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Home > Hamsters > Can Hamsters Eat Onions? Vet Approved Nutrition Advice

Can Hamsters Eat Onions? Vet Approved Nutrition Advice

red onions on wooden table

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Dr. Karyn Kanowski

Veterinarian, BVSc MRCVS

The information is current and up-to-date in accordance with the latest veterinarian research.

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Hamsters are partial to munching on bits of fruits and veggies, but there are certain food items that should always be avoided. Onions, for example, should never be fed to hamsters because they can make them very unwell.

Read on to find out why hamsters cannot eat onions and to learn more about safe and unsafe foods for hamsters.


Why Can’t Hamsters Eat Onions?

Just because hamsters eat a variety of vegetables, doesn’t mean every kind is safe. The reason onions are not safe for hamsters is that they contain compounds that turn into disulfides, which can result in a condition called hemolytic anemia—the destruction of the red blood cells. For the same reason, hamsters should not eat garlic, spring/green onions, shallots, leeks, or chives.

What Is a Suitable Hamster Diet?

Hamsters are omnivorous animals that require a diet consisting of quality hamster pellets (you can buy these in pet stores or online), fresh leafy greens and vegetables, with some fruit in moderation. When picking hamster pellets, avoid colorful, muesli-type mixes, as these tend to encourage pickiness, meaning the hamster won’t get all the nutrients they need.

As for fruits and vegetables, be careful not to go overboard because, in large amounts, these can cause an upset stomach. About half a tablespoon per day should be just about right. To add variety, you can cut a few fruits and veggies into tiny pieces and make a cute mini hamster salad! You can also give your hamster some fiber-packed timothy hay to nibble on as a supplement, as well as something to dig and burrow in.

Care should be taken to ensure that the diet is balanced and varied so the hamster gets a good mix of nutrients, and you can treat them to protein-filled snacks in small amounts now and again, like mealworms, grasshoppers, crickets, tofu, lean chicken, or boiled eggs. Sunflower seeds are also common treats, but be careful as they are deceptively high in fat. Clean water should be on offer at all times.

hamster eating inside his cage
Image Credit: RaquelVizcaino, Shutterstock

Which Vegetables Can Hamsters Eat?

Though onions and other members of the allium family are off the menu for hammies, they can still indulge in a huge range of safe veggies and greens. Here’s a list for your convenience:

  • Asparagus
  • Cauliflower
  • Broccoli
  • Carrots
  • Bok choy
  • Spinach
  • Chicory
  • Cress
  • Bell pepper
  • Dandelion
  • Clover
  • Swiss chard
  • Kale
  • Basil
  • Parsley
  • Zucchini
  • Pumpkin
  • Collard greens
  • Corn
  • Squash
  • Romaine lettuce

Note: It’s wise to give veggies a wash before you feed them to your hamster, and don’t forget to only offer them in small quantities to prevent an upset tummy. Rotate veggies and greens for variety and balance.

hamster eating pixabay
Image Credit: mordilla-net, Pixabay


Which Fruits Are Safe?

Plenty! Again, remember to feed fruits in moderation because, while they’re a great source of vitamins and minerals, they are also high in natural sugars. Fruit in large quantities opens your hamster up to developing health issues. In small amounts and as part of a varied diet, the following fruits are safe:

  • Apples
  • Pears
  • Papaya
  • Bananas
  • Cranberries
  • Blueberries
  • Blackberries
  • Raspberries
  • Grapes
  • Kiwis
  • Mangos
  • Melons
  • Peaches
  • Strawberries
  • Plums

Note: Remove any seeds, pits, stones, rinds, stems, or leaves before offering any of these to your hamster.

White hamster eating raspberry_PiotrLukasik_shutterstock
Credit: PiotrLukasik, Shutterstock


Which Foods Are Unsafe?

As is the case with allium family vegetables like onions, a number of other fruits, vegetables, and miscellaneous foods are unsafe for hamsters. Some are toxic while others are likely to cause digestive upset. These include:

  • Onions
  • Leeks
  • Garlic
  • Chives
  • Spring onions
  • Uncooked kidney beans
  • Raw, green potato
  • Eggplant
  • Hot peppers
  • Rhubarb leaves
  • Tomato plants
  • Chocolate
  • Iceberg lettuce
  • Citrus fruits
  • Fruit seeds, stones, pits, rinds, or leaves
  • Spicy, sugary, or salty foods
  • Packaged meats
  • Bitter almonds
  • Whole celery stalks (choking hazard)
  • Salted peanuts
onions and garlics
Image Credit: Shutterbug75, Pixabay


Final Thoughts

Never feed onions or any other allium family member to your hamster because it could damage their red blood cells. Instead, stick with safe vegetables and greens like broccoli, Swiss chard, basil, and Bok choy. Making sure your hamster enjoys a varied diet is essential to keeping them as healthy and content as possible.

Featured Image Credit: Bukhta Yurii, Shutterstock

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