Since we don't feed animal protein to iguanas, and plant proteins have some problems in terms of either not having enough protein or too much of some harmful plant chemical, how are we going to make sure our iguanas get enough protein?

Alfalfa!

Alfalfa is an excellent source of plant protein--just think of what it does for horses! Seriously, though, mature alfalfa is a great source of protein, fiber and calcium. Mature alfalfa is 15% protein by volume and has a 6:1 calcium-phosphorous ratio. The difference between mature alfalfa and alfalfa sprouts is that alfalfa sprouts have considerably less protein, calcium, and other nutrients and are not recommended as a primary food for herbivorous lizards.

When I first started using alfalfa in the iguana diet, there were few resources easily available. There were the pellet products sold for small mammal pet food and bedding, and small hay bales, also sold for small animal bedding. The pellets were of variable quality, with many containing animal protein, significant amounts of grains or corn, and fat. One could also find larger pellets, those made for sheep and horses, and larger bales of hay, also made for larger farm animals. Thus, the earlier version of this article recommended good quality alfalfa pellets as the source of alfalfa for the iguana diet.

In the several years, alfalfa has become more readily available, in purer forms, as it has become popular as a nutritional supplement for humans. You can now find powdered alfalfa, alfalfa tablets and capsules, and alfalfa leaf tea in health food stores and through mail order vitamin and herb suppliers. You may be able to find some sellers offering the alfalfa powder and tea in bottles, bags and in bulk so that you can buy as little or as much as you need.

Alfalfa pellets and mini-bales are still available, still sold as rabbit food or small mammal bedding at pet stores and farm/ranch supply stores. Generally speaking, however, alfalfa packaged for human consumption is likely to be a little cleaner than alfalfa packaged for animal food or bedding.