Learning to recognize protein on a product label can save you lots of time and frustration. I'll admit that I've bought a product or two that I thought was moisturizing only to find my hair dry and breaking a month later. Now that I can recognize protein in products and the level of the protein's strength, I no longer have this problem.
Products that contain protein will usually have the word "hydrolyzed" followed by a number of things. Usually the word hydrolyzed is all you need, but here are some examples.
Light, Medium, Heavy
You can determine how heavy or light a protein product is by looking at where your protein ingredients are on the label. If the protein ingredients are close to the end of the list or dead last, your product is a light protein. If the ingredient is in the middle somewhere it is medium. If the ingredients are at the top, within the first 5 ingredients, it is a heavy protein.
When to use these proteins
Light/ Medium proteins can be used up to once a week, but heavy proteins should be limited to once a month. Always follow protein treatments with a moisturizing treatment or you will be breakage city.