Do Guinea Pigs Need Pellets?

Do Guinea Pigs Need Pellets

Nowadays, almost every domesticated guinea pig is fed pellets, partly because of accessibility, but mostly thanks to advertising. People now believe that pellets are a granted part of a guinea pig’s meal. But how much of that is true?

Pellets were created for industrial farming because they’re an easy and cheap alternative to natural foods. In nature, wild guinea pigs (who have the same digestive system as domesticated piggies) would ideally eat grasses, herbs, twigs, leaves, and bark. Obviously, a pet owner can’t provide the small animal with the same diet that it would have in the wild. So, are pellets the necessary alternative?

Do guinea pigs need pellets? The truth is that guinea pigs will not die without pellets. They can’t survive without some of the ingredients in pellets – but they can get all the nutrition that they need elsewhere. Most pellets are alfalfa or timothy hay-based and mixed with multiple ingredients and supplements. Alfalfa is only suitable for pregnant guinea pigs or young ones (under 12 months) because it’s high in calcium and may cause bladder stones in adults. Piggies over 12 months should be fed with Timothy pellets.

There are several types of pellets:

  • Grain pellets (wheat and rye) are very dense and slow down digestion.


  • Gluten-free pellets (quinoa, millet, buckwheat) are better for digestion but not common.


  • Heat-pressed pellets lose their vitamins, so manufacturers add them artificially – at times adding so many that they become harmful rather than beneficial.


  • Cold-pressed pellets retain their vitamins and fibers because they’re not subjected to high temperatures.


  • Fresh/natural pellets are healthiest and are composed of grasses, plants, and herbs. They have a high calcium and water content, and any excess is flushed out in urination.


Certain types of pellets absorb water in the stomach and cause swelling, preventing liquids from reaching the bladder and kidneys and therefore opening the door to complications. These sorts of pellets should only be syringe-fed in small amounts.

Contrarily to hay and grass, pellets aren’t fibrous enough to keep guinea pigs’ teeth trimmed. They satiate so much that the guinea pig doesn’t eat all the fibrous plants and vitamins that it needs. A guinea pig that consumes them should be weighed weekly to ensure that it’s maintaining a healthy weight.

For all the reasons listed above, pellets are only needed as an additive to an already rich diet.

Healthy Guinea Pig Diet

A guinea pig’s diet should consist of high-quality grass hay (orchard grass, timothy hay, oat), a limited amount of pellets, and some fresh vegetables. A guinea pig requires 110 – 220g (1/2 – 1 cup) of leafy greens rich with vitamin C per day, as it cannot synthesize the vitamin and will die of deprivation. Pregnant piggies and babies under 6 months should have an unlimited supply of alfalfa as its high in calcium and proteins, which they need to grow or lactate.

Guinea pigs should not be fed dried fruits, nuts, grains, seeds, cereals, or sugars. High carb diets may cause gastrointestinal problems and obesity.

Guinea pigs depend on routine and habit to feel good. Avoid making any sudden changes in food, feeding times, or containers, otherwise, the piggy might get stressed and refuse to eat. Any changes should be done gradually.

Water bottles with sipper tubes are better than bowls for guinea pigs because they can’t be tipped over or soiled. Still, the piggies tend to chew on the end of the tube or clog it by spitting food into it. Therefore, water containers have to be cleaned and refilled every day. It’s not recommended to add any extra vitamins because many guinea pigs don’t like the taste and may drink less.

Vitamin C

Although pellets are usually formulated with vitamin C, it degrades quickly – pellets should be fed up to 90 days after the production date. Besides that, not all vegetables and vitamin supplements are sufficient. Basically, guinea pigs require vegetables rich in vitamin C in addition to pellets. Otherwise, they may develop scurvy.

Scurvy is a disease caused by vitamin C deficiency. Characterized by blood problems and an inability to create collagen, the illness can be lethal. Collagen is needed to maintain blood vessels, bone formation, and wound healing. Vitamin C deficiency has several effects on the guinea pig:

  • Fragile blood vessels – translates to fragile tissues, especially in the gums, mouth, skin, muscles, and organ surfaces. Some signs are bruising or bleeding of the skin or gums, and a decreased appetite since teeth get loose in their sockets.


  • Wrong bone and cartilage formation – especially around leg and rib joints. Symptoms are swelling, lameness, stiffness, and joint pain.


  • Diarrhea that results in weight loss; rough hair coat; no sexual stimulus; weak and lethargic piggy.


The first step of treating scurvy is to change the guinea pig’s diet (with professional guidance). Lighter cases of the illness can be treated at home. In some cases, piggies require hospitalization. They will receive vitamin C injections, fluid therapy, pain medication, and nutritional support. To avoid unwanted bruising or injuries, limit physical activity for at least the first week of treatment. Gradually allow activities as the piggy’s health improves.

Hay and Grass

An unlimited supply of clean and fresh Alfalfa or Timothy hay is an essential component of a healthy guinea pig’s diet. The small animal chews on it constantly, as its extremely beneficial:

  • Hay helps break down food in the digestive system – protecting the piggy from diarrhea.


  • Hay also keeps their teeth trimmed – guinea pig teeth grow constantly, and without something tough, like hay, to chew on, their teeth will get too big for their mouths. Hard vegetables are a good alternative when trimming.


  • Lastly, guinea pigs like using hay as bedding – then chew on their own mattress at night.


It’s recommended to use a large hayrack rather than spreading hay on the floor of the cage. Guinea pigs often soil themselves and spill water on the ground – which would make the hay soggy and dirty.

A loved, seasonal guinea pig food is fresh grass. It’s rich in vitamin C and nutrients in the spring and summer, but not so much during the rest of the year. A guinea pig should either run in a garden or receive grass pulled out by hand – every day. After one to two hours, any of it should be thrown away. Whoever feeds the piggy should double check that the grass hasn’t been sprayed with herbicides.

Fruits and Vegetables

In order to get enough vitamins and minerals, domesticated guinea pigs should be fed easy-to-digest fruits and vegetables in strict quantities. Piggies generally don’t enjoy change, but they do like to have a varied diet.

Guinea pigs should consume three to five different types of vegetables per day. Fruits have a high sugar content, so they should be given only once or twice a week to avoid fattening the piggy. Many say that a portion should be about the size of a matchbox.

To serve a guinea pig, wash fruits and vegetables thoroughly, dry them, and remove any seeds or pips. Finally, cut them up into bite-sized chunks to avoid choking the piggy.


When it comes to guinea pigs, treats are simply foods that they really enjoy eating. Piggies don’t crave sugary (or any kind) treats like humans do. Honestly, they don’t even enjoy chocolate and cake that much and will probably get sick and fat if they eat them.

Besides fruits, guinea pigs love the occasional fruit tree twig. Once in a while, an owner can even give a piggy a vitamin C tablet as a treat – but only rarely.

Guinea pigs should never consume human food – especially not meat (they’re herbivores) or potatoes. They can’t process pastries, dairy, chocolate, or anything deriving from an animal.

Nuts, seeds, cereals, and crackers aren’t recommended as they can harm the guinea pig’s mouth or cause stomach problems. Guinea pig ‘treat sticks’ shouldn’t be bought either, as they consist mostly of nuts and seeds. The truth is that most store-bought treats are completely unnecessary and even harmful. Any treats that the guinea pig receives should be natural, healthy, enjoyable, and occasional.

In conclusion, pellets are not as necessary as manufacturers make them out to be. There’s no black-and-white answer as the whether they’re needed because it truly depends on the rest of their diet and their general health. Guinea pigs have to consume grass hay (alfalfa or timothy) and vegetables on a daily basis to survive. Fresh, herbicide-free grass is a wonderful meal for the spring and summer. It’s essential to ensure that a guinea pig gets all the vitamin C that it needs per day. Scurvy is a vitamin C deficiency disease, and it extremely unpleasant and possibly lethal.

The occasional fruit is a great treat. Although piggies enjoy them, treats are not a required part of their diet. As long as the guinea pig is fed appropriately and is happy and healthy, owners have nothing to worry about.

Clarissa Moolbrock

Clarissa Moolbrock is one of the founders and editor at Guinea Pig Tube. She is also an author of "Complete Guinea Pig Care Guide: The Essential, Practical Guide To All Aspects of Caring for Your Guinea Pigs" (available on Amazon). Being a veterinary technician helping animals and sharing her experience and knowledge with other guinea pig owners is her passion. Her life goal is to popularise guinea pigs as pets and that is why she has started Guinea Pig Tube website.