The Science Behind Gut Loading For Tarantulas

gut loading tarantulas
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Despite the fact that most of us want to make sure our tarantulas get the very best care, many of us are not speaking about gut loading and the nutrition of these creatures!

Is it just enough to feed your tarantulas some bugs? If you’re feeding your tarantulas bugs that are safe and nutritious for them, you may be tempted to believe you’ve done the best you could do. But gut loading can be so useful! Gut loading is very common and a technique that is used all over the exotic pet hobby. Gut loading is where you would pay special attention to the nutrition of your tarantulas’ feeders – making sure they get the best nutrition- so that these nutrients can be passed along to your tarantula during feeding time.

Now, gut loading isn’t a MUST you have to do. Many people never gut load their feeders and their tarantulas are healthy. However, if we imagine how our bodies are impacted by the food and nutrition that the animals we eat have eatten (unless you’re vegan), it must work the same way.

In my experience, I have always given my feeders slices of fruits and vegetables. Some give them other things such as cereal as these guys will eat anything, but I try to pay attention to the water and vitamin content for my spiders. At any rate, a nutrient dense diet given to the feeders would likely translate to better health for your tarantula, and I believe there’s a better probability of nutrients moving if it comes from a fruit or vegetable.

Now, this is all theory. We don’t actually know or have much information about whether or not tarantulas are even able to synthesize or utilize the vitamins or nutrients from human food. However, that shouldn’t discourage us from trying.

Jamie from Jamie’s tarantulas gave some amazing advice about why one should consider gut loading feeders:


Another question that I am frequently asked is, “Jamie, how do I ensure that my tarantula is receiving sufficient hydration?” That is a wonderful question. Oftentimes, people feed roaches to their tarantulas without forethought as to whether or not the roach itself is hydrated. One method of safeguarding against dehydration is to “gut load” your roaches prior to feeding them to your tarantula. Gut loading is merely feeding your roaches fresh fruit and vegetables ( versus roach chow alone) in order to maximize their water intake. I strongly believe that hydration is more important than relative humidity in the enclosure for a successful molt.


1) The tarantula(s) can reach its full genetic size (remember, as mom would say: eat your greens to grow big and strong).


2) Undernourished tarantulas lack the vibrancy/coloring that their well-nourished counterparts exhibit.


3) It’s possible to increase growth rate, while decreasing the amount of food that the tarantula is fed. This is also why pet stores sell higher quality dog/cat food in smaller portions (the higher the quality, the smaller the portion sizes needed to ensure proper nutrition). 


4) Improvement in overall health. If you were to eat only junk food every day, you would most likely feel rather lethargic, stressed, or just plain blah! Same goes for tarantulas. A tarantula that eats organically fed roaches will be less stressed! 


5) Increased hydration. A well hydrated tarantula is more likely to have a successful molt. Tarantulas that are not adequately hydrated can die during a molt. 

Another very important point about gut loading feeders is that the food should be pesticide free or organic due to preventing your feeders and tarantula from getting sick and taking on any chemicals the food was contaminated with.

While we may not have tons of data on this, gut loading the feeders won’t hurt! I hope this was helpful 🙂