What is the most common cause of hair breakage?

Chemical treatments are the most common cause of hair breakage because they often involve the use of strong agents that alter the hair structure. Processes such as coloring, perming, and relaxing can weaken the protein structure of the hair, making it more susceptible to damage. These treatments can strip the hair of its natural moisture and oils, leading to increased fragility and breakage.

While environmental factors, poor nutrition, and excessive washing can contribute to hair health, they do not have as direct a relationship with breakage as chemical treatments do. Environmental factors might cause dryness or UV damage, poor nutrition can lead to overall hair health decline, and excessive washing may strip natural oils but typically do not lead to immediate structural damage like harsh chemicals can. Thus, the impact of chemical treatments on hair integrity is significant, establishing them as the leading cause of breakage.