Meat
• Peanut butter
• Dairy products
• Spicy food
• Nuts
• Avocado
• Iceberg lettuce
• Mushrooms
• Onions
• Garlic
• Potatoes

Be sure what you do provide is fresh food, too. 

Keep the cage clean and switch out stale pellets and hay every 24 hours. 

Don’t let uneaten food build up for sanitary reasons and because they will also lose interest in the food if it’s too old. 

Never feed your guinea cooked food, either.  

Always opt for natural food over commercial or processed options, which can contain chemicals and make your guinea pig fat.

If your pet is fat, check out our post on how to help guinea pigs lose weight.

Don’t serve plants or flowers from your house or garden, as they may contain pesticides or be toxic. 

This point is essential to note if you let your pet roam outside, as you should supervise the kinds of plants they’re exposed to in each new environment. 

We have a great post listing all the different foods people wonder if guinea pigs can eat or not if you’d like an exhaustive food list.

Are There Certain Vegetables To Avoid Overfeeding?

While vegetables are an advisable and necessary part of a guinea pig’s diet, there are certain vegetables you should only serve in moderation. 

Based on the nutritional makeup of a particular vegetable, some will be better than others.

For example, carrots are a bit on the sugary side, so don’t overdo it in this department. Broccoli is high in oxalates, which bind with calcium. 

Too many oxalates and your guinea can develop bladder stones.  

Leafy green vegetables like romaine lettuce, along with the parsley and cilantro herbs, should safely make up the bulk of the veggies you provide.

Even within leafy greens, darker greens (like spinach and kale) will have more nutritional value and should be favored. 

You can read more about feeding guinea pigs spinach in our other post.

Iceberg lettuce contains lactucarium, a substance harmful to guinea pigs.  

Red and green pepper, tomatoes, and other options high in vitamin C should also be fed regularly (30-50mg daily), as guineas can develop scurvy without it. 

If your guinea pig develops loose stool, reduce the number of fresh vegetables you’re serving and slowly reintroduce them in smaller portions, one by one. 

If a particular veggie disagrees with your pet, you may need to do some experimenting. 

How Often Should You Feed A Guinea Pig?

Feed your guinea pig on a regular schedule of twice a day, morning and evening. 

If you feed them throughout the day without a routine, you’ll be more likely to overfeed them and lose track of how much they’ve consumed. 

Always ensure there is fresh hay in their cage throughout each 24 hour period. 

Change out any old hay, pellets, or vegetables still untouched after 24 hours.  

Read our post on how often to change out guinea pig hay for more information.

Your piglet should also always have access to freshwater. 

Keep a supply of clean water in an automatic water dispenser hung on the bars of their cage, and remember to refresh it every 24-48 hours as well.

Provide a fresh meal once in the morning and once in the evening, keeping the total amount of vegetables to about a cup or so in total each day. 

Remember to keep fruit to a minimum. 

Split up the amount of fresh food between feedings. 

As mentioned previously, the total amount of pellets fed in the course of one day should amount to about 1/8 cup. 

When in doubt, if your guinea pig still seems hungry after eating the allotted amount of fresh food and pellets, satisfy them with additional hay rather than supplementing further with veggies, fruits, or pellets. 

And what about going without food?

We have an excellent post on how long guinea pigs can go without food and water that’s good to learn about in case something happens.

What Happens If You Overfeed A Guinea Pig?

Common issues arising if your guinea is eating too much include:

Tooth decay: caused by overeating high-sugar items.

Obesity: caused by simply eating too many calories.

Urinary tract problems: can develop if your pet is ingesting too much calcium. Bladder sludge (cloudy urine) is a sign of a urinary infection.

Heart problems: from congestive heart failure to atherosclerosis (a blood vessel disease).

Imbalance of gut bacteria: too much sugar can throw off the proper balance of bacteria in the digestive system.

Gastrointestinal stasis: meaning water and food cannot pass through the digestive system at a regular rate.

Follow the above protocols to prevent your guinea from developing any of these digestive issues. 

Consult a vet if your guinea appears ill. 

Exercise is another key factor in combating obesity, in particular, so also ensure your pet has plenty of cage floor space. 

Consider adding boxes and tunnels to their play space to encourage them to stay active. 

Can A Guinea Pig Die From Overeating?

These creatures, while having a seemingly insatiable appetite, are unlikely to die from overeating alone—it’s not as if the eating itself will be the death of them.

The real concern is the effects overeating can have on their health (see above). 

If any of these digestive issues or level of obesity gets out of hand, the conditions are life-threatening.  

How Much Should A Guinea Pig Weigh?

A fully grown guinea pig female should weigh between 700 and 900 grams, while the average adult male should weigh in around 900 to 1200 grams. 

Weigh your pig at least once a month, if not more. 

Any spikes in weight, either up or down, can indicate health issues. 

If they are overweight, cut down on the amount of food you’re providing, starting with pellets, treats, fruit, and other more sugary items.

Use a regular kitchen or bathroom scale to weigh them in, so long as it fits their entire body.

Alternatively, weigh yourself first. 

Then grab the guinea pig and weigh yourself holding it. 

Subtract your original weight to get the pig’s weight. 

Why Are Guinea Pigs Always Hungry? 

While all this information is well and good, why exactly do guinea pigs eat so much in the first place? 

Why the need to monitor this behavior in a domestic guinea pig? 

This species forages naturally—guineas are grazers and need a steady supply of food to continue operating at full capacity. 

It’s instinctual!

If your pet seems to be eating even more than normal, though, there could be a few reasons why:

Shedding: molting or shedding their coat in the spring takes a lot of energy, so they’ll require more food at this point.

Breeding: pregnancy is also very demanding on the body, so the appetite of a female guinea often increases at this time (though this will only affect your pet if she’s undergone mating with a male!).

Parasites: a parasite can take the nutrients from a guinea pig’s intestinal system, leading to a spike in their appetite.

Diabetes: though uncommon in guinea pigs, an increase in appetite followed by weight loss is a sign of diabetes and will require diet changes.

Guinea pigs should often be eating, as it is the natural behavior of their wild counterparts. 

Yet you should be sure they are eating the right things for the right reasons. 

While you may supply a pretty much unlimited quantity of hay (whenever their cage is empty of it) for them to graze at their leisure, they shouldn’t overindulge in sugary foods like fruits or even fresh vegetables.

It’s also worth considering whether guinea pigs stop eating when they are full.

In the wild, fresh vegetables may be harder to come by, so they will eat and eat in preparation for a long spell without them. 

However, domestic guineas are closer to their next veggie than they may think. 

What If My Guinea Pig Isn’t Eating Enough?

If, on the other hand, your pig isn’t eating enough, this is also a severe issue. 

Signs of a problem include: 

• Weight Loss
• Loss Of Appetite 
• Depression 
• Rough Hair
• Loss Of Elasticity In The Skin 
• General Lethargy 

This decrease in appetite or refusal to eat at all could be traced to: 

• Stress
• Environmental Changes
• Dietary Changes
• A Recent Medical Procedure
• Extreme Temperatures
• Not Enough Fresh Water
• Infections 
• Dental Problem

If you are providing the proper diet and amounts of food and your guinea is still not eating, you should consult your vet to get to the bottom of it. 

Your guinea pig needs a new or adjusted environment, or they could require special dietary supplements.  

If your guinea pig doesn’t eat for as much as 12-24 hours, it could become dangerous to their health and should be treated as an urgent matter.