Because of the added goodies in the Holistic Horizons program...an increase in cleansing reactions may be experienced. I usually have a bit more discomfort in terms of temporary headaches, muscle tension and fatigue when using these products...which almost always passes when I have the next bowel movement. I don't want to scare anyone here...these reactions are considerably less than with some of the other more aggressive cleanses...but I did want you to know that this can happen. Without a doubt...it is worth it!