Tomatoes (scientifically known as Solanum Lycopersicon) are part of the nightshade family, which includes potatoes, eggplants (aubergines), and bell peppers.
Tomatoes are botanically a fruit, but they’re commonly classified as vegetables due to their culinary use.
Tortoises can eat ripe tomatoes as a source of hydration, when giving them oral medication, as a training reward, or as an occasional treat.
Unripe tomatoes and other parts of the plant (the leaves, stem, and tops) are poisonous due to their high concentration of solanine and tomatine.
The problem with feeding tomatoes to tortoises is more related to their toxicity than their digestibility.
Can You Feed Tortoises Tomatoes?
Unripened tomatoes should never be eaten, but a tortoise is unlikely to get sick if it eats ripe tomatoes.
However, regularly giving tomatoes to a tortoise is inadvisable, as they have little nutritional value relative to other fruits. Also, the plant itself contains naturally occurring glycoalkaloids.
Tropical tortoises are adapted to savannahs and rainforests with many fruits, stems, and flowers. These species include yellow-foots, red-foots, African spurred, Russian tortoises, and leopard tortoises.
Their digestive systems have developed to handle fruit consumption. The diet of red-footed and yellow-footed tortoises consists of up to 50% fruit, but other torts shouldn’t consume more than 10%.
However, tortoises from areas with little or no fruit trees are more suited to digesting grasses and leaves, including Sulcata tortoises, Russian tortoises, Hermann’s tortoises, and desert tortoises.
If a non-fruit-eating species of tortoise eats tomatoes, it could cause digestive distress.
Types of Tomatoes Tortoises Like
Several different types are suitable for tortoises, including the following:
- Grape tomatoes: Small, sweet, and juicy tomatoes.
- Roma tomatoes: Small, oblong-shaped tomatoes with fewer seeds and less juice.
- Cherry tomatoes: Small, round, sweet, and juicy tomatoes.
- Beefsteak tomatoes: Large, meaty tomatoes that reach up to 6 inches.
- Heirloom tomatoes: Non-hybrid tomatoes are available in various shapes and colors.
- San Marzano tomatoes: Medium-sized, elongated tomatoes low in seeds and juice.
Always wash tomatoes thoroughly to remove pesticides before offering them to a tortoise.
Are Tomatoes Good for Tortoises?
Whether tomatoes are healthy depends on the amount and the part of the plant consumed.
Safety
The tomato, when ripe, is okay for tortoises but not that healthy. However, regardless of the species, unripe tomatoes are toxic to tortoises because they contain a lot of tomatine and solanine.
According to the National Library of Medicine, tomatine and solanine are antimicrobial.
Consequently, they have adverse effects on animals when ingested. Solanine, which is found in all plants in the nightshade family, is the more dangerous of the two compounds.
When ingested in large amounts, it can cause neurological and gastrointestinal complications, like:
- Nausea
- Diarrhea
- Vomiting
Tomatine is a less toxic alkaloid with enough fungicidal and antimicrobial properties to cause sickness when ingested in large quantities.
It affects the cell membranes and disrupts neurotransmitters, resulting in lethargy, vomiting, and diarrhea. It can even result in liver and kidney damage.
Tomatine and solanine are present in varying levels throughout the entire tomato plant.
The lowest concentrations of tomatine and solanine occur in the fruit, although unripe fruits contain much higher amounts. The toxicity levels are highest in the leaves and stems.
Nutritional Value
Below are the main nutrients found in tomatoes:
- Vitamin K1 – Primarily involved in promoting blood coagulation and clotting in case of injury, but also keeps the bones (skeleton) and shell strong.
- Potassium – This regulates blood pressure, supports muscle and nerve function, and maintains optimal fluid balance in the body.
- Vitamin B9 – Folate is the main compound in the growth and development of new blood cells.
- Lycopene – This antioxidant prevents cell damage and degeneration. Also, it slows down age-related bone degeneration, which keeps a tortoise more active for longer.
- Insoluble fiber – It improves bowel health and prevents constipation.
- Vitamin A – Retinol is important for vision, skin health, and the immune system.
Tomatoes are also a good source of vitamin C, but reptiles don’t need a dietary source.
Like other reptiles, their bodies can produce vitamin C through gluconeogenesis, as they can synthesize vitamin C from glucose.
Water makes up more than 95% of an average ripe tomato. With dehydration being one of the main causes of health problems, giving tortoises foods high in water can’t be understated.
Are Tomatoes Bad for Tortoises?
Tomatoes may not be the healthiest foods for tortoises, but they aren’t toxic unless unripe.
The most common argument against fruit consumption is their high fructose levels, which are said to increase the risk of obesity, but this isn’t the case with tomatoes.
However, according to the Journal of the Science of Food and Agriculture, the levels of fructose and glucose aren’t as high in ripe tomatoes as in unripe green tomatoes.
As with everything else, excessive consumption of tomatoes can be harmful. Most tortoises aren’t fully adapted to eating fruits, so they can experience digestive distress if they eat too many.
The sweet and juicy nature of tomatoes makes them addictive. If a tortoise gets used to them, it may refuse to eat essential foods like greens, vegetables, and flowers.
Are Tomato Seeds Safe for Tortoises?
The seeds have low solanine and tomatine levels, but only if the tomato is ripe.
Unfortunately, tomato seeds can carry the tomato brown rugose virus. The effects on reptile health aren’t yet known, but it’s likely to cause stomach upsets when ingested by tortoises.
However, according to Biomedicine Pharmacotherapy, the seeds contain healthy macromolecules, ranging from proteins to phytochemicals and polysaccharides. These macromolecules may have antioxidant and antimicrobial roles, depending on their concentrations.
Tomato seeds are safe for tortoises, provided they come from healthy tomatoes.
How Many Tomatoes Can A Tortoise Eat?
Depending on the species, the recommended fruit consumption for tortoises is 5-10% of their diet. Since there are other healthier fruit options, you should only offer a tortoise tomato occasionally.
According to the Uppsala University of Sweden, it takes 6-13 days for tomato seeds to pass through a tortoise’s gut. This means you should only give fruit-eating tortoises 1 tomato every 2 weeks.
Conclusion
Although ripe tomatoes are safe for fruit-eating tortoises, they’re not the healthiest fruit.
However, pet tortoises eat tomatoes, so owners use their lure to get their pets to take oral medications. Also, if a tortoise isn’t hydrating properly, tomatoes can be a good way to increase its water consumption.
Tortoises shouldn’t eat unripened tomatoes or other parts of the plant due to solanine and tomatine. Too much of any variety of tomatoes can lead to digestive problems due to their sugar content.
All the nutrients in tomatoes are in higher quantities in grasses, plants, flowers, and leafy greens, which should comprise at least 80% of a healthy tortoise’s diet.
