Can Guinea Pigs Eat Onions? (All the Information)

Can guinea pigs eat onions?

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Guinea pigs are very popular pets that need healthy foods to grow strongly. However, many pet owners may try to give them foods like onions, mistakenly thinking that they may be good for them. After doing a lot of research on whether guinea pigs can eat onions (including talking with veterinarians), we’ve come to the conclusion that it’s best to keep your pet away from this food.

Can Guinea Pigs Eat Onions?

No, you shouldn’t feed guinea pigs onions.

This food can cause serious health problems, including digestive issues, that can threaten your guinea pig’s life.

However, if you do read this whole article, you’ll learn more about what kind of health problems onions cause and what alternate foods you can give your guinea pig to keep it safe.

Can Guinea Pigs Eat White Onions?

Guinea pigs cannot safely eat onions, even at small levels. That’s primarily because of a chemical known as disulfide. This chemical causes the irritation people experience when cutting onions but is more potent in poor guinea pigs. It can cause a variety of minor reactions, including:

  • Irritation in the eyes that may upset a guinea pig
  • Heavy salivation that may be annoying to you and the guinea pig
  • Nose secretions that can also affect a guinea pig’s comfort

However, onions can also cause more serious health problems for your guinea pig, such as extreme digestive discomfort and serious respiratory issues. Some guinea pigs may even fall into respiratory distress, which could threaten their lives. These conditions could occur at any time and at very low serving levels.

As if it couldn’t get any worse, onions can also cause problems like anemia by affecting a guinea pig’s red blood cells and causing poor immune system health and excessive fatigue. Even small amounts of onions can trigger some adverse reactions in guinea pigs that may affect their overall health.

Can Guinea Pigs Eat Red Onions?

Picture of red onions

While red onions are a little different than white onions, they also have disulfide and other chemicals that can cause serious health problems. Red onions have an even higher risk of causing anemia, which can lead to serious organ death in guinea pigs if it worsens. Simply put, it’s best to avoid red onions and find alternatives that your guinea pig may not just enjoy more but which won’t threaten its health.

Can Guinea Pigs Eat Green Onions or Shallots?

Green onions (scallions) and shallots are also not good for your guinea pig and contain the same kind of dangerous chemicals that may affect their health. Furthermore, green onions (along with other onion types) have high calcium and phosphorous content. While guinea pigs need both of these nutrients, onions have far more phosphorous than calcium, which is not a good balance for your guinea pig.

Nutritional Value

The frustrating thing about onions and guinea pigs is that this food has a lot of nutritional value that would be good for the guinea pig without the danger. Unfortunately, the adverse impact of onions is far too high to tolerate and is not worth risking your guinea pig’s life. Just a few reasons why onions are healthy include:

  • Low calorie count of 64 per 160 grams
  • About 1.74 grams of protein
  • Very low fat content of 0.1 grams
  • Decent fiber content of 2.7 grams
  • Healthy sodium content of 6 milligrams
  • Good vitamin C level of 7.4 milligrams

While these nutrients are important for your guinea pig’s health, there are other ways that you can get them beyond an onion. We’ll highlight some of these methods in a later section to ensure that you understand which method is the best option for your guinea pig.

Considering the Different Onion Parts: Can Guinea Pigs Eat Onion Skins?

We already discussed why your guinea pig shouldn’t eat white, red, or green onions. But are there any onion types that are healthy for them? Unfortunately, onions simply aren’t a good choice for your guinea pig, and no onion type or part is safe for your guinea pig.

That means things like the skin shouldn’t be fed to your guinea pig, even if they seem less potent than the meat of the onion. All parts of the onion contain dangerous chemicals and should be kept away from your guinea pig, even if they seem interested in or even enjoy onion skins.

Alternatives to Eating Onions for Guinea Pigs

If you want foods that have a similar texture, taste, or nutrient level to onions for your guinea pigs, there are thankfully many that are very healthy. Some of the most popular onion alternatives for guinea pigs include:

  • Romaine Lettuce – This lettuce is one of the healthiest foods for guinea pigs and contains high amounts of fiber and vitamin C but also has very few calories. Guinea pigs also love it. That makes this a great staple food for your guinea pigs or one you can use as a snack.
  • Carrots – Carrots contain high levels of vitamin A, vitamin C, fiber, and beta-carotene. They help a guinea pig produce vitamins and improves their overall digestion. Carrots can work well as a staple food or an occasional snack, depending on your guinea pig’s preference.
  • Sweet Potatoes – These healthy potatoes have high fiber, potassium, and vitamin C levels. They also maintain a guinea pig’s blood pressure and taste really good as a raw cubed snack. Guinea pigs like chewing on these potatoes at least once or twice per week.
  • Cucumber – Cucumbers have a satisfying crunchiness that guinea pigs love and they provide a good source of vitamins and minerals and a healthy water content. They should be eaten as a treat because they can cause an upset stomach if the guinea pig eats them every day.
  • Broccoli – This popular vegetable is very high in antioxidants, vitamin C, B5, and A and is a great fiber source. It’s also surprisingly high in protein, making it a great option for guinea pigs. That higher fiber content does make it important to limit this to a snack or treat.
  • Cauliflower – Cauliflower has similar nutrient contents to broccoli but has a different taste. It is also rich in vitamin C and fiber, as well as calcium and other healthy minerals. Try to serve it to your guinea pigs no more than twice a week to keep them as healthy as possible.

Recommended Food and Treats for Guinea Pigs

Healthy guinea pig foods and treats come in many varieties and provide your pet with a variety of tastes and vitamins. Make sure to follow any special serving instructions included in each section:

  • Hay – Hay works well as a food alternative for your guinea pig if you run out of normal food. Meadow hay is a good option, though Timothy and Orchard Grass hay are the best.
  • Fresh Grass – If you can’t find hay in your area, you can give your guinea pig fresh grass pulled right from your yard. Make sure that it hasn’t been treated with dangerous chemicals before picking it.
  • Kale – Kale is a popular food for guinea pigs because it is high in fiber and vitamin C and is often more filling than hay and grass. It does tend to spoil quicker, though, so be careful when serving it.
  • Spinach – Guinea pigs love spinach but it should be served in moderation because it can cause bladder stones. However, it makes a good weekly snack in small amounts.
  • Celery – Celery works well as either a snack but needs to be carefully prepared. Remove the strings from each stalk and serve it no more than 2-3 times per week to avoid bladder stones.
  • Bell Peppers – Unlike onions, bell peppers are a very healthy food and snack for guinea pigs, as long as you de-seed them and serve them no more than 2-3 times per week.

Foods to Avoid Giving Guinea Pigs

Though guinea pigs are adaptable to many types of foods, there are many others that you simply cannot give them. Doing so threatens their health and could even kill them. The following foods are all things that you should avoid giving your guinea pig if you want to ensure their overall health:

  • Seeds
  • Nuts
  • Cereals
  • Grains
  • Buttercups
  • Corn
  • Peas
  • Grains
  • Avocado
  • Garden shrubs
  • Onion grass
  • Sweet peas
  • Mushrooms
  • Rhubarb
  • Pickled foods of any type (even foods they can normally eat)

You should also avoid giving them most plants and trees, including lilies, nightshade, garden shrubs, foxglove, oak, and daffodils. Guinea pigs are also not suited to foods like biscuits, breads, sugars, sweets, dairy products, chocolates, crackers, pasta, or any kind of meats.

Focus on either the foods listed in the previous section or on guinea pig food purchased from a pet food shop. You don’t want to run the risk of affecting your guinea pig’s overall digestive health by giving them onions or other foods that may poison them in unfortunate ways.

Frequently Asked Questions

Additional Sources & Resources

We also have a number of other guides related to guinea pigs, including:

And here are some informational sources & resources related to guinea pig nutrition:

  • “Guinea Pigs: A Complete Pet Owner’s Manual” by Katrin Behrend and Susan A. Smith. This book provides comprehensive information about guinea pigs, including their dietary needs and the potential dangers of certain foods, such as onions.
  • “Small Animal Clinical Nutrition, 5th Edition” by Michael S. Hand, DVM, DABVP, and Richard W. Nelson, DVM, DACVIM. This book is a reference guide for veterinarians and includes information about the nutritional requirements of guinea pigs and the potential risks of feeding them onions.
  • “Exotic Animal Formulary, 4th Edition” by James W. Carpenter. This book is a comprehensive guide to the care of exotic animals, including guinea pigs. It includes information about the potential hazards of feeding guinea pigs onions and other toxic foods.
  • “The Domestic Guinea Pig: Biology, Behavior, and Health Care” by Susan A. Brown. This book provides detailed information about the biology, behavior, and health care of guinea pigs, including the potential dangers of feeding them onions and other toxic foods.
  • “Guinea Pigs: A Complete Pet Owner’s Manual” by Marcy Cottrell Houle. This book offers practical advice for guinea pig owners, including information about the potential risks of feeding these animals onions and other toxic foods.

Pet News Daily Staff
Pet News Daily writers are experts in pet care, health and behavior. We are members of Society for Professional Journalists and practice ethical journalism.