human
Is it true that if you drink too much coffee you'll start yawning a lot and get headaches?
assistant
Yes, drinking too much caffeine can cause headaches. Caffeine is a stimulant and can increase the heart rate and blood pressure. High levels of caffeine intake can also lead to anxiety, restlessness, insomnia, irritability, nausea, and increased urination. Too much caffeine can also cause physical dependence and withdrawal symptoms when you stop consuming caffeine.