Most people wonder why a keratin treatment lasts so long. The reason is based on how it is done. A hair stylist will use heat in order to connect natural keratin with that one in your hair. After this, they will use a flat iron which will make your hair long and straight. The results will last for a long time. Keratin doesn’t wash out in a few days. Your hair will look perfect more than a month. Sometimes a keratin treatment lasts 4 months. As for products, the amount that should be used also depends on hair:
Consumption: 15-20 ml
Short hair (shoulder-length): 30-40 ml
Medium length hair (shoulder blade length): 50-60 ml
Long hair (waist length and longer): 80-90 ml
Consumption: 20-30 ml.