Can Guinea Pigs Eat Spinach?

As many guinea pig owners will know, guinea pigs need leafy greens as part of their daily diet.

This got me wondering about whether spinach was a suitable leafy green for guinea pigs to eat.

So, can guinea pigs eat spinach?

Yes, Guinea pigs can eat spinach.

Spinach is high in vitamin C and other essential nutrients, and is low in sugar. However, only feed it once or twice a week because spinach is high in oxalates, which can cause kidney stones.

While researching this topic, I also looked into what are the best leafy greens to feed your guinea pigs, and which can be fed on a daily basis.

Read on to find out more information.

Spinach Diet Pros And Cons

Spinach is a good vegetable to give guinea pigs because it’s a leafy green that can make up a good portion of their diet.

However, as I mentioned above, it should be avoided in large quantities because of the nutrients it contains.

Most people know that spinach is high in iron. After all, that’s why many people try and get plenty of it in their diets.

However, the iron levels in spinach can be harmful to guinea pigs, and can lead to a range of blood disorders.

While we can deal with the levels of iron, they’re far too high for guinea pigs to eat in large quantities.

Another reason why you should avoid overfeeding your guinea pigs spinach is because it’s high in calcium and a compound called oxalates.

Guinea pigs have very sensitive digestive systems, and too much of either of these nutrients can lead to bladder or kidney stones, which are painful and difficult to manage without surgery.

Guinea pigs need a balance of both of these nutrients, but the emphasis is on a balance.

Too much of either will lead to stones, and so you should be careful overfeeding them vegetables that contain either. As spinach is high in both, it’s best to careful with how much you give.

However, it’s also worth noting that spinach is high in vitamin C, which is something your guinea pigs need in quite large quantities.

For this reason it’s great as part of their diet, but should be supplemented with a range of other leafy greens.

As with all other vegetables, spinach should be washed properly before feeding it to your guinea pigs.

This will help remove any pesticides and other chemicals sprayed on the spinach during growing and packaging.

Also, remove any large stems from the leaves as these can lead to bloating and stomach issues.

Although it might be tempting to stock up on frozen spinach, this should be avoided, as should cooked spinach in general.

Guinea pigs can only process raw vegetables, and anything cooked can lead to constipation or other stomach issues. Raw spinach isn’t exactly expensive, and if you’ve bought some for yourself, just save a bit to one side for your guinea pigs.

What Vegetables Or Leafy Greens Are Best For Guinea Pigs?

If, like me, you feel a bit confused by the term “leafy greens”, it can be difficult to know what falls under this term.

Considering guinea pigs need careful attention when it comes to their diet, it can be useful to know what counts as a leafy green. Here are my top suggestions:

  • Lettuce
  • Endive
  • Rocket
  • Corn husks
  • Chard
  • Brussel sprouts
  • Chicory
  • Parsley

Lettuce is something you need to be careful with however. Some types of lettuce (such as iceberg) have a very high water content, and so should be avoided if you don’t want upset stomachs.

It’s best to stick to leafy types of lettuce, such as romaine, cos, radicchio, and so on. Even with these, I’d recommend cutting off the larger stalks because these will be very watery.

As with spinach, many of these leafy greens contain high levels of iron, and some are high in calcium and oxalates.

Be careful feeding these in large quantities, and limit them to two or three times a week just to be on the safe side.

Leafy greens such as romaine lettuce, chicory, and endive are fine to be fed on a daily basis.

You can also feed your guinea pigs things like dandelion leaves on a daily basis because these are pretty safe from a nutritional perspective. Obviously just make sure everything is washed properly first.

It’s important to not leave leafy vegetables lying around in your guinea pig’s cage for too long. I tend to remove any uneaten greens at the end of the day when I’m putting them to bed.

Unlike watery foods, such as strawberries and tomatoes, leafy greens aren’t as much of a problem for bacteria and flies, but you should always remove them before they start to spoil.

How Much Spinach Can I Give My Guinea Pig?

The bulk of your guinea pig’s diet should be made up of hay and guinea pig pellets. These will provide enough carbohydrate and protein, but should always be supplemented with fresh fruit and veg to provide variety and interest.

As a general rule, I work on a cup of fresh fruit and vegetables a day. The majority of this should be made up of leafy greens, such as spinach.

For example, I take a cup and fill it most of the way with spinach, and then add on a few pieces of fruit just to fill the cup.

If you think of a cup measurement, and the recommended daily allowance of fruit or veg (for example, one tomato is enough per guinea pig), and then take away this amount from the size of a cup, you have a good idea of how much spinach you should be feeding them.

There’s generally very little danger from overfeeding your guinea pigs leafy greens like spinach from a calorie perspective, as most of them are low in calories.

However, as I mentioned, spinach is high in nutrients that can be damaging to a guinea pig, and so you do need to be conscious of how much you’re giving, and how often.

How Much Iron Do Guinea Pigs Need?

Iron is an essential nutrient for almost every animal because it helps keep blood healthy.

Iron is one of the essential components in hemoglobin, which is found in red blood cells.

As guinea pigs are red-blooded animals, they obviously need iron to stay healthy. But how much iron do guinea pigs need?

Guinea pigs need around 50mg of iron per kg of diet to remain healthy. To put this into context, they need around 150g of fiber a day, which is their most important nutrient.

Guinea pigs only need the tiniest amount of iron on a daily basis to stay healthy, and by this I mean around 4-5mg.

Spinach has around 0.8mg of iron per cup, which might not sound like much, but if you feed your guinea pigs spinach on a daily basis then it won’t take long to build up in their system.

That’s why I recommend feeding spinach once or twice a week, as this should cover their standard iron needs.

Also, you have to remember that other foods contain iron, and so you shouldn’t just work on spinach as their only source.

For example, brussel sprouts have around 1.2mg of iron per cup, which is more than spinach and would be a dangerous level for guinea pigs if consumed too much.

Too much iron can lead to complications with the blood. It can make guinea pigs very ill and any iron-related conditions are usually hard to diagnose without the help of a vet.

For this reason you should be aware of how much iron you’re feeding your guinea pigs to make sure you don’t overdo it.


So I found that guinea pigs can eat spinach, and that it’s a great choice as one of their leafy greens.

However, avoid feeding them too much because the nutrients can become harmful if given in high quantities.

For daily feeding, stick to lettuce such as romaine, and give spinach two or three times a week.

Related Questions:

Can guinea pigs eat too much? Yes, guinea pigs are very prone to obesity, and so their diet needs to be carefully controlled. Too much fresh grass can lead to bloat, which is painful and essentially untreatable.

Can grapes kill guinea pigs? There doesn’t seem to be a conclusive answer for this, but some vets believe grapes can lead to kidney problems. To be on the safe side, just avoid feeding your guinea pigs grapes.

Can guinea pigs eat pineapple? Guinea pigs can eat pineapple, but be very careful about feeding it. Pineapple contains an acid that can lead to mouth sores, so limit to a maximum of once a week, but I only give it once a month if I happen to have any spare.