About the actions of caffeine

Since weeks I intended to post a few lines about caffeine, because  there is currently a lot of buzz about this substance. The German Newsletter »DocCeck«, says it is as good as painkillers and it helps to cure those ones who overreached their workout and suffer therefore from a kind of workout burnout as they call it.
Moreover I bumped into a summary of studies presenting more controversial results. While 200mg of caffeine seems to reduce the capacity of healthy volonteers to retrieve knowledge, caffeine increases mental alertness. The explanations may sound probably not too logical to you. The scientists say that higher alertness goes along with the shut-down process of certain brain areas (International School for Advanced Studies in Triest, Italy).

Another study performed at the University of Innsbruck, Austria, found out that 100mg caffeine improve our memory by increasing neuronal activity in our brains front lobe. A group in Birmingham has got data that indicate that caffeine protects our brains from loosing our memory. Caffeine as some kind of dementia prophylaxis Perhaps?!

An Australian study group stresses that 200mg of caffeine make people more open for new arguments and ideas. They say caffeine because of its effect on neurons improves our capacity of logical thinking. Caffeine helps us to stay focused.

Isn’t that fantastic. But don’t be too optimistic. There also data that say caffeine increases stress, but in males only. In females it seems to reduce the stress level. And another study result is not too encouraging for some of you: Alcohol and caffeine together don’t increase performance.

Regardless of all the controversies around this substance it is definitely a powerful ingredient. To make my resumée complete I want to add a post from an interesting blog that might occasionally be useful for you http://drugsandpoisons.blogspot.com/

Here are some things about caffeine that you very possibly were not aware of:

• Caffeine is a methylxanthine found in coffee – other methylxanthines include theophylline (in tea) and theobromine (in cocoa) inhibits phosphodiesterase and blocks the action of adenosine, thus making it easier for your muscles to contract (caffeine can cause muscle tissue to contract in vitro)
• Caffeine is used to diagnose people who have a genetic predisposition to malignant hyperthermia, a condition invoked by general anaesthesia that causes your muscles to intensely contract, producing tonnes of heat such that you run an exceptionally high fever and the enzymes in your body begin to stop working and you die very quickly (can be treated with dantrolene, hyperthermia is also a side effect of ecstasy use)
• Caffeine can be used to treat asthma, since it causes bronchodilation (relaxes the smooth muscle of the airways, causing them to expand – constriction of this muscle occurs during an asthma attack)
• Other effects include increased alertness (nervousness and insomnia at high doses), positive chronotropic and inotropic effects (i.e. increased heart rate and increased force of heart contraction, respectively), vasodilatation (except in brain), and weak diuresis (i.e. increases how much urine your kidney makes)

http://drugsandpoisons.blogspot.com/2006/12/caffeine.html

Kalant H, Grant D, and Mitchell J. Principles of Medical Pharmacology 7th ed. Toronto: Saunders Canada, 2006.