I went cold turkey on coffee back in December, from 3 cups a day to zero. Noticeable head-aches but tolerable. The worst thing was a couple nights where I experienced pain throughout my body when trying to sleep at night. No matter what position I tried, my body felt like it was burning. Eventually the night pains went away but man was it uncomfortable. I didn’t notice any improvement in sleep after the withdrawal symptoms wore off. Eventually I started drinking coffee again, but limited it to a single cup a day. I noticed my tolerance went way down and so drinking just a small cup made me feel like I had drank 3.