Wheat protein is the most widely used protein in hair care, and that comes down to a single property: it has an unusual ability to bind water. Each protein fragment can hold many times its own weight in moisture.
The fragments penetrate the hair shaft and stay there as small moisture depots. They release the water slowly over the course of the day, so hair does not dry out when the air is dry or after heat styling. They also form a light film on the surface that protects against the oxidative damage caused by sun and pollution, which otherwise leaves hair dull and brittle over time.
That combination of moisture inside and protection outside is why wheat protein feels different from an ordinary conditioner. Hair does not just become smooth, but supple and full, and the ends last longer before they start to split.
