Your chosen guinea pig diet is essential to ensure your pet remains happy and healthy. As a loving pet owner, it’s important to understand the dietary needs of your guinea pig, which is essential for their health and longevity. These small, fluffy herbivores have specific nutritional requirements, with guinea pig hay as the cornerstone of their diet. This comprehensive guide will cover everything you need to know about feeding your furry friend properly.
What Makes Up a Balanced Guinea Pig Diet?

Several key components make up a nutritionally complete diet for guinea pigs. The ideal diet should be based on unlimited high-quality guinea pig hay supplemented with fresh vegetables, limited fruits, small pellets, and access to plenty of fresh water.
Guinea pigs will do best on a diet high in fibre, moderate in vitamin C, low in fat, and low in calcium. Unlike many mammals, guinea pigs can’t make their vitamin C, so this is a nutrient you’ll need to ensure is provided in their diet. Guinea pigs can develop scurvy if they don’t get enough vitamin C, which leads to painful joints, slow wound healing, and dental issues.
Why is Hay So Important for Guinea Pigs?

Guinea pig hay is essential to your pet’s health and should make up about 80% of their daily intake. Hay provides essential fibre that keeps your guinea pig’s digestive system functioning properly and helps prevent dangerous intestinal blockages.
Another benefit of chewing hay is that it helps wear down your pet’s constantly growing teeth, preventing dental problems that can become a serious health concern. There are various types of hay available for guinea pigs:
- Timothy Hay: This is the gold standard for adult guinea pigs. It’s high in fibre and low in calcium and protein.
- Orchard hay: A good alternative to Timothy, but softer in texture.
- Meadow hay: Contains a variety of grasses and plants, offering different flavours.
- Alfalfa hay: This type of hay is higher in calcium and protein and suitable only for pregnant, nursing, or very young guinea pigs (under 6 months of age).
To keep your guinea pig in optimal health, always ensure it has constant access to fresh, clean hay. Providing a hay rack that keeps the hay off the cage floor is a good idea, as it prevents contamination and reduces waste.
How Much Fresh Produce Should Guinea Pigs Eat?

Fresh veggies should comprise 10-15% of your guinea pig’s diet. Aim to offer your guinea pig one cup of mixed vegetables per adult daily. Bell peppers are a great option, as they pack a vitamin C punch that is essential for guinea pig health. Leafy greens are an excellent choice, but not all are created equal.
Other vegetables that make excellent additions to your guinea pig food rotation include:
- Romaine lettuce (iceberg lettuce is less optimal as it offers little nutritional value)
- Cucumber
- Carrots and carrot tops (less frequently due to the sugar content)
- Zucchini
- Tomatoes (not the leaves)
- Kale (moderately, as it’s high in calcium)
- Broccoli (in moderation to avoid gas)
Introduce new vegetables gradually to avoid digestive upset. A variety of vegetables ensures your guinea pig gets a range of nutrients and keeps mealtimes interesting.
What About Commercial Guinea Pig Pellets?

Good quality guinea pig food pellets should comprise only about 5% of your pet’s diet. This amounts to around 1/8 cup per day for an adult guinea pig. Look for plain Timothy hay-based pellets specifically formulated for guinea pigs that contain added vitamin C.
Meusli-style guinea pig food mixes that contain seeds, nuts, dried fruits, and coloured pieces should be avoided as they encourage selective eating, where your pet might only eat the bits that they find the tastiest (and often the least nutritious). In addition, seeds and nuts can be too high in fat, leading to weight gain.
It’s important to note that vitamin C degrades over time, so that pellets will lose their nutritional value after about 90 days from manufacture. Always check the production date and purchase only what your pet will consume within three months.
Can Guinea Pigs Eat Fruit?

While fruits can be given to guinea pigs, they should be given sparingly due to their high sugar content. Limit fruit to an occasional treat, no more than 1-2 small pieces a few times a week.
Good fruit options include:
- Small pieces of apple without seeds
- Strawberries
- Blueberries
- Small sections of orange
- Small pieces of pear
While fruits contain vitamin C, your guinea pig’s main source of this essential nutrient should be their pellets or vegetables.
What Foods Are Toxic to Guinea Pigs?

Knowing what not to feed your guinea pig is just as important as knowing what to feed them. Some foods can cause serious health issues or even be fatal to these sensitive creatures.
Never feed your guinea pig:
- Chocolate and caffeine
- Onions, garlic, and leeks
- Dairy products
- Meat or animal products
- Bread or other baked goods
- Potatoes
- Rhubarb
- Mushrooms
- Avocado
- Seeds and nuts
- Processed human foods
- Other pet food, like dog food
If you’re unsure about a food item, it’s best to err on the side of caution and not offer it to your pet.
How Do I Transition My Guinea Pig to a New Diet?

Sudden changes in guinea pig food can cause digestive upset, potentially leading to dangerous conditions like GI stasis. If you need to change your guinea pig’s diet – switching to new hay or introducing new pellets – do so gradually over 2-3 weeks.
Mix a small amount of the new hay or pellets with the familiar food. Gradually increase the proportion of new food while slowly decreasing the old. This will allow your pet’s digestive system time to adjust to the new guinea pig food.
How Can I Tell If My Guinea Pig Is Getting Good Nutrition?

A well-nourished guinea pig will have bright eyes, a glossy coat, and maintain a healthy weight. They’ve been active and alert, with consistent eating habits and normal droppings. Regular weighing can help you keep track of your guinea pig’s weight. A sudden weight change can indicate a potential issue.
Signs of nutritional deficiencies, particularly vitamin C deficiency, may present as a rough coat, swollen joints, lethargy, or dental problems. If you notice any concerning changes in your guinea pig’s appearance or behaviour, consult a veterinarian specialising in exotic pets.
Conclusion

Providing your guinea pig with a balanced diet centred around high-quality pig hay, fresh veggies, minimal pellets, and the occasional fruit treat will ensure your pet lives a healthy and happy life. Proper nutrition is the foundation of good health, and understanding your guinea pig’s specific dietary needs will ensure you’re being the best caretaker for your furry friend.