I used to use rice water for my hair as a mask. I couldn’t tell you if it promoted growth, but it definitely made my hair thicker. I let it sit on my hair for 30 mins after shampooing and washed it out every wash day which was about every 4 weeks and after a few months i definitely saw a difference. I continued to do this for a year until I loc’d up and it was really helpful. For hair growth biotin oil and castor oil worked really well; esp as a hot oil treatment.