Keratin shampoo can be beneficial, especially for damaged, frizzy, or chemically treated hair. It helps to smooth the hair cuticle, reduce frizz, and add shine by replenishing lost keratin protein.

Keratin shampoo contains added keratin proteins and amino acids designed to reinforce the hair shaft. Regular shampoo primarily focuses on cleansing the hair and scalp without providing targeted protein repair.

Frequency depends on your hair type and oil production, but typically washing 2-3 times per week is sufficient. Overuse can lead to protein buildup, making hair feel stiff, so adjust based on your hair's needs.

There is no single universally recognized "best" shampoo, as preferences vary greatly based on individual hair type, concerns, and desired results. Look for shampoos formulated for your specific hair needs and read reviews to find a good fit.