A ten day juice fast in February 2012 helped me in two ways. (A) Towards the end of the fast, I started feeling much calmer than before. The change was noticeable and significant. (B) On the fifth day, I learnt about Plant Based Diets. Upon finishing my fast, I permanently transitioned into these food habits.
Personal experience doing a 26-day water-only fast in Jan 2019.
The first time I did a 'dry fast' for 24+ hours was on 9 June 2019 (Sunday). It was unplanned — a lazy day transformed itself into a dry fasting day! :)