Caffeine is consumed by 9 out of 10 people and produced at over 4 million tons per year globally. While it provides instant energy, it can also negatively impact mood, behavior, and health. Caffeine is addictive and can cause withdrawal symptoms like headaches and fatigue when quitting. It is associated with increased risks of various cancers, heart disease, miscarriage, low birth weight, and calcium loss. Reducing or quitting caffeine intake requires willpower but symptoms subside after a few days with strategies like exercise and herbal teas.