If you have a gecko, you have probably stared at a cup of wriggling mealworms at the pet store and wondered: can my gecko eat these? The short answer is yes, most commonly kept geckos like leopard geckos, crested geckos, and African fat-tailed geckos can eat mealworms. But there is a catch. Mealworms are not a perfect food. They are like the fast food of the insect world: tasty, easy, but not something you want your pet to live on. In this guide, we will break down exactly how to feed mealworms to your gecko safely, which geckos should avoid them, and how to balance them with other foods to keep your reptile healthy and happy.

Are Mealworms Safe for Leopard Geckos?

Leopard geckos are insectivores, and mealworms are one of the most popular feeder insects for them. They are safe to feed as long as you follow a few basic rules. The main concern is that mealworms have a hard, chitinous exoskeleton. For adult leopard geckos, this is usually not a problem, but for baby or juvenile geckos, the tough shell can be difficult to digest and may cause impaction, especially if the gecko is not kept on proper substrate. If you are setting up a new home for your gecko, choosing the right tank setup matters. A good leopard gecko tank with a solid, safe substrate like tile or paper towels can reduce the risk of accidental impaction from swallowed bedding. Always feed mealworms in a shallow dish so your gecko does not accidentally eat loose substrate along with the worm.

Nutritional Value: The Good and the Bad

Mealworms are about 20% protein and 13% fat, which makes them higher in fat than crickets or dubia roaches. This is why they are best used as a treat, not a staple. Feeding too many mealworms can lead to obesity, fatty liver disease, and other health problems in geckos. However, mealworms do offer some benefits: they are high in calcium (especially if you gut-load them) and they are very easy to keep alive in the fridge. To make mealworms healthier, you should gut-load them for 24 hours before feeding. That means feeding the mealworms nutritious foods like carrots, sweet potatoes, or a commercial gut-load diet. Then, dust them with a calcium powder (without D3 if your gecko gets UVB, or with D3 if it does not) before offering them to your gecko. For a complete diet plan, check out our guide on the best leopard gecko food to see how mealworms fit into a balanced rotation.

Fun Fact

Mealworms are actually the larval stage of the darkling beetle. If you leave a few uneaten mealworms in your gecko’s tank, they may pupate and turn into beetles. Some geckos will eat the beetles too, but they are even harder to digest, so it is best to remove any that transform.

How Often Should You Feed Mealworms?

For adult leopard geckos, mealworms should make up no more than 20 to 30 percent of the total diet. A good rule of thumb is to offer mealworms once or twice a week, and feed crickets, dubia roaches, or black soldier fly larvae on the other days. For baby and juvenile geckos, it is better to stick with softer, smaller insects like small crickets or phoenix worms because their digestive systems are more delicate. If you do feed mealworms to a young gecko, choose only freshly shed, soft mealworms (they look white and soft right after molting). Portion size matters too: offer 4 to 6 mealworms per feeding for an adult gecko, and remove any uneaten worms after 15 minutes to prevent them from burrowing into the substrate or biting your gecko.

Which Geckos Should Avoid Mealworms?

Not all geckos are built for mealworms. Crested geckos, for example, are frugivores and insectivores, but their digestive systems are better suited to soft, squishy insects. Mealworms can be too hard for them, and the high fat content is not ideal for a species that naturally eats fruit and nectar. If you have a crested gecko, stick to mashed fruit diets and occasional soft insects like waxworms or small roaches. Day geckos and smaller species like house geckos should also avoid mealworms because of the impaction risk. For leopard geckos, the risk is lower but still present, especially if your gecko is housed on loose sand. Using a proper terrarium sand that is calcium-based or a non-loose substrate can help prevent accidental ingestion. Always watch your gecko while it eats to make sure it is chewing properly and not swallowing the worm whole.

“Mealworms are a treat, not a staple. Think of them like a burger and fries for your gecko: fine once in a while, but not every day.”

How to Prepare Mealworms for Feeding

Preparation is key to making mealworms a safe and nutritious snack. Here are the steps you should follow:

  • Gut-load: Feed the mealworms a nutritious diet for 24 to 48 hours before offering them to your gecko. Good options include carrots, leafy greens, oats, and commercial gut-load formulas.
  • Dust: Place the mealworms in a small bag or container with calcium powder and shake gently. You can also use a multivitamin powder once a week.
  • Choose the right size: Mealworms come in small, medium, and large. For a leopard gecko, medium is usually best. For baby geckos, use small or even pinhead mealworms.
  • Serve in a dish: Use a smooth-sided dish so the mealworms cannot climb out. This keeps them contained and prevents them from escaping into the tank.

Temperature also plays a role in your gecko’s digestion. Geckos need a warm side of the tank to properly digest their food. A small reptile heat lamp can help maintain a proper temperature gradient, ensuring your gecko can digest those mealworms efficiently.

Can Mealworms Cause Impaction?

Impaction is a serious risk when feeding mealworms, especially if your gecko is dehydrated, kept on loose substrate, or eats too many at once. The tough exoskeleton of a mealworm does not break down easily, and if your gecko is not warm enough or does not have enough water, the undigested shells can build up and block the digestive tract. Signs of impaction include a lack of appetite, lethargy, and not pooping for several days. To prevent impaction, always provide a shallow water dish, keep the warm side of the tank between 88 and 92 degrees Fahrenheit, and avoid feeding mealworms to geckos that are sick or recovering from illness. If you suspect your gecko is impacted, stop feeding mealworms immediately and consult a reptile veterinarian. Gentle belly massages and warm soaks can sometimes help, but a vet should always be your first call for health concerns.

Important Tip

Never feed your gecko dead or dried mealworms. They lose most of their moisture and nutritional value, and they can be harder to digest. Always use live, wriggling mealworms to encourage natural hunting behavior and ensure freshness.