[Paleopsych] NS: Decaff coffee gives a buzz too

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Decaff coffee gives a buzz too
http://www.newscientist.com/article.ns?id=dn3075&print=true

      * 10:31 19 November 2002
      * James Randerson

    The buzz from your morning cup of coffee may not be caused by caffeine
    after all. According to new research, decaffeinated coffee may be just
    as good at raising the blood pressure, at least for drinkers not used
    to the black stuff.

    Numerous studies have shown that too much caffeine interferes with
    sleep patterns, but the long term health effects of the drug are more
    controversial. Some scientists claim that daily caffeine stimulation
    increases our risk of high blood pressure and heart disease later in
    life.

    But overall, the evidence is equivocal, says Alice Lichtenstein of the
    American Heart Association's Nutrition Committee. Now, the small
    Swiss-led study suggests that to focus on caffeine alone may be wrong.

    The researchers gave triple espressos to six regular coffee drinkers
    and nine volunteers who never consumed food or drinks containing
    caffeine. On a separate occasion, the caffeine-abstainers also drank a
    triple decaffeinated espresso, but they were not told which was which.

    To the researchers surprise, both drinks had the same effect on the
    non-coffee drinkers, stimulating the sympathetic nervous system and
    raising blood pressure.

"Fake" hit

    One interpretation of the result is that the subjects are reacting
    like Pavlov's dog and receiving a "fake" caffeine hit in anticipation
    of the real thing. But lead researcher Roberto Corti, a cardiologist
    at University Hospital in Zurich, thinks this is unlikely because the
    volunteers did not usually drink coffee.

    "We also saw a linear trend in blood pressure. This is not typical of
    a placebo effect," he adds. A more likely explanation, he thinks, is
    that coffee components other than caffeine have a stimulating effect.

    But the study threw up other puzzling findings. Regular coffee
    drinkers did not experience higher blood pressure after normal coffee,
    but their nervous system was stimulated.

    Corti does not think this is due simply to their bodies having got
    used to the effects of caffeine, because an intravenous caffeine
    injection did raise their blood pressure. He believes that other
    chemicals in coffee might block the caffeine stimulation.

    But Lichtenstein says the result could be due to differences in the
    method of delivery. Absorption via the gut can be slow and depends on
    what the volunteer had in their last meal. "It's very different from
    mainlining caffeine," she says.

    "The study has raised questions," says Lichtenstein. But she thinks it
    is too early to draw broad conclusions on the effects of caffeine and
    coffee.

    Journal reference: Circulation (vol 106, p 2935)

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      * 8 November 2002
      * [14]Caffeine 'lotion' protects against skin cancer
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      * [16]Caffeine key to curing a headache
      * [17]http://www.newscientist.com/article.ns?id=dn1491
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Weblinks

      * [18]University Hospital, Zurich
      * [19]http://www.usz.ch/e/index.html
      * [20]American Heart Association
      * [21]http://www.americanheart.org/
      * [22]Caffeine FAQ
      * [23]http://coffeefaq.com/caffaq.html
      * [24]Circulation
      * [25]http://circ.ahajournals.org/

References

   12. http://www.newscientist.com/article.ns?id=dn3032
   13. http://www.newscientist.com/article.ns?id=dn3032
   14. http://www.newscientist.com/article.ns?id=dn2714
   15. http://www.newscientist.com/article.ns?id=dn2714
   16. http://www.newscientist.com/article.ns?id=dn1491
   17. http://www.newscientist.com/article.ns?id=dn1491
   18. http://www.usz.ch/e/index.html
   19. http://www.usz.ch/e/index.html
   20. http://www.americanheart.org/
   21. http://www.americanheart.org/
   22. http://coffeefaq.com/caffaq.html
   23. http://coffeefaq.com/caffaq.html
   24. http://circ.ahajournals.org/
   25. http://circ.ahajournals.org/