Caffeine and depression: Is there a link?

The exact relationship between caffeine and depression isn't clear. There's no evidence that caffeine — a mild stimulant — causes depression. However, some people are more sensitive to the effects of caffeine than are others. In such individuals, caffeine may worsen existing depression. How or why this occurs isn't clear. But several theories exist.

• Although caffeine initially gives you a "lift," it may later have the opposite effect as the effects of the caffeine wear off.
• Caffeine can make it more difficult to fall asleep and stay asleep. A lack of sleep can worsen depression.
• Caffeine appears to have some effect on blood sugar, especially in people with diabetes. Fluctuations in blood sugar can be associated with mood changes.

If you have depression, you may consider limiting or avoiding caffeine to see if it helps improve your mood. However, caffeine can be habit-forming. So an abrupt decrease in caffeine can cause withdrawal symptoms, such as headaches, fatigue, irritability and nervousness. To lessen these withdrawal effects, gradually reduce the amount of caffeine you consume. For example, drink one fewer can of caffeinated soda or one fewer cup of caffeinated coffee a day.