Caffeine is a bitter substance found in coffee, tea, soft drinks, chocolate, some nuts and certain medicines. It has many effects on the body’s metabolism, including stimulating the central nervous system. This can make you more alert and give you a boost of energy.

Caffeine blocks the action of adenosine receptors which in turn increases dopamine levels. Dopamine is a brain chemical associated with reward, pleasure, movement and motivation. High on dopamine brought to you by caffeine.

The amount of caffeine in 2-4 cups of coffee/day is usually not harmful for most. Be aware that too much caffeine may make you restless, anxious and irritable. It could be what’s keeping you from a good night’s sleep and may cause headaches, abnormal heart rhythms or other physical problems.

Some people are more sensitive to the effects of caffeine, so no caffeine high for them. If you stop using caffeine to get your dopamine high, you may experience withdrawal symptoms. A headache is one.

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