Saturday, February 1, 2014

Caffeine

“Caffeine” by T. R. Reid, photographs by Bob Sacha, from "National Geographic" magazine, January 2005:

Richard Wurtman knocks back at least a quart of coffee a day. The MIT medical researcher credits the 600-plus milligrams of caffeine in his daily mugs with sharpening his mind and focusing his creativity.

No fan of what he calls “the waves of sugar” in Coke, MIT graduate student Nathan Wilson mixes his own power tonic for a long night’s work in the neuroscience lab. He quarters a 200-milligram caffeine pill and dissolves 50 mg in Gatorade. Wilson is part of a huge market: Every year U.S. consumers spend 30 million dollars on caffeine tablets and an estimated 50 billion dollars on caffeinated soda.

Living on a 43-hour “day (29 hours awake, 14 asleep) during a month-long study at Brigham and Women’s Hospital in Boston, Conor O’Brien (left) and 15 other volunteers took a pill every waking hour. Some got placebos, some got caffeine. Project head Charles Czeisler and his team concluded that frequent small amounts of caffeine maintain alertness better than the classic morning jolt from a big cup of coffee – fine-tuning our understanding of the drug’s numerous physical effects.

Military studies of subjects who hadn’t slept for 48 hours showed that 600 mg of caffeine improved alertness and mood as much as 20 mg of amphetamine.
Allowed just three hours of sleep in 52 hours of running, target shooting, and vigilance excercises, weary soldiers in Canada’s Operation Nighthawk tested chewing gum with 100 milligrams of caffeine per stick as a “fatigue countermeasure.” Absorbed directly through membranes in the mouth, chewed caffeine goes to work three times faster than caffeine in drinks or pills.
 
Going without caffeine for a day and a half increases bloodflow to the brain, which may explain why people get headaches, when they first give it up.
Your Brain on Caffeine -
Feel fuzzy-headed without your morning java? When users accustomed to a daily average of 650 milligrams of caffeine (about three 12-ounce cups of coffee) went without their usual fix, visual and auditory activity in the brain (indicated by bright colors in the scans at left) was low. Giving them 250 mg of caffeine boosted activity – but only up to levels equal to those of infrequent users who’d had no caffeine. “If you regularly get a hefty dose,” says Wake Forest University researcher Paul Laurienti, “you need it for your brain to function normally.”
Paul Laurienti, Advanced Neuroscience Imaging Research Laboratory, Wake Forest University School of Medicine (All brainscan images)

Here’s what’s missing from your decaf: A shovelful of caffeine and wax residues rises from the muck as workers decaffeinate coffee beans at a plant in Trieste, Italy.

The caffeine extracted from coffee beans to make decaf is sold to drug and soft drink manufacturers. Studies at the University of Connecticut’s Human Performance Laboratory suggest that caffeine does not cause dehydration in moderate amounts. Contrary to popular belief, our bodies retain as much fluid from caffeinated liquids as they do from water. That’s good news for Finns, who drink more coffee per capita than anyone else. The average Finn ingests an estimated 145 grams of caffeine a year.