I have struggled with sleep issues and had terrible headaches due to this. Everytime I deviate from the same sleep and wake times, I have problems with headaches and other health issues. NAD everytime gets me back into the right sleep routine, and by day 2 I am tired in the evenings and more energetic during the day. I wake up by myself, feeling rested and ready to get up, something I never experienced before using NAD. Inflammation pains also much better and some symptoms are gone! Amazing product!