
What is Gut Loading?
Gut loading is the phrase used to describe the pattern of allowing insects to gorge on nutritionally varied foods shortly before using the insects as prey for larger pets. Insects that are commercially available as feeders are not sufficiently nutrient-balanced to promote health for insectivorous pets. Feeder insects are particularly deficient in calcium, which is a vital mineral for reptiles that are kept as pets. They are also generally deficient in vitamins D3, A, E, and B1. Gut loading allows the insects to carry the nutrients from the food they ate in their digestive tracts. Those nutrients will be absorbed by your insectivorous pets when they consume the feeder insects.
How does gut loading insects benefit my reptile?

Most research about gut loading has concerned the calcium content in feeder insects. It has shown that gut-loading diets that are between 4% and 9% in calcium are high enough to increase available calcium present in the feeder insect. Gut loading is suitable for almost all nutrients needed by your pets. The feeder insects must have regular diets that promote the health of the feeder insects. The standard diet is not gut loading. Gut loading mimics the presence of nutrients that would be present in the digestive tract from the variety of plants that wild insects eat. This variety should include dark, leafy greens; fruits; squash; and grain materials. Tropical fish flakes are also full of protein and nutrition for a gut load. Cat food, prepared reptile foods, and bee pollen can also be used. Allow insects to fully gorge themselves when gut-loading.
Research varies on what are the optimal gut-loading times and duration. The general consensus is that feeder insects should be allowed to gut load between 24 and 72 hours before using the feeder insect as a meal. You can determine a more specific time frame by making sure to feed the insects to your reptile before the insect can pass the waste from the gut loading meal. If you keep insects readily on hand and have to feed them a regular diet, you should have some idea of the window of time to operate within. The insect should be allowed to feed for 24 hours in total.
What is dusting?
While you should provide the insects with various foods to munch on, gut loading may be insufficient for balancing required nutrients. Vitamin and mineral supplements are sold in powder form to “dust” the insects. It is quite literally covering the insect with the powder or nutritional flakes and immediately feeding it to your pet. This dusting prevents any nutrient deficiency in your pet. Your veterinarian can give you specific information about your pet’s nutritional needs, including what food you will need to gut load the insects and what type of insects work best for your reptile’s needs.
Another important factor to take into account is the palatability of the gut-loading material. If the insects do not eat it, they will not pick up the nutrients for your pet. In addition, different species of feeder insects absorb different nutrients at different rates. For example, field crickets absorb more carotenoids than banded crickets. Carotenoids are a nutrient found in carrots, other vegetables, and certain fruits. Commercial gut-loading diets are high in calcium to make up for the insect’s natural lack of calcium. Such diets should only be used for gut loading and not for the insect’s general diet, as they are generally high enough in the needed supplements. Still, they can be expensive, and insects do just as well when gorging and feeding on fresh produce. However, they are usually very convenient, with easy-to-follow instructions about how to gorge the feeder insects with the product.
What should feeder insects eat?
Remember that the primary diet of feeder insects affects their nutritional content in addition to gut loading. If you keep insects readily on hand, you will have to feed them to keep them alive, as well as feeding that final gut load. Their primary diet will also give you an idea of the foods they may avoid, so you will know not to include such foods in the gut load meal. Most insects can be fed with a commercial diet or a mixture of leafy greens and brightly colored fruits and vegetables.
Suitable green vegetables for the gut load include:
- Collard greens
- Kale
- Mustard greens
- Romaine lettuce
Brightly colored plants to gut load your feeders include:
- Carrots
- Oranges
- Potatoes
- Apples
- Squash
- Sweet potatoes
You can also feed the insects grain. Acceptable grains can include:
- Baby rice cereal
- Wheat germ
- Alfalfa
Insects must stay hydrated, so allow them to consume fresh produce, hydration gels, or fresh water. Oranges are recommended for their ability to promote hydration in feeder insects. Insects drown easily, so ensure there are easy escape routes from a water container, and change the water regularly to prevent bacterial build-up. Insects fed a commercial, high-calcium gut load diet may stop eating fresh produce and must be provided with water for hydration. Even with all this variation, it remains possible that a gut load may be insufficient in certain vitamins or minerals. Dusting the insects with calcium and multi-vitamin powders serves to cover any final potential insufficiencies.
It should be noted that the nutritional content delivered by dusting can be difficult to measure. Some of the powder is rubbed off by the insects’ grooming before your reptile feeds. Alternatively, you can sprinkle the gut load food with the reptile multi-vitamin powders so that the powders sit in the insect’s digestive tract.
What are the types of gut loading food?

Gut load food comes under two categories: dry and wet. Wet food is anything that contains moisture and will help keep the feeder insects hydrated. Most commercial nutrient mixes are dry rather than wet. Water gels pair well with fresh vegetables to maintain good nutrition and hydration. Hydration is just as important to the health component of the feeder insect as the gut load material. Offering dehydrated prey to a reptile can wind up dehydrating your reptile. Most reptiles will need high amounts of calcium, so be sure and allow the insects to feed on high calcium options.
Examples of this include:
- Acorn squash
- Butternut squash
- Sweet potatoes
- Collard greens
- Mustard greens
- Kale
Avoid spinach, as it contains oxalate, which binds with calcium and makes it unable to be synthesized by your reptile. If you vary the gut load between groups of feeder insects, then your reptile will maintain a healthy and varied diet. Check with your veterinarian or research thoroughly before trying new foods for gut loading. Providing a good diet and hydration will help keep feeder insects alive until you need them as prey.
Finally, there are potential pitfalls concerning gut loading. Certain studies have shown that commercially available dry gut load diets are inconsistent with the amounts of calcium they display on the label. Therefore, dusting should be considered. They also contain particle sizes that are too large for insects to eat, defeating the purpose of the gut load. It is vital to quickly feed the insect to your pet after the insects have gut loaded before they expel the nutrients they cannot digest.
If you have any questions and want to learn more about gut loading to keep your reptile healthy, contact Allan’s Pet Center today.