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Top 10 Most Addictive Foods

Caffeine and Caffeinated Beverages

If you're a coffee drinker, then you probably won't argue that caffeine is addictive. The more caffeine you ingest during the day, the more likely you'll suffer withdrawal symptoms when that caffeine is taken away. We're not just talking about coffee, either. You'll also find caffeine in tea, energy drinks, soda and even chocolate.

Because caffeine is a mild stimulant, you feel more energized after having some. But if you skip your regular intake, you might find yourself feeling sluggish or headachy. That's because caffeine actually prevents headaches by blocking the brain receptors that dilate blood vessels, the cause of that headache. In fact, some aspirin and other pain relief products contain caffeine for that very reason.

Doctors report that caffeine withdrawal symptoms can start as soon as 12 hours after your last cup of Joe, and they can last as long as a week!