instances, and in excess, these can have negative effects on our body, they can
also be quite beneficial.
I am not disputing that some people are more sensitive to the negative effects
of either caffeine or chocolate. For example, excess caffeine can create
anxiety, nausea (particularly if taken on an empty stomach), an increase in
heart rate, and even depression in some people. And chocolate is certainly not
something that should form the mainstay of one's diet. If struggling with sugar
addiction, or wanting to lose weight, there are more nutritionally complete
foods that are available.
But scientists have turned up some interesting facts on caffeine. For example,
caffeine actually blocks the effects of a neurotransmitter in the brain
(adenosine) that otherwise makes us feel tired. This is why it works so well to
keep us awake. It also encourages the release of another brain chemical,
dopamine (as well as adrenaline). Dopamine contributes to a feeling of well
being.
Two studies, one a population based study (which are not as specific or
rigorously defined as other types of studies, but nonetheless valuable
indicators) found that drinking caffeine containing drinks like coffee and tea
had a protective effect for those at risk of developing liver disease. Issues
that the study participants had that increased their risk of liver disease
included alcoholism, hepatitis B or C, obesity, or other complications.
And the results indicated that people who drank more than 2 cups of coffee a day
had a 44% lower chance of showing actual liver damage compared to those who
drank no caffeine. This was not a clinical trial, and the reason why coffee and
tea had such an effect is not known. Coffee and tea contain a range of plant
chemicals (phytonutrients) that could be responsible for this. A 2005 Norwegian
study also found similar benefits for coffee with regards liver disease. This
study found that drinking 3 cups of coffee a day could lower the risk of death
from liver cirrhosis.
Even if you're not at risk of liver disease, caffeine still has some advantages.
Recent research from Austria showed that caffeine may actually enhance short
term memory. Researchers found that there was an increase in brain activity (as
measured by functional magnetic resonance imaging) in the parts of the brain
that were associated with memory and attention. These parts of the brain were
the frontal lobe and the anterior cingulum. This was a placebo controlled study,
meaning that some people were not given any caffeine. Another, earlier study
(2004) found that caffeine did support short term memory, but only when it was in
relation to a topic that people were already thinking about. This study found
that when testing coffee's effects on unrelated subjects, short term recall was
actually inhibited.
Everything does have a flip side though. Adenosine, which is blocked by coffee,
is also calming. This could be why it can also cause anxiety in excess, and in
some individuals. After all, the balance of our brain chemistry is unique. And
when we are addicted to stimulants like caffeine, we lose the sensitivity to our
own natural stimulants (dopamine and adrenaline).