How to Feed a Guinea Pig Properly

Introduction

Feeding a guinea pig properly is more involved than most new owners expect. Guinea pigs have specific nutritional requirements — most notably, they cannot produce their own vitamin C and must get it from their diet every day. Here's a complete guide on how to feed a guinea pig correctly.

The Three Pillars of Guinea Pig Nutrition

1. Unlimited Hay — The Most Important Food

Hay should make up approximately 80% of a guinea pig's diet and must be available 24 hours a day. It provides the long-strand fiber essential for digestive health and helps wear down continuously growing teeth. Oxbow Orchard Grass Hay is an excellent everyday choice — soft, fragrant, and highly palatable. Kaytee Timothy Hay Blend Cubes can be offered as an enriching alternative. Use a hay feeder rack to keep hay fresh and accessible.

2. Fresh Vegetables — Daily Vitamin C Source

Fresh vegetables are essential for guinea pigs, primarily as a source of vitamin C. Offer 1–2 cups of fresh leafy greens per guinea pig per day. The best options include:

• Bell pepper (any color) — the highest natural vitamin C content of any common vegetable; offer daily
• Romaine lettuce — hydrating and nutritious; excellent daily staple
• Cilantro — most guinea pigs love it; good vitamin C source
• Parsley — high in vitamin C and K; offer in moderation due to calcium
• Kale — nutritious but high in calcium; limit to 2–3 times per week
• Cucumber — hydrating; great in summer
• Zucchini — mild and easy to digest

3. Pellets — Concentrated Nutrition

High-quality pellets provide vitamins and minerals that may be lacking in hay and vegetables alone. Choose a timothy-based pellet with added vitamin C. Wild Harvest Advanced Nutrition Guinea Pig Food and Vitakraft Menu Guinea Pig Pellets are both solid options. Feed approximately ⅛ cup per guinea pig per day. Avoid muesli-style mixes with seeds and dried fruit.

Vitamin C Supplementation

Even with a good diet, many guinea pigs benefit from additional vitamin C supplementation. Oxbow Natural Science Vitamin C Supplement is a vet-recommended option made with timothy hay — it's palatable and easy to incorporate into the daily routine. Do not add vitamin C to water, as it degrades quickly and may make the water taste unpleasant.

Treats

Treats should be given sparingly. Oxbow Simple Rewards Apple Banana Treats are a healthy, low-sugar option made with timothy hay. VESPRO Timothy Hay Sticks are another excellent treat that also supports dental health. Avoid sugary commercial treats, yogurt drops, and anything with artificial additives.

Fresh Water

Fresh water must always be available. Use a no-drip water bottle and change the water daily. Clean the bottle weekly to prevent bacterial buildup.

Foods to Avoid

• Iceberg lettuce — causes diarrhea
• Onions, garlic, leeks — toxic
• Avocado — toxic
• Rhubarb — toxic
• Potatoes — too starchy
• Dairy products — guinea pigs are lactose intolerant
• Meat — guinea pigs are herbivores

Conclusion

Feeding a guinea pig properly means unlimited hay, daily fresh vegetables rich in vitamin C, measured pellets, and clean water. Vitamin C is the most critical nutritional consideration — ensure your guinea pig gets it every day through fresh bell pepper, leafy greens, or a quality supplement.