Northern Arizona University, Science
Daily
It's also because research shows that it lowers
blood pressure and his new study reveals that it improves attention, which is
especially important when hitting that midday slump.
"Chocolate
is indeed a stimulant and it activates the brain in a really special way,"
said Stevens, a professor of psychological sciences at NAU. "It can
increase brain characteristics of attention, and it also significantly affects
blood pressure levels."
Historically,
chocolate has been recognized as a vasodilator, meaning that it widens blood
vessels and lowers blood pressure in the long run, but chocolate also contains
some powerful stimulants. Stevens said his team wanted to investigate if people
who consume chocolate would see an immediate stimulant effect.
Stevens
and his colleagues in the Department of Psychological Sciences performed the
EEG study with 122 participants between the ages of 18 and 25 years old. The
researchers examined the EEG levels and blood pressure effects of consuming a
60 percent cacao confection compared with five control conditions.
Michelle
Montopoli, an NAU alumna and student at the time of the study, led the EEG
testing phase which included measuring serving sizes of the samples based on
participant weight and packaging them so the participants were blind to what
they were tasting. Constance Smith, professor of psychological sciences,
assisted with the physiological analyses.
The
results for the participants who consumed the 60 percent cacao chocolate showed
that the brain was more alert and attentive after consumption. Their blood
pressure also increased for a short time.
"A
lot of us in the afternoon get a little fuzzy and can't pay attention,
particularly students, so we could have a higher cacao content chocolate bar
and it would increase attention," Stevens said. He added that a regular
chocolate bar with high sugar and milk content won't be as good, it's the
high-cacao content chocolate that can be found from most manufacturers that will
have these effects.
The
most interesting results came from one of the control conditions, a 60 percent
cacao chocolate which included L-theanine, an amino acid found in green tea
that acts as a relaxant. This combination hasn't been introduced to the market
yet, so you won't find it on the candy aisle. But it is of interest to Hershey
and the researchers.
"L-theanine
is a really fascinating product that lowers blood pressure and produces what we
call alpha waves in the brain that are very calm and peaceful," Stevens
said. "We thought that if chocolate acutely elevates blood pressure, and
L-theanine lowers blood pressure, then maybe the L-theanine would counteract
the short-term hypertensive effects of chocolate."
For
participants who consumed the high-cacao content chocolate with L-theanine,
researchers recorded an immediate drop in blood pressure. "It's
remarkable. The potential here is for a heart healthy chocolate confection that
contains a high level of cacao with L-theanine that is good for your heart,
lowers blood pressure and helps you pay attention," Stevens said.
Stevens
hopes the results of this study will encourage manufacturers to investigate
further and consider the health benefits of developing a chocolate bar made
with high-cacao content and L-theanine.
"People
don't generally eat chocolate and think it's going to be healthy for
them," Stevens said. He added that there is a possibility the millions of
hypertension patients in the country could eat a bar of this heart healthy
chocolate every afternoon and their blood pressure would drop into the normal
range, and they would be more alert and attentive.
