Coffee and Caffeine

Refill, anyone? Here are a few freshly brewed notes on coffee and caffeine, the most widely used stimulant in the world.

Researchers have demonstrated that short-term memory skills and reaction times are heightened after consuming caffeine. While this might not come as news to anyone who uses coffee to clear the fog of sleep, it had not been scientifically proven before the announcement in November 2005. The researchers from the Radiological Society of North America were also fascinated to see, on a functional MRI test, that coffee drinkers showed increased activity in the parts of the brain that control working memory and attention.

Coffee can be habit-forming but has not been proven truly addictive. The painful symptoms of caffeine withdrawal, however, are quite real. Even people whose sole caffeine hit is a daily 12-ounce cup of joe in the morning report headaches if they stop. Withdrawal symptoms can range from a mild headache, irritability and drowsiness to muscle aches, vomiting, blurred vision and even low-level depression. Nonetheless, anyone who tries hard enough can quit.

Like few other foods or drugs, caffeine is immediately absorbed through the stomach and intestines. Seconds after coffee hits the stomach, caffeine permeates the digestive tract’s soft lining and spreads throughout the body via the bloodstream. It’s fat soluble, it’s water soluble, it’s able to leap tall buildings in a single bound. Caffeine even crosses the blood-brain barrier, which is otherwise nearly impervious to molecular invasion. Once caffeine storms the castle walls of the brain, the drug sets loose the full potential of its stimulating effects.

One biological response to caffeine is that it opens up the oxygen-seeking bronchia in the lungs. This pans out well for smoking coffee drinkers since it provides them with oxygen they would otherwise strangle with cigarettes.

Caffeine gets a footnote in the study of osteoporosis, a disease that makes bones weak and brittle. Ingesting caffeine promotes the excretion of calcium (in urine), which, as every school kid knows, keeps bones strong. While not considered a cause of the infirmity, coffee does in this way contribute to the disease. People who are believed to be at risk for osteoporosis and choose to drink coffee can offset the calcium depletion with a daily glass of milk.

Find more on MSN Health & Fitness:

• Does Coffee Raise Cholesterol?
• Study: Coffee May Fight Liver Cancer
• Coffee Perks Up Short-Term Memory
• Should You Decaffeinate Your Diet?