- Many people say they need a cup to function
- Coffee is not addictive when consumed
in reasonable quantities, researchers in France have found.
- Most coffee drinkers say they function
better after their first cup of the day.
- But scientists have debated whether caffeine
- the active ingredient in the drink - is addictive.
- Some people fear they grow dependent
on drinks containing the chemical.
- The study suggests this is unlikely,
although the finding runs contrary to previous research.
- Chemical conference
- The new research is being presented at
a national meeting of the American Chemical Society, which claims to be
the world's largest scientific society.
- It was conducted by Dr Astrid Nehlig,
research director at the Strasbourg laboratory of INSERM, the French National
Health and Medical Research Institute.
- She said that at doses of one to three
cups of coffee a day, caffeine has no affect on the area of the brain involved
with addiction, dependence and reward.
- She recently completed a study with laboratory
- It confirmed what any coffee drinker
could tell you - that caffeine consumed in moderation contributes to increased
alertness and energy.
- But contrary to some findings, it found
coffee does not bring about dependence at those levels.
- Hard drug comparison
- Dr Nehlig said caffeine appears to act
differently from undeniably addictive substances such as amphetamines,
cocaine, morphine or nicotine.
- Even at low doses, these drugs trigger
activity in the shell of the nucleus accumbens - the part of the brain
responsible for addiction, she said.
- It would take the equivalent of about
seven or more cups of caffeinated coffee consumed in rapid succession to
begin to activate this portion of the brain.
- Even then, she said, "activation
of the circuitry of addiction and reward occurs only at high doses of caffeine,
which probably induce already adverse effects".
- These effects include anxiety, nervousness
and depression, she said.
- Dr Nehlig acknowledged that there is
a "big debate" among researchers about whether caffeine is addictive.
- She said one study " reported dependence
over a wide dose range", from as little as one or two cups per day
to as much as 25 cups.