The diet of the iguana should be milled or itched in small pieces that the iguana is able to swallow. 
A good diet is the one based on pellets, (calls think or I feed balanced in some countries) of medic soaked in water, because they are very hard and the iguanas can ingest this way them, although they are much more tempting for the iguanas if they are soaked in grape juice (the pellets is in the pets shops, and they are for the rabbits). These pellets should also be soaked in an isotonic drink as Gatorade to recover the lost salts due to the pelisse process. Fresh medic could also be given and itched in small pieces; leaves and hibiscus flowers, rose flowers, buds of non toxic plants as Moorish, etc.; fruits like melon calameño, apples, pears, grapes (without seeds), tomatoes, etc., only small orange pieces for their acidity, and small banana pieces to possess contained first floor of calcium and match; vegetables like pumpkin, carrot (not much), Italian pumkin (marrow), green dry bean (green Jews), etc.. he/she Remembers that with a varied diet, the iguana should not present nutritional deficiencies. He/she remembers, it is better NEVER to feed the iguanas with SPINACH. The flowers that you give to your iguana should not have pesticides since these they can cause toxicity in your iguana. 
It is advisable to make a diet to the iguana for about two or three days, and if you freeze it, this it should not be more than frozen 45 days. 
It is necessary to give the lukewarm food to the iguanas and never freeze, is not good to give to any animal the icy food, since it destroys the cilios of the intestine that are small "hair" that are in the surface of this. 
The iguanas don't like to eat every day the same thing, so to mine, when I eat fruits, I give them fruits; if there are other vegetables, I give them, and it is necessary this way to go varying. You/they can also be given only pellets during a couple of days. The important thing is that the diet is varied and don't eat the same thing during the whole week. 
It never owes give it products of animal origin, either insects (for small that are), eaten for dogs or it stops cats, meat, eggs, etc.. The iguanas are totally herbivore, so they should not receive foods of animal origin. In some texts I have read that it owes give it small animals regularly as earth worms and crickets as source of proteins, but the iguanas to the herbivore being, they cannot metabolize these protean foods of animal origin and they could develop important illnesses to the liver or the kidneys. Some vegetables that you/they cannot eat also exist; the acids as the orange and the lemon would make them bad in high quantities; the lettuce will only fill the iguana, this he/she will stop to be hungry but he/she won't feed, it is as the French fries, they fill but they don't feed; spinach should never be given to the iguanas, sometimes yes one can, but in very small quantities, the spinach produces serious problems in the iguanas, better not to take a risk and not to give them. The spinach produces sour oxálic that doesn't produce damage because it is not toxic, but he/she unites to the calcium of the diet and form strongly united complexes that are impossible to separate, the valuable calcium of the diet it is this way bound and unusable. Other foods with high sour oxálic are the rhubarbs, the beet and the celery. Other foods that could produce damage in the iguanas are those that cause deficiency in the gland thyroid. These are broccoli, cabbage, cauliflower and turnips. These you can give them it is small quantities and not very followed. Other foods potentially dangerous they are those that have a high tanine content, these they are spinach, carrot, banana, grape, lettuce, rhubarbs and onion, although you/they can also be given sporadically. 
The iguanas should always have food in their sump for this, it is never necessary to let that the food finishes, since the iguanas don't always eat oneself hour, and go to eat and not to find anything. Whenever they finish the plate, it fills it again. The sump with the food should be taken out and laundry together with the remains of food every day, since they are formed mushrooms with the humidity and the heat on the remains; if the iguana ingested these mushrooms, maybe I/you/he/she could cause him digestive problems. If one had more than an iguana in the same box, it is advisable to give them the food in more than a sump, to avoid possible disputes and fights for the food. It is not common that the iguanas fight to each other to take off the food, but it is also strange to see them share the trough at the same time. Generally a wait to that the other one finishes, go to eat. It is also convenient that the troughs are separate some of others. These sumps should be plane, so that the iguana can enter to this to eat, and to place the paws above her food. The best hour to feed the iguanas is in the morning, since they digest the vegetables with bacterias in its bowels and these they need heat to be able to metabolize the foods. 
The diet of the iguanas should include vitamin D, calcium and match, it stops this way to avoid an illness for bad well-known nutrition as metabolic illness of the bones (MBD). The signs of this illness are characteristic and they are swelling, muscles of the rigid thighs, sudden paralysis and limp in an or more paws. 
It dilutes 
The iguanas, the same as all the other alive beings, need of the water to be able to live. They need the water to take, so it is necessary to put a small plate with water so that they can come closer to take. Sometimes, when the diet is humid, the iguanas don't come closer to the plate to drink water, so it is not of being missed not to see them taking.