Nutritional Information for Reptiles
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There are many different opinions about what is right and wrong to feed your reptile. Many studies will show certain foods are too high in some nutritional areas and lacking in others. In addition, there are always new studies coming out which change the way we view nutritional requirements. 
It is not possible to duplicate a natural diet for captive reptiles. For some species, we don't even know what they prefer in the wild. For others, the food items may not be available to pet owners or readily obtainable. Even if we know what they eat and can find it, we still can't duplicate a natural diet. For example, if a gecko only eats crickets in the wild, the crickets found in the wild are eating all kinds of stuff giving them different gut nutrients than crickets in a pet store that might be fed only carrots or even gut load. Likewise, mice and rodents in the wild don't eat the same seed mix or lab block every day. They are foragers and eating an infinite amount of items we could never duplicate. 
We will not attempt to debate the details of what is the best and worst diets, which foods you should feed over others, nor are we going to offer you the perfect diet for your pet. The best advice we can offer, and we urge you to take for the health of your pet, is to always vary the diet as much as possible.  Never, ever feed only 1 or 2 items all the time, even if you alternate them. 

What we will provide is nutritional information and data about acceptable food items and commonly sold vitamin and mineral supplements to offer reptiles, and allow you to compare and decide what might be the best diet and supplements for your reptile's balanced nutrition.

In addition, to assist reptile owners who just don't have time to do a whole lot of research into nutritional requirements and diet, here is what we feed our reptiles:

Herbivore and omnivore salad

We select at least 2-3 different types of greens from the Lettuce and Greens Chart and at least 1-2 items from the Vegetable Chart. Using those ingredients mix 75% greens with 25% vegetables into a salad. Every other feeding, mix in 1 item from the either the Fruit Chart or Melon Chart.  No more than once weekly, lightly and sparingly sprinkle a small amount of a well-rounded vitamin/mineral supplement on the salad.  Pick different selections each feeding.
Many fresh greens will not keep long and salads should be fed within 24-48 hours of preparation. Do not freeze salads. Keep in refrigerator and use promptly. Use only fresh raw lettuce, greens, fruits, and vegetables. Cooking and/or freezing fruits and vegetables will often alter their nutritional content. Canned items may have additives such as sodium or preservatives. Fresh is always better.

We feed this salad to herbivores such as iguanas, tortoises, giant skinks, and uromastyx.  Some have other food requirements as well, such as grasses for certain tortoises and the addition of seed and more fruit for uromastyx.  Russian tortoises get mostly leafy greens and lettuces with little vegetables and almost no fruit, so there is some variation depending on the reptile.  There are lots of good quality food items not listed on our page that you can throw in for variety and change, or use as a special treat. Many reptiles enjoy flowers such as hibiscus, and some desert reptiles actually eat cactus.

We also offer this salad to omnivores such as bearded dragons, land turtles, some aquatic turtles, and water dragons.  Omnivores differ in the proportion of animal protein (meats) vs vegetables and fruits they need. Many will eat more insects, invertebrates, and small prey than salad. Often species will lean more towards carnivore tendencies when young and develop a taste towards a herbivore diet as they grow older, or vice versa. When in doubt, offer it all!  Keep in mind if your pet has a favorite food item, and you offer that all the time, your reptile will probably not eat other offered items. 
In many cases you will have to withhold favorite food items in order to get your pet to eat a larger variety.

Growing your own fresh fruits and vegetables for your reptiles is a great way to save some money and know exactly what your animal is getting. Be aware that if you keep your own reptile vegetable garden, you should not use chemicals, pesticides and fertilizers.  Avoid plants which are toxic to reptiles.

A list of TOXIC PLANTS to reptiles can be found here:



Insectivores are easier to feed than herbivores and omnivores, as extensive shopping and preparation is not required. Most will eat a variety of insects, worms, and other invertebrates. Insectivore owners have a particular challenge in that a variety of available insects can be hard to locate. You should not be feeding crickets alone all the time. Even if you alter between crickets and mealworms, you still are not getting enough variety to provide all the nutrition an insectivore needs.  See nutritional content of commonly fed insects here.

Besides crickets and mealworms, we feed roaches, some beetles, grasshoppers, locusts, cicada, grubs, fruit flies, and earthworms among others. You can even catch insects outside around your home, although you need to be careful not to trap in an area that has been treated with pesticides and chemicals. Wax worms and other fatty larvae are offered as a treat on a limited basis, but should not be given all the time. We avoid feeding spiders, ants, mantis and other arachnids and insects that could be venomous or dangerous to a small reptile. There are always exceptions, for example some lizards only eat a specific species of ant or certain types of beetles. Never feed lightening bugs or fire flies as the chemical that causes luminescence is toxic. 

Dusting insects with vitamin and mineral supplements is especially important since insectivores are often getting a very limited diet selection and insects are somewhat nutrient deficient. Even more critical is to select the correct type of nutritional supplement based on the species you own and that animal's needs.  The Comparison of Vitamin/Mineral Supplements below, along with proper research on your part, will help you decide the appropriate product for your insectivore.  Ask your veterinarian what nutritional requirements are recommended for your pet's health.  Use caution not to overdo it with supplements, as it is very easy to go overboard. You should not be dusting insects at every single feeding. Very lightly dust insects no more than once per week. 

Don't let the name insectivore fool you. As a rule with lizards and amphibians, if it will fit between their eyes they can and will eat it. We also offer larger insectivores and omnivores pinkie mice, small fish, and other non-insect whole prey meals. The only limiting factor is physical size.

If you breed, raise, or keep your own insects for your reptile, be sure to follow the same protocol and vary the insects diet. Gut loading the insects with commercial products is fine and recommended, but is not a replacement for also offering a variety of other normal food items.  Your lizards and amphibians are only as healthy as their food.


Carnivores are the easiest reptiles to feed, as they will eat whole animals. Variety is still important with carnivores, although many will not accept anything other than their preferred favorite prey.  You don't know if you don't try.
We feed snakes whole rodents such as mice, rats, hamsters, and gerbils. Some prefer small birds such as finch, quail, chicks, and doves; others want fish or invertebrates. Some snakes will even eat other reptiles and have a taste for lizards, snakes, and/or amphibians. A few primarily eat eggs.  Larger snakes can be offered everything from guinea pigs, rabbits, and chickens to small pigs and goats. We offer all of the above and more to our snakes.

Whole, unaltered, quality prey food should be free of chemicals, drugs, and parasites.  A rat that died from D-con rat poison will kill your snake.  We do not recommend commercial alternatives to whole prey for snakes.

In nature, all snakes find live food to consume. Snakes are not scavengers and do not eat animals that are already dead. This is why many owners will have difficulty getting snakes to accept pre-killed and/or frozen-thawed food items. Many snakes have heat sensors and can detect the body warmth of live prey. All snakes rely on visual movement to help find their food, so manually moving the food item around can help them accept it in some cases.

There are many arguments whether reptiles should be fed live food, or pre-killed. We prefer live food simply because captive reptiles are lazy and do not get much exercise or enrichment in their daily lives. Nothing perks a reptile up into high activity like chasing around food. However, there is always the chance that the prey can harm the reptile. For this reason we recommend never leaving live food items unattended in your reptile's cage. Uneaten prey should be removed and not left overnight or for any length of time. We also offer our reptiles pre-killed food occasionally, because we know some owners will not feed live and we like to know they will not starve regardless of how the new owner offers food.

One of the most common mistakes we see snake owners make is improperly judge how large of prey and how often they should feed. Species differ in how often, but as a rule younger snakes should be fed much more often than older adults. If you are not sure if your snake can handle prey larger than a mouse, or the same small rats they always get, they probably can. Snakes can safely eat a meal at least 2 times as big around as the snake in the largest part of the body. Most small mammals are little fur balls and their actual body size is smaller than appears. Many snakes can eat meals much, much larger than themselves, but too large a meal can create health issues so we don't recommend pushing the extreme limits to see how big a meal your snake can handle. If you are having to give 12 mice in a feeding to your snake, you should probably be feeding larger prey and step up to small rats.

Many other reptiles besides snakes are carnivores such as monitor lizards, crocodilians, and some turtles. Diets can differ for each species. Eggs are enjoyed by many monitor lizards on a regular basis. We feed alligators, crocodilians, and most carnivorous water turtles a diet heavy in fish and crustaceans.

Except snakes, many of these other reptile carnivores will exhibit scavenger tendencies and eat food items which are not live or whole. Crocodilians are notorious for killing live food and then stashing the carcass for a couple of days before eating. Most monitors and turtles will be more than happy to accept cuts of meats and fish.  Most of these reptiles should not be given food items larger than they can easily fit in their mouth.
If you feed your reptile carnivore grocery store or kitchen cuts of meat and fish, be sure you offer it fresh and raw and do not cook.  In addition to live fish and prey, we also at times give fish filets, shrimp, and select cuts of chicken and beef to alligators, monitors, and turtles, but we avoid pork products. Never give any meats that have been marinated, seasoned, or flavored in any way. You should only feed what your reptile will eat in one sitting and remove any raw meats from the cage immediately after feeding to avoid contamination. Some species of reptiles will take meats and fish, others will only eat whole prey animals. 

 See the  nutritional content of commonly fed prey and meat here

Some reptiles such as snapping turtles that readily enjoy meals with a little more age on them can save you money.  Meat and fish aisle clearances and manager specials at your local grocery store are the place to be for these species. 

Crocodilians that want to hang on to their meal for a while have it taken away if they don't eat right away, so we condition them to not leave rotting food for later. Eat it or lose it. 

For monitors and tegus that eat eggs on a regular basis, this is the only time that we will cook food before we offer it. Usually these lizards will break open eggs when eating, and raw egg left in the cage creates a contamination hazard. In addition, eating raw egg makes their stools absolutely unbearable. We scramble the egg white and yolk together and lightly cook until not as runny, but not yet fully cooked. We do not add anything to the egg and do not use oils, butter, or grease. When finished the egg is allowed to cool to room temperature before being offered.  We do not cook eggs for snakes that eat them as they typically swallow the egg whole.

As a rule, we don't use Vitamin and Mineral Supplements with carnivores. If you are feeding whole prey animals and rotating what you offer, carnivores should not need any nutritional supplements.

Nutritional Supplements

If there ever was a headache in providing proper care for your reptile, it's trying to figure out what kind of supplement you should use. There seems to be a never-ending line of new products containing vitamins, calcium, some with vitamin D3, some without, calcium with no D3 but phosphorous, and then of course phosphorous-free products... you get the idea. To make matters worse, a lot of the product packaging looks very similar. Compounding the problem even further, many of these companies do not provide any nutritional analysis on the label at all, and those that do use varying measurements and units making it difficult to determine what you are actually getting. And the icing on the cake... no one really knows what any of these reptiles actually needs regarding dietary and nutritional requirements.

One thing we noticed in our research is that almost every pet product retailer and manufacturer has an entire section of their website dedicated to nutritional supplements.  In other words, this is big money.  Big money means companies will sell just about anything, and not all companies are forthcoming about what they are selling.  Sometimes they will tell you that you need things you don't... because you will buy it. Sometimes what they say is in the bottle is not what you get out.

Not all supplements and companies are bad, and while we don't know exactly what nutritional requirements a given species might need, it is obvious vitamin and mineral supplementation is necessary in many cases due to the limited diets in captivity

We cannot tell you what a good product is for your pet.  Nutritional requirements of species varies greatly, and requirements differ for young reptiles than for geriatric animals. Likewise, diet and health conditions can greatly affect the proper supplementation you will need for your particular animal. We can help you make sense of what is in the supplements that are available on the market, but it is up to you to do your homework and research on your specific pet's needs. We highly recommend you consult your veterinarian before selecting a nutritional vitamin or mineral supplement for your pet reptile.

There are many conflicting reports about vitamin D3 and phosphorous in dietary supplements. To maintain a specific Calcium:Phosphorous ratio, check your diet in the nutrition charts above to see how much you are getting depending on what you feed to determine what still needs to be added to get your pet where you want be.  You will find a lot of information out there about your particular reptile's needs. Some of it is good and a lot of it is bad. There are differing opinions about proper Calcium:Phosphorous ratios, and how much if any should be supplemented, in what proportion, and how often. Likewise, there is a lot of debate about whether reptiles can even process Vitamin D3 taken orally as many reptiles process it internally via direct UV light from the sun. Not supplementing a deficient diet leads to vitamin and mineral deficiencies and metabolic problems. Over supplementing with the wrong vitamins and minerals can lead to things like hypervitaminosis, hypercalcemia, and metabolic problems. So tread carefully, read a lot of information, and try to make a good informed decision. And consult your vet!

Our word of caution is be careful not to overdo the supplements. Serious health issues can result from an imbalance of vitamins and minerals, including death, and improper use of these products can make that happen. In a perfect world, our pets would get everything they need in a good diet and not require anything additional.  If you have absolutely no idea what is the correct kind of supplement to give your pet, it is probably better to not give any of these supplements than to give the wrong one. Again, ASK YOUR VET FIRST.  Do not blindly grab any product off the store shelf and assume it is OK for your animal.  We can't provide all these answers as we don't know and are just as confused as everyone else. We try to feed a well balanced, nutritious diet to begin with and go less on the supplementation.

What we have done for you is compile a comparison chart of common reptile supplements for you to be able to compare products and their guaranteed nutritional analysis on an even level.  Some manufacturers report only a guaranteed analysis in a percentage, others provided measurements in units per kilogram, a few did not even provide units of measurement, and yet others gave figures in units per pound. Many manufacturers do not list any ingredients or give any nutritional analysis at all.

Often manufacturers gave only a minimum, or a maximum, and sometimes a range. Problem is, if a product has a guaranteed 30% calcium minimum, does that mean our lizard might be getting 75% calcium? Likewise, a 30% calcium maximum on the label does not mean the reptile is getting 30% calcium. It might only be getting 10%. Unfortunately there is no FDA for pet products, and quite simply manufacturers can list anything they want on the label, even if not accurate, without repurcussions. While the label might say the product has phosphorous, it could have little or none at all. A product that supposedly has a 2:1 Calcium:phosphorous ratio might actually have 5:2. There is simply no way to know, and no standards in place to ensure even distribution of vitamins and minerals in a given product.

Many companies also change packaging, product names, and formula often, adding to the confusion between products.  An example is we found an online national pet chain currently selling a product called Exo-Terra "Calcimize" but we could not find the same product on Exo-Terra's website.  Another example is that we have numerous multiple containers of the same supplements but with different colors on the label, different names, new formulas, etc.  Some companies don't even disclose what they are selling or what is in the product.  We tried to identify the ingredients and nutritional analysis of two different vitamin supplements manufactured by Four Paws. Neither bottle has any ingredients, any nutritional content or data, and their website does not even have a link to any reptile products, only dog and cat. Who knows what is in those bottles marked only "Reptile Vitamins"?  Likewise, ESU Reptile does not seem to have a website or anywhere customers can find information about their products.  Several products from a number of companies are nothing more than crushed sea shells, or pure calcium carbonate. That's some expensive sea shells.

None of this is helpful to the pet owner trying to determine what is in there and what their pet is getting.  We hope our chart helps with this by comparing some of these products on an even ground.  We only compared vitamin and mineral powder supplements and did not look at vitamin sprays (mostly water), gut load, recovery formula, or flavor enhancers.  Besides converting all the manufacturer's values to the same units for comparison, we also reduced the analysis to the gram level. Manufacturers often provide this data in units per pound or units per kilogram. Since we don't give our reptiles a pound of supplement, this doesn't really do any good. We used a gram as this seemed to be a common recommended dosage by the manufacturers, although we feel ONE GRAM OF MOST OF THESE POWDERS IS WAY TOO MUCH at any one time for small reptiles.  Be advised that Arrowhead Reptile Rescue is not promoting nor discouraging your purchase or use of any particular product or company. You can see the  comparison chart of nutritional analysis of common reptile supplements here showing data for 1 gram of supplement.  We also provided a download to the raw data before conversions for those who would like to see the label information as is from the manufacturer.

So now that you can compare the actual contents of these products in a meaningful way, let's look at exactly who is making some of these products. Some companies go to great lengths to hide who they really are. Others provide little or no details to the public about their operations or research. Many of the manufacturers claim to have completed vast reptile nutritional studies, years of research, with scores of scientists working on it. Some may have. However, we did not find any manufacturers website that actually had published any research studies or data in support. In fact, we were unable to find any information on any of these products outside of what was provided as a nutritional analysis on the label or the company website.   In the best interest of knowing who is making your reptile's supplements, and who their parent companies are, here is what we found:

Internet records show Rep-Cal is located in San Jose, CA. The company was founded in 1988 as the Orup Company.   They manufacture and sell a number of reptile items.

Another reptile only company, T-Rex, appears to be a small company started in Crawfordsville, IN, located in Chula Vista, CA in 1997.   

Focused on reptiles but also selling other pet products is Zoo Med, which started as a small company in Costa Mesa, CA 1984

Sticky Tongue Farms is a small family owned business started in 1992 located in Sun City, CA.  They also specialize in reptile products.

Jurassipet is a subsidiary of Seachem laboratories, founded in the 1980's with focus on marine and aquarium fish products.

Fluker Farms started in 1953 providing crickets and insects.    After marketing gut load for insects for many years, they have expanded out into the reptile nutrition market with several products.

A popular reptile name, Exo-Terra is a subsidiary of global pet products manufacturer Hagen founded in Montreal Canada, 1955,

Mostly a world-wide supplier of fish products, Tetra Fish began in Germany in 1950 and makes a number of reptile products including
the most popular turtle stick diet.

Another giant pet product company is the makers of Wardley fish and reptile products, Hartz Mountain Industries, around since 1932. 
Not as well known in name but equally large is Central Garden & Pets , owners of not only brands like kaytee, zodiac, and oceanic, but also Zilla and ESU Reptile

So how did we pick the supplements to include? 

Simple. Over 20 years these are the products reptile owners have handed over to us that they used for their reptile pets, or ones that we hear recommended the most. Also, these are the ones we could readily find data and information for. Several products were to be included but were removed from the chart because we could not find any information at all on the product label or the manufacturer's website, such as the Four Paws products we looked at. On numerous bottles of Fluker's products, ESU reptile supplements, and Bone Aid there was very little information on labels but we used what was provided. For many products, like Jurassical, we had to go to the manufacturer's website to find a little information.

So how did we get all these numbers on the same unit scale and down to one gram? 


(Caution: this will make your head hurt).  

Assuming the data and analysis given by the manufacturers is accurate, and all product containers will have the same amount of ingrediants and nutritional analysis and it is uniform throughout the container, here is how we compiled our comparison chart:

We listed the percentages given by most manufacturers, but also converted them to grams per kilogram for ease of comparison. We multiplied the given percentage by 10 using the formula 1% = 10g/kg to convert the percentage to grams per kilogram. We then multiplied by 1000 to further reduce the weights to milligrams using 1000 mg = 1 g.

Manufacturers that provided units per pound, we converted to units per kilogram by multiplying the given figures by 2.205 using the formula 1kg = 2.205 lb.

Other confusing units given on many products was ppm, which is equivilant to and we converted as 1mg/kg. We also saw both g and gm being used for gram. µg and mcg were used on different labels and products, and even sometimes on the same label for different ingrediants, even though they mean the same thing- µg and mcg are both micrograms.

Finally there is the allusive IU, or international unit, which cannot be converted to other units as IU is a vitamin or mineral specific measurement. We used the provided IU per kg provided, or converted IU per lb to IU per kg by multiplying the given value by 2.205.

After all the above conversions were made, we then further reduced the entire chart from units per kilogram to units per gram by dividing all by 1000, or 1000g = 1kg. After all, who is giving their reptile a pound or kilogram of supplement? You really want to know what you are dishing out per serving. We used one gram as that seemed to be a common recommendation on labels and instructions to give per feeding. Pictured here is exactly one gram of a reptile vitamin-mineral supplement (we tared the quarter) to give you an idea the amount we are using in this chart as a nutritional analysis.  For many products this would be too much to give your small pet reptile at one time but gives you a much more realistic idea of what you are giving your pet.  We also provided a per-tablet analysis of a commmon human multivitamin for comparison to the reptile products being sold.

 See the nutritional analysis of common reptile supplements here

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