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The highly debated topic of iguana diets. With the increased popularity of pet iguanas and the fact that there is still much to be learned about them, diets as well as many other aspects will constantly be debated and discussed. Instead of providing a specific diet or listings of foods that must be fed, the Green Iguana Society would like to provide listings of foods that may be fed, foods that have been known to be dangerous, and leave it up to the iguana owner to decide which foods should be fed. We realize every iguana is different and every iguana owner is just as different, so instead of continuing a debate on diets, we would like to state that these are only our recommendations of foods that can be chosen as a part of a complete and healthy diet. Basically, we want to provide as many facts that are known about certain foods and methods, and hope that each person will plan their own iguana diet based on the information we provide.

Iguanas are strict herbivores.Although many iguana care books and a few people still recommend iguanas be fed insects and other animal protein based foods, the Green Iguana Society would like to stress that iguanas are strict herbivores (plant eating only). The myth that iguanas in the wild have been seen eating insects can be explained in a number of ways, but the fact is that they usually only eat insects in the wild by accident along with a piece of vegetable matter or by necessity when no other foods are available. Since iguana owners have complete control of their pet's diet, the Green Iguana Society recommends that insects and other foods containing animal protein should be avoided as much as possible, if not completely. For more information on animal protein, including various views on the subject, make sure you visit our Animal Protein Issues page.

How iguanas eat and drink.Iguanas have many small teeth which they rip and tear their food with, instead of chewing it. Usually, they will take large bites and swallow their food whole and occassionally they will just tongue-flick their food into their mouths. When they drink water, which is usually only occasionally, they will dip a large portion of their head into the water, lapping up the water under the surface or sometimes they may even lick water droplets off of plants and other misted surfaces.

The importance of providing fresh food and water. Obviously, the most important thing needed in the caring for a green iguana is providing fresh food and water. Fresh water should always be available and when feeding, only fresh food should be provided. Dirty water and/or spoiled food can lead to serious health problems, as well as provide a very unsanitary environment.

How often should an iguana be fed? Feeding an iguana daily is recommended. Many books and people recommend feeding an adult iguana every other day or every few days, but the Green Iguana Society definitely recommends that all iguanas should be fed every single day. One meal, two meals, three meals or more is fine, just as long as it’s every single day and that the iguana is being fed enough to stay healthy.

How much should an iguana be fed? Depending on the size and age of the iguana, appetites will vary. An iguana can not be overfed. Basically, it’s a good idea to feed it until it won’t eat anymore. The owner will be able to tell how much food is enough after spending some time with it, getting to know how and how much it eats. If the iguana has eaten and it’s apparent that it is done for that sitting, it’s a good idea to remove any uneaten food as soon as possible, to assure that it won’t eat any spoiled or rotten food and to maintain a clean area for it to live in. This will also help keep it on a regular feeding schedule.

What times should an iguana be fed? Usually, it’s a good idea to feed an iguana early in the morning. A half an hour to an hour after it's awake is a good time. Providing food in the morning allows it to properly digest its food with the aid of proper daytime temperatures. Feeding more food later in the day is fine, but it's generally not a good idea to feed an iguana the bulk of its daily food before it goes to sleep. It can also be a good practice to feed at the same times every day. An iguana that is in a routine of eating at the same time every day will also be in the routine of defecating at the same time as well. This can be important in order to establish good litter box or even toilet training. For more on litter box and toilet training, see our Taming & Training page.

Food and water bowls. Food should be provided in a shallow bowl of some type. Bowls or dishes that are made of ceramic, glass or plastic, if cleaned regularly, will work perfectly. Iguanas tend to dig at their food and sometimes walk or climb into the bowl. Using a bowl that will not be easily tipped over is a necessity. It can also be a good idea to use disposable food dishes. Disposable shallow dishes can be found at various stores and can be affordable and extremely clean as well. When providing food and water, it's very important to consider the importance of where the food and water will be in the habitat. The food bowls should be placed in an area away from the bottom of the habitat (if possible), to prevent any problems with accidentally eating any substrate material as well as keeping it away from any fecal matter, which may lead to various health problems. Water bowls are best utilized when more than one is provided. Water bowls placed in the bottom of the habitat can and usually will be used as a place to defecate. If this happens on a regular basis (whether intentional or not), it's very imporant to provide another source of clean water. The size of the water bowls that are provided to be used as drinking water should be small enough that they will not be able to climb into the bowl.

Train your iguana to drink more water! Iguanas will usually drink water from a bowl or other container. You may not see it drink the water, but most generally it is drinking some amount of water. If you want to make sure that your iguana is drinking plenty of water, you can also train your iguana to drink more. A good way of training your iguana to do this is by placing a treat or other piece of food in its drinking bowl each day. A large piece of collard or mustard greens or other food that your iguana likes should work fine. When your iguana eats the treat, it will most definitely take in a lot of water and hopefully have a drink of it. If your iguana takes to eating the treat, gradually reduce the size of the treat every day for a few weeks to even a few months. The more time you spend training it to drink the water, the more likely it will keep up the good habit of drinking lots of water. By the end of the training period, you should simply be offering a fresh bowl of water to your iguana each day. Even if you see your iguana drink water, training it to drink as much as possible each day can help your iguana stay healthy and is highly recommended.

Spraying food with water. Another very good way of making sure your iguana is getting plenty of water in its diet is by spraying its food with water. This can be done by simply spraying water on the food with a spray bottle. Spraying the food with water can be done on a regular basis or just in times when you think its not getting enough water with the types of food you're providing in that particular feeding. Once again, make sure you remove any uneaten food as soon as possible, to assure that it won't eat any spoiled or rotten food.

Importance of proper temperature. No matter how good the diet is, if the proper temperatures in the habitat are not reached, the iguana will not fully digest the food it eats. After the iguana eats, temperatures of at least 85 are needed to properly digest the food. For more on how to keep the proper temperatures, refer to our Habitat page.

Variety, variety, variety! Providing a wide variety of good quality foods is the key to a good diet. Iguanas in the wild are known to eat a large variety of plants and fruits, and iguanas in captivity should have the same opportunity. Besides, no one likes to eat the same foods all the time, and your pet iguana should be no different. Over time, you'll figure out its favorites and you can supply these more frequently, as long as the diet remains well balanced.

The importance of the calcium to phosphorus ratio. An iguana absolutely needs strong, healthy bones in order to stay healthy. One of the most important factors in providing a well balanced diet is maintaining a calcium to phosphorus (Ca:P) ratio of about 2 to 1. This is critical in order for the bones to properly grow and remain strong. Some foods are high in calcium and low in phosphorus, while others are low in calcium and high in phosphorus. Both types can be good additions to the diet, just as long as the total overall diet has at least a 2 to 1 calcium to phosphorus ratio. Please refer to Food Information Chart for more detailed information on the Ca:P values for various foods. One word of caution about the calcium to phosphorus ratio: Many people get so caught up in making sure the Ca:P is 2:1, they end up feeding their iguanas the same diet with very little variety in some foods that may improve the overall diet. This is just another reminder that the most important part of feeding an iguana is to provide a wide variety of the "good foods", while maintaining an overall calcium to phosphorus ratio of 2 to 1.

How sunlight and UV rays are needed to help with a proper diet. Along with proper diet and temperature, proper lighting and exposure to natural sunlight will most definitely help in utilizing the calcium provided in the iguanas diet. Iguanas produce vitamin D3 when they are exposed to proper amounts of UVB rays and vitamin D3 is needed in order for the calcium to be absorbed. This may sound a bit confusing, but as long as the proper amount of quality UVB lighting and sunlight is provided, vitamin D3 should be produced and the calcium in the diet will be fully utilized.

The good foods. The following is a table of good foods in six different catagories: greens, other vegetables, fruits, grain-based foods, supplemental proteins, and other occasional foods. Based on several other very popular diet recommendations, the Green Iguana Society's recommends the following percentages. We hope that iguana owners will develop their own diets based on the information we're providing. Once again, using a variety of these foods as the main portion of the diet, along with a variety of other vegetables on occasion and in moderation, is the key to providing a good, well-balanced, healthy diet. On occasion and in moderation means that you should only provide those foods as a small part of a meal or a group of meals, every few months. A food that is recommended only on occasion and in moderation can also be an acceptable snack or treat, but only occasionally. These are only a few of the best foods and there are many other foods that are also very good parts of a diet. For more detailed information about the foods listed here, including nutritional information and photos, make sure you look at our Food Information Chart.

Catagory of good food types

Food

Greens
(40-45%)

Collard greens, turnip greens, mustard greens, dandelion greens (with flowers), escarole, water cress.

Other vegetables
(40-45%)

Green beans, orange-fleshed squashes (butternut, Kabocha), snap or snow peas, parsnip, asparagus, okra, alfalfa (mature, not sprouts), mushrooms, bell peppers, sweet potato, zucchini, yellow squash, carrots.

Fruits
(10% or less)

Figs (raw or dried), blackberries, strawberries, raspberries, grapes, mango, melon (cantelope, honeydew, watermelon), papaya, banana, apple.

Grain-based foods
(less than 5%)

Cooked rice or pasta, whole wheat bread (makes for a great treat)

Supplemental protein
(less than 5%)

Alfalfa pellets (rabbit food) or recommended commercial diets (see below).

Other occasional foods
(less than 5%)

See below for lists of foods that should not be fed in excess, but can still be an excellent way to provide variety and fun. Mixing in other foods on occasion is recommended.

 

Oxalates and phytates. Many foods contain oxalates and phytates. It has been proven that they sometimes bind to calcium, inhibiting it from being properly used by the body. It's not a fact that this is true in iguanas, but better safe than sorry is always a good practice in iguana care. Below is a list of foods that contain oxalates or phytates and should only be fed occasionally.

Foods that contain oxalates or phytates to be fed only on occasion and in moderation.

Spinach, beets, beet greens, swiss chard, dock, sorrel, whole grains, celery stalk, kale, carrot tops.

 

Cruciferous foods and goitrogens. Many foods contain goitrogens. Goitrogens are substances that has been shown to bind iodine. This may lead to hypothyroidism. The foods that usually contain goitrogens are members of the cruciferous family of vegetables. These foods can be fed on occasion along with a balanced diet that will compensate for the effects of the goitrogens, but only occasionally and not in excess. The following is a list of cruciferous vegetables that contain goitrogens.

Cruciferous vegetables and other foods that contain goitrogens to be fed only on occasion and in moderation.

Kale, brocolli, cabbage, bok-choi, turnips, brussels sprouts, cauliflower, rutabaga, tofu.

 

Foods to avoid. There are many foods that should never be fed to an iguana. Below is a chart of various foods that should usually be avoided, although some of these foods can still be given occasionally. Many of the foods listed here contain animal protein. For more information on animal protein, make sure you read our Animal Protein Issues page. Note: Although we recommend that several of these foods should never be fed to your iguana, if your iguana happens to eat any of these foods by accident, you need not worry too much about the effects of it. We are simply saying "never" to stress the importance of how harmful these foods will be, if fed on a regular or semi-regular basis.

Foods to avoid

Information

Recommendations

Insects, worms, mice, pinky mice

Animal protein, not a natural food.

NEVER!

Dairy products (milk, cheese, cottage cheese, yogurt, etc.)

Dairy products are intended for mammals, not reptiles.

NEVER!

Eggs

Animal protein, very high in phosphorus and fat.

NEVER!

Dog food, cat food, monkey biscuits, monkey chow and other pet food

Animal protein, intended for dogs, cats and monkeys. Sometimes high in fat content.

NEVER! We do not recommend these because of the animal protein they contain. Some still recommend that they are okay on occasion, but we do not agree.

Meat (beef, chicken, etc.)

Animal protein, not a natural food, intended for carnivores...not herbivores.

NEVER!

Rhubarb

Poisonous and should never be fed to iguanas.

NEVER!

Lettuce (iceberg, romaine, Boston, butter)

Lettuces are a common staple of many malnutrioned iguanas, most lettuces (especially head lettuce) are very low in nutritional value.

Occasionally is fine, but there are many better foods to provide instead. Romaine lettuce is the better of all the lettuces, but still lacks adequate amounts of nutritional value.

Wild plants and flowers

Possibility of being contaminated with herbicides and pesticides, could be a toxic plant

Occasionally, ONLY if there is absolutely no chance of being contaminated or toxic. Very risky and not at all recommended.

Acidic foods (citrus fruits such as oranges, grapefruit, limes, kiwi fruit, lemons, pineapple; and tomatoes)

Some iguanas may not like eating acidic foods and it may be likely that the iguana can not properly break down the acid in the food, not a natural food choice.

Occasionally is fine, only if the iguana doesn't have any negative reactions to it. Some people offer these foods for more variety and color.

Tofu

Although high in plant protein, tofu is very high in fat. Also contains goitrogens.

Occasionally is fine, but in excess, can lead to serious health risks.



Where to buy food. So, now that you've decided what foods to feed your iguana, you must now figure out where to buy them. Most commercial grocery stores and markets will carry a wide selection of fresh vegetables and fruits. It's not uncommon for iguana owners to suddenly realize that there's a whole section in the store with fresh vegetables. In rural areas and small towns, getting the variety you want may be difficult. Many people who live in small towns make a weekly road trip to another town that may offer more variety. Although small town stores may lack in variety, there may be farms or farmer's markets in the area that can also be an excellent source for very fresh food. Many foods are very seasonal and can only be found in certain parts of the year, so you may have to adjust the diet during those times. If you're having trouble finding certain foods in your area, the best thing you can do is to ask people where to go. Many markets and grocery stores that don't carry all the foods you're looking for will point you in the right direction. Simply tell them that you're a regular customer and that you're looking for something in particular and most of the time, they will be very helpful.

Commercial frozen vegetables. Bags of frozen vegetables can be thawed and fed from time to time. These can serve as an excellent emergency food when the fresh food is gone, or if there is no time to go to the store or market. It's not a good idea to rely on commercial frozen foods as a regular part of the diet, but occasionally is fine. Also, remember to add crushed vitamin B1 tablets or brewer's yeast. For more information on adding supplements to food, please visit our Vitamins & Supplements page.

Eating habits & picky eaters. Some iguanas will prefer certain foods and may not want to eat other foods. Do not let your iguana train you to feed it only the foods that it wants. Mixing foods that it does not like with other foods is a good way to avoid a problem with a picky appetite, and eventually its appetite will change. Grating and chopping up the food you provide in a mixture will also help eliminate picky eating habits. Don't give up on trying to get your iguana to eat the right foods or you may end up with an iguana with a very unhealthy diet. It's not uncommon for an iguana to constantly change its taste and desire for certain foods. Allowing it to train the owner into feeding only foods it likes should be avoided.

Hand feeding. Feeding an iguana by hand can be a very good thing to help tame an iguana. It can also turn into a very bad habit. We suggest that you feed your iguana by hand from time to time, but don't do it all the time or your iguana may not want to eat any other way. Also, it's very important to be extremely cautious when feeding by hand, especially with large iguanas. Even iguanas that never attempt to bite their owners can have accidents and serious injury may result if you aren't careful and paying very close attention when hand feeding your iguana.



Wild foods and growing an iguana garden. Although it can be risky to feed wild plants and flowers to a pet iguana, it can be a very good and economical idea for iguana owners to grow their own vegetables. This can also be a very good way of absolutely knowing that the vegetables are fresh and free of any harmful substances. Planning and growing vegetables can also be another enjoyable part of iguana ownership.

A note on house plants and toxic plants. Since we are providing information on foods and feeding, we would like to mention the dangers of iguanas eating house plants that may be toxic. There are many common house plants (and even some vegetables) that can be toxic if an iguana happens to eat them. If the owner is unsure about the toxicity of plants that the iguana has access to, it is important that the iguana's access to these plants be restricted until the plants are researched by the owner and deemed safe. Visit our Toxic Plants page for a list of toxic plants.



The Iguana Pages by Jen Swofford contains her Complete Guide to Keeping Giant Green Iguanas in Captivity. This incredible guide contains a great deal of excellent information on nutrition, including diet recommendations, several charts, and just about all you need to know to properly feed an iguana. She also has in-depth charts on the nutritional content of most commonly fed foods.
Iguana Care, Feeding & Socialization by Melissa Kaplan is an excellent guide to iguana care. The entire article, as well as her entire site, is an excellent source for all iguana owners.
The House of Galahad Quick Iguana Nutrition FAQ by Catherine E. Rigby-Burdette is another excellent source for more information on iguana diets, including charts, photos, feeding recommendations, and links to other sites.
Sammy J. Eguro is a site by Marie Eguro that has a perfect example of how unique an iguana's diet can be. Her two iguanas are fed a wonderful variety of foods that she tailors to their likes and dislikes and with her recommendations, your iguana will without a doubt be provided with a fantastic variety of healthy foods.







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