From KnowledgeNews.net (subscription required), here's some info about how coffee affects your brain:

Coffee drinkers will tell you that their brains don't really work until they've had their morning cups. Well, this week, neuroscientists announced that those caffeinated cups may actually protect drinkers' brains--by shoring up a remarkable bit of anatomy known as the blood-brain barrier. Marvelous Membrane First noticed by doctors more than 100 years ago, the blood-brain barrier is a sort of physiological filtering system inside the tiny capillaries (blood vessels) inside your head. It helps to protect your brain from chemicals and other "foreign bodies" that may be floating in your blood, including things that do you no harm as long as they don't invade your brain. By allowing only certain tiny molecules to squeeze between protective cells, the blood-brain barrier protects your mental machinery from infection--even as it enables essential communication between your brain and your blood. "Great," you say, "but what does that have to do with my coffee?" Maybe a lot, especially if your diet isn't perfect. A new study by U.S. researchers suggests that a daily caffeine supplement, equivalent to a single cup of joe, could help keep your blood-brain barrier hale and hearty. Caffeine vs. Cholesterol Previous research has shown that high cholesterol can lead to "leaks" in the blood-brain barrier (and may play a role in the development of Alzheimer's disease). Meanwhile, other previous research has pointed to a possible connection between brain health and coffee drinking. So, for 12 weeks, the researchers fed lab rabbits high-cholesterol diets. They also gave some of their rabbits daily caffeine supplements. Then they tested the rabbits' blood-brain barriers for damage. Result: the caffeinated rabbits had significantly less blood-brain barrier leakage. Of course, that doesn't mean your doctor is about to start prescribing coffee. But it certainly is food for thought. As the study's lead researcher notes, "caffeine is a safe and readily available drug, and its ability to stabilize the blood-brain barrier means it could have an important part to play in therapies against neurological disorders." Plus, it's one medicine many would find easy to swallow. --Steve Sampson