Caffeine

Caffeine is probably the world's most popular drug. It's basically a poison, a pesticide, used to keep pests away from coffee beans. And that's why decaffeinated beverages still contain trace amounts of caffeine because it's found in the plant. Caffeine reduces drowsiness and can enhance cognitive performance and vigilance such as improving problem solving, increase the capacity for physical work, and raise urine production. But at high doses, it creates tremors and anxiety. Long-tern effect can result in tolerance, as well as physical dependence. Withdrawal symptoms include headaches, fatigue, anxiety, shakiness, and cravings. It can last up to a week. Studies have indicated that caffeine may make it harder for women to become pregnant and increase the risks of miscarriages, stillbirths, and low birth weight babies. Moderate daily consumption may also lead to a slightly increased blood pressure.