If you're looking to add protein to your bleached hair, you have two main options: using a protein filler before bleaching, or using a protein treatment after bleaching. Both have their advantages and disadvantages, so it's important to choose the option that's right for your hair type and needs.
Protein fillers are treatments that are applied to the hair before bleaching. They help to repair damage caused by the bleaching process and can also make the hair feel softer and smoother. However, they can also make the hair feel heavier and can be difficult to rinse out. Protein treatments are best suited for those with dry or damaged hair, as they can help to restore moisture and improve elasticity.
Protein treatments are applied after bleaching and work to repair damage caused by the bleach. They can also help to replenish lost nutrients and moisture, making the hair softer, shinier and more manageable. However, protein treatments can be expensive and time-consuming, so they're not always practical for those on a budget or with busy schedules.