The Dawn of Caffeine....know how it works !!!

Hi everybody,

I read this article and thought of sharing it with u'll....
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Passing by thousands of foods n drinks on grocery store shelves, almost 90% of the adults crave one item every day - caffeine.

Whether it provides a quick morning pick-me-up or boost of energy as the afternoon drags on, cafeine is a bitter-tasting chemical that grows naturally in coffee, tea, and cocoa beans. Caffeine also is an ingredient used to enchance sodas and pain relievers.

For those wondering how caffeine opens eyes around the world, scientists believe it stands in the way of the brain's "off switch," a chemical called adenosine. When brain cells are overworked and tired, adenosine comes along like a natural sleeping pill. As more adenosine is released, brain cells shift into idle and drowsiness sets in.

Caffeine, however, tricks brain cells by blocking the spots where adenosine would normally enter. Instead of slowing down because of the adenosine level, cells speedup. Brain activity increases so we feel alert and energized. All the excitment in the brain triggers other reponses - the heart beats faster, blood vessels adjust flow, breathing tubes expand, and muscles tighten.

Obivously this can have negative effects on sleep. After a cup of coffee, some people may lie awake for hours. Others will nod off, but their sleep will be disrupted and they'll lose out on the benefits of deep sleep.

As one of the most widely studied subtances in the world, caffeine is not the villain it appears to be. In moderation - usually defined as 300 milligrams per day - caffeine does not seem to have ill effects on healthy adults. Many organizations, including the American Heart Association and the Center for Science in the Public Interest, say caffeine is safe within modest limits.

But the supersizing prompts concern among some physicians. Sipping a six-ounce cup of steaming coffee 50 years ago has morphed into the gulping of 32-ounce sugary treats packed with the most potent java possible. Plus many of us overlook caffeine from soda, chocolate, and headache medicine.

The only way to bring caffeine within the 300-milligram-a-day range is to crunch the numbers and, if they add to your caffeine confusion, consult your doctor.

Brewed coffee, 8 ounces - 65 to 250 mg.
Brewed tea, 8 ounces - 20 to 90 mg.
Soft drinks, 8 ounces - 15 to 83 mg.
Dark chocolate, 1 ounce - 5 to 35 mg.
Milk chocolate, 1 ounce - 1 to 15 mg.
Excedrin, 2 caplets - 130 mg.
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Jay