Reptile Nutrition Guide

Best Feeder Insects for Bearded Dragons: Dubia vs Crickets vs Mealworms & More

Updated July 31, 2026

The short answer: Dubia roaches and black soldier fly larvae (BSFL) are the best staple feeders for most lizards. Crickets work well but are noisy, smelly and short-lived. Mealworms, superworms and waxworms are treats, not staples. Always gut-load feeders for 24 hours before offering and dust with calcium with D3.

Why insect nutrition matters

Your lizard is literally made out of what its prey has eaten. Two insects of the same species can have wildly different nutrition depending on how they were raised and what they ate in the last 24 hours. Three numbers matter:

Protein — higher is better for growing dragons
Fat — too much = obesity; some fat is fine
Calcium-to-phosphorus ratio (Ca:P) — should be at least 1:1, ideally higher. Phosphorus blocks calcium absorption.
Chitin — hard exoskeleton; too much causes impaction, especially in juveniles

📊 Feeder insect comparison

Insect	Protein	Fat	Ca:P	Use as
Black soldier fly larvae	~17%	~9%	3:1	Staple
Dubia roaches	~23%	~7%	1:3*	Staple
Crickets	~20%	~6%	1:9*	Staple
Hornworms	~9%	~3%	1:3	Treat/hydration
Silkworms	~17%	~2%	1:2	Occasional
Superworms	~19%	~16%	1:18*	Adult treat
Mealworms	~20%	~16%	1:7*	Rare treat
Waxworms	~15%	~25%	1:7	Rare treat
Butterworms	~15%	~18%	1:2	Rare treat

* Ca:P ratio improves dramatically after proper gut-loading and dusting. BSFL are the only common feeder with naturally positive calcium balance — even without dusting.

🥇 Best staple feeders

🪳 Dubia roaches (the gold standard)

High protein, low fat, relatively quiet, long-lived (2 years), easy to keep in a bin, no odor when kept clean. Their soft body makes them easier to digest than mealworms. They cannot climb smooth surfaces or fly (males have wings but don't fly), so they don't escape easily. The only downsides: slightly higher up-front cost and they need warmth (75-90°F) to breed.

Verdict: best staple for most keepers. Buy in bulk to save money.

🪰 Black soldier fly larvae (BSFL / "Phoenix worms" / "calci-worms")

The only common feeder with a naturally positive Ca:P ratio (3:1). Extremely high calcium means you don't even need to dust them with calcium. Lower protein than roaches but excellent nutrition. They don't need feeding/gut-loading. Short shelf life (1-2 weeks). Best served in a shallow dish so they don't escape.

Verdict: excellent staple, especially for baby dragons and breeding females needing extra calcium.

🦗 Crickets

Cheap, widely available, great exercise for dragons (they move fast and trigger hunting behavior). But they smell bad, chirp loudly, die quickly in large numbers, will nibble on your dragon if not eaten, and can carry parasites if from poor sources. Gut-load very well — their natural Ca:P is poor.

Verdict: fine staple if you can tolerate the smell/noise. Buy from a clean supplier, never wild-caught.

🍬 Treats (not staples)

Hornworms (hydration/weight gain)

Big, bright green, juicy — dragons go crazy for them. 85% water, so perfect for dehydrated or underweight dragons, or as a rare treat. Low nutrition otherwise. They grow FAST (to 3-4 inches) so order small and feed them off quickly.

Superworms (adults only)

Big, wiggly, popular with adults. High fat and a hard head — never feed to juveniles (impaction risk). Best as a 1-2x/week treat for adult dragons only. Don't refrigerate (kills them).

Mealworms (rare treat)

Cheap, easy to keep, but very high in hard chitin. They cause impaction in juvenile dragons — that's a vet bill and possibly fatal. If you use them, limit to adults, 1-2 per meal, and choose freshly-molted (white) ones when possible.

Waxworms (the candy of the bug world)

25% fat — essentially reptile potato chips. Dragons get addicted and refuse healthier food. Reserve for an occasional treat, or to entice a sick/brumating dragon to eat.

🚫 Insects to never feed

Wild-caught insects — carry parasites, pesticides, herbicides. One firefly kills a dragon instantly.
Fireflies / lightning bugs / any glowing bug — EXTREMELY toxic to reptiles, even one kills.
House flies, ants, bees, wasps — stinging/venomous or nutritionally poor.
Butterworms for juveniles — tough exoskeleton.
Any bug you can't positively identify.

🥬 Gut-loading and dusting

Even the best insect is only as good as what it ate last. Gut-load means feeding nutritious food to the insects for 24-48 hours before offering them to your dragon.

Feed insects collard greens, dandelion, squash, sweet potato, or a commercial gut-load formula
Provide moisture via water gel cubes or fresh veggies (don't let them drown in open water)
Dust with calcium WITH D3 at most feedings (toss insects in a bag with powder)
Multivitamin 1-2x per week (replaces calcium that feeding)
BSFL don't need calcium dusting due to their natural calcium

📏 The size rule

No matter which insect you choose: never feed anything longer than the space between your dragon's eyes. Too-large feeders cause impaction, paralysis and death. Size guide:

Dragon age	Insect size
Hatchling (0-2 mo)	Pinhead crickets, fruit flies, tiny BSFL
Baby (2-6 mo)	¼ inch crickets, small dubia, BSFL
Juvenile (6-12 mo)	½ inch insects, medium dubia
Subadult (12-18 mo)	¾ inch, large dubia, small superworms
Adult (18+ mo)	Adult insects (insects only 20% of diet)