Around 80% of the United States population consumes caffeine regularly, according to data from the U.S. Food & Drug Administration. Caffeine is found in coffee, tea, energy drinks, and some headache medications.

The National Center for Biotechnology Information says caffeine is the most widely consumed nervous system stimulant. Caffeine is considered a psychoactive drug. That means it alters the mind. Caffeine can change the way people think and feel. Healthline says the stimulating effects of caffeine contribute to its popularity. Caffeine will cause immediate alertness and temporarily relieve fatigue. Caffeine also may help enhance mood, and Healthline reports that one study found caffeine was linked to a 45% reduced risk of suicide in participants.

Moderate amounts of caffeine can increase focus and attention, and boost endurance while playing sports or engaging in other physical activities. When used in low to moderate amounts, caffeine can be beneficial. However, the following problems can occur when greater amounts are consumed.

  • Confusion and overstimulation
  • Headaches from too much caffeine or from withdrawal
  • Irritability can occur due to withdrawal if the body becomes accustomed to caffeine
  • Caffeine may help keep a person regular, but too much can cause diarrhea
  • Excessive caffeine can prevent calcium absorption in the bones, increasing the risk for osteoporosis and bone fractures
  • Some women who consume too much caffeine may have trouble conceiving a baby
  • When consumed in high amounts during pregnancy, there’s a risk of developmental issues in newborns or possibly miscarriage
  • Increased blood pressure also may result from consuming caffeine in high amounts.

Caffeine can have many effects on the body. It’s important to understand both the positive and negative impact of caffeine on the body and brain.