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are tortoises allowed spinach?

Is Spinach Good For Tortoises?

Tortoises need a diet that mostly consists of grasses, leafy greens, and vegetables. Spinach seems like a natural choice since it’s a favorite leafy green among humans.

Spinach is high in vitamins, minerals, and antioxidants. However, it also contains oxalates, which work as anti-nutrients that can leach out calcium from your tortoise.

In large amounts, spinach can lead to kidney stones, calcium deficiency, and irritation in the mouth and throat of your tortoise.

In small quantities, spinach can strengthen your tortoise’s eyes, immune system, skin, and bones. It’ll also improve blood clotting, cell growth, and tissue health.

If you want to be extra safe, offer spinach alongside foods with fewer oxalates, such as kale, bok choy, broccoli, sweet potato, blueberries, and blackberries.

Are Tortoises Allowed Spinach?

Spinach isn’t considered toxic or poisonous to tortoises. In fact, it’s packed with a high amount of calcium, which is vital for bone and shell growth.

A tortoise’s shell is a part of its overall skeleton, which means that young tortoises need more calcium during their early development. Without it, they can become vulnerable to shell pyramiding and other degenerative conditions.

Tortoises also need vitamins that strengthen their eye and skin health as they grow. Luckily, spinach is also high in vitamins, such as:

  • Vitamin A
  • Vitamin C
  • Vitamin K1
  • Vitamin B9

Even so, spinach should be given in small amounts. It should not make up the bulk of a tortoise’s regular diet. That’s because spinach is not a perfect source of calcium, despite the amount it contains.

This is due to the oxalates present in the plant, which can stop tortoises from absorbing calcium. It’s even been linked to the formation of kidney stones.

do tortoises like spinach?

Do Tortoises Like Spinach?

Some tortoises love spinach, while others ignore it. This will depend on the species of tortoise, as well as its personality. Overall, spinach has a crunchy texture and a strong flavor. Grazing tortoises, like sulcatas and Hermann’s, thrive on leafy greens that have these qualities. They are known to love munching on spinach.

Can Tortoises Eat Spinach Leaves?

Tortoises can eat spinach leaves, and it is safe to add them to your tortoise’s diet in moderation. They can be ripped up and sprinkled over other food or included by themselves as a treat.   Spinach has many health benefits. Just make sure to fill your tortoise’s diet with other, low-oxalate plants.

Spinach Nutrition FactsIn 100 g of raw spinach
Calories23 kcal
Protein3 g
Carbs3.6 g
Fat0.4 g
Sugar0.4 g
Fiber2.2 g
Water91%

Vitamins And Minerals

Spinach contains many vitamins that your tortoise will absorb. Some include:

  • Vitamin A: Improves eye health
  • Vitamin C: Boosts the immune system and keeps the skin healthy
  • Vitamin K1: Helps blood clot
  • Vitamin B9: Speeds up the healthy growth of tissue, and keeps cells functioning properly

Spinach also contains iron. This mineral helps blood cells transport oxygen throughout the body. It’s also high in calcium. However, the presence of oxalates can hinder its bioavailability.

Antioxidant Rich

Spinach has many compounds that contain antioxidant properties. Antioxidants are important for relieving and preventing oxidative stress. Oxidative stress has been linked to chronic and age-related diseases, including:

  • Cancer
  • Diabetes
  • Cardiovascular diseases

Oxidative stress is caused by free radicals, which are naturally present in the environment. This makes them hard to avoid, so repairing them with antioxidants is essential. The main antioxidants found in spinach include:

  • Lutein
  • Zeaxanthin
  • Quercetin 
  • Kaempferol

Prevents Cancers

Spinach contains two compounds that slow the growth of cancer cells. Namely, these are the compounds MGDG and SQDG. In humans, these have been shown to halt tumor growth and even decrease tumor size. They can also safeguard against prostate and breast cancer.

The benefits can also be found in animal studies. According to Molecular Nutrition and Food Research, spinach can suppress the formation of cancer cells in rats. While reptile studies are limited, there is reason to believe this advantage may carry over to tortoises.

High In Carotenoids

Spinach is rich in carotenoids, which are a type of antioxidant with their own unique properties. When ingested in the body, carotenoids are turned into vitamin A.

While some tortoises can generate their own vitamin A, omnivorous tortoise species cannot. This means they have to rely on their diet for vitamin A, and spinach can help.

Is Spinach Toxic To Tortoises?

Spinach is not toxic to tortoises. However, you should limit how much you feed your tortoise because of the oxalates found in spinach.

Oxalates are derived from oxalic acid, which is a naturally occurring compound that can be found in almost all plants. This is especially true for leafy greens, vegetables, fruits, and nuts. 

However, spinach contains exceptionally high amounts. Oxalates are not inherently toxic to tortoises, but they can lead to damaging effects on the body.

is spinach toxic to tortoises?

Reduces Mineral Absorption

Oxalic acid is an anti-nutrient. As the term implies, an anti-nutrient prevents the body from absorbing nutrients as efficiently as possible. Oxalic acid does this by binding to certain minerals, notably calcium and manganese.

The oxalic acid in the spinach will bind with the calcium also found in the spinach. It then forms calcium oxalate. The body cannot absorb or use calcium oxalate, so it is excreted as waste. If your tortoise eats a large amount of spinach, then oxalic acid may not limit itself to sapping calcium from the spinach alone.

It can remain in the body and leach calcium from bones and other foods that your tortoise eats. According to the American Journal of Clinical Nutrition, the presence of oxalates hinders calcium absorption when spinach is eaten excessively. For this reason, spinach should never become a staple food for your tortoise.

Irritates Mouth And Throat

The oxalates in spinach contain raphides. These are crystals made out of calcium oxalates that can be found in certain plants. These crystals are needle-shaped, which means that they can easily get caught in the throat and mouth. When ingested in large amounts, raphides can irritate the digestive tract, causing pain in tortoises.

Forms Kidney Stones

The body naturally excretes oxalates. However, there are instances wherein they stay in the gut and form kidney stones. According to the New England Journal of Medicine, about 80% of kidney stones are composed of calcium oxalate.

Of course, the risk of developing kidney stones varies between tortoise. That’s because oxalates are regulated by gut bacteria, most notably oxalobacter formigenes. There’s a greater chance of calcium oxalates failing to be excreted from the body when there aren’t enough gut bacteria.

There’s also evidence to suggest that as long as your tortoise remains hydrated, kidney stones shouldn’t be a problem. A known cause of kidney stones is low urine output.

According to Nephron, high fluid intake can prevent kidney stones from recurring. As long as your tortoise remains hydrated and doesn’t eat too much spinach, the risk for kidney stones should be minimal.

Spinach is good for tortoises in small amounts. As long as it doesn’t become a meal staple and isn’t fed as more than a treat, the vitamins, minerals, and antioxidants will keep your tortoise healthy.