How much caffeine I can take?

If you rely on caffeine to wake you up and keep you going, you aren't alone. Caffeine stimulates the central nervous system, alleviating fatigue and increasing wakefulness.

For most people, moderate doses of caffeine — 200 to 300 milligrams (mg), or about two to four cups of brewed coffee a day — aren't harmful. But some circumstances may warrant limiting or even ending your caffeine routine.

To change your caffeine habit more gradually, try these tips: 
1. Keep tabs. Start paying attention to how much caffeine you're getting from foods and beverages. It may be more than you think. Read labels carefully. Even then, your estimate may be a little low because not all foods list caffeine. Chocolate, which has a small amount, doesn't.
2. Cut back. But do it gradually. For example, drink one less can of soda or drink a smaller cup of coffee each day. This will help your body get used to the lower levels of caffeine and thereby lessen the withdrawal effects.
3. Go decaf. Most decaffeinated beverages look and taste the same as their caffeinated counterparts.
4. Make it quick or herbal. When making tea, brew it for less time. This cuts down on its caffeine content. Or choose herbal teas, which don't contain the stimulant.
5. Check the bottle. Some over-the-counter pain relievers contain caffeine — as much as 130 mg of caffeine in one dose. Look for caffeine-free pain relievers instead.