Sadly the evidence is that like other addictions having a coffee just restores your energy and cognitive ability to where it would be if you hadn’t started down that rocky path of having a daily dose of caffeine.
There is however some good news. Drinking too much coffee can give you the shakes but for sufferers from Parkinson’s disease it has the opposite effect.
Scientists knew that drinking coffee had a prophylactic effect and reduced the risk of Parkinson’s but had never tested what happened with people who already had the disease.
Researchers at McGill University in Montreal, Canada, gave Parkinsons’ sufferers either a 6-week course of caffeine pills, equivalent to three cups of coffee a day, or a placebo.
Only people in the caffeine group showed a significant improvement in tests for motor problems such as tremors and general mobility.
Motor problems are caused by lack of dopamine in the brain and caffeine blocks the receptors that inhibit its production.
Source: New Scientist 4/8/2012