2007-10-16 07:20:10
Researchers have cracked the mystery of why eating garlic can help keep the
heart healthy.
The key is allicin, which is broken down into the foul-smelling sulphur
compounds which taint breath.
These compounds react with red blood cells and produce hydrogen sulphide which
relaxes the blood vessels, and keeps blood flowing easily.
The University of Alabama at Birmingham research appears in Proceedings of the
National Academy of Sciences.
Our results suggest garlic in the diet is a very good thing
Dr David Kraus
University of Alabama
However, UK experts warned taking garlic supplements could lead to side
effects.
Hydrogen sulphide generates a smell of rotten eggs and is used to make stink
bombs.
But at low concentrations it plays a vital role in helping cells to communicate
with each other.
And within the blood vessels it stimulates the cells that form the lining to
relax, causing the vessels to dilate.
This, in turn, reduces blood pressure, allowing the blood to carry more oxygen
to essential organs, and reducing pressure on the heart.
The Alabama team bathed rat blood vessels in a bath containing juice from
crushed garlic.
Striking results
This produced striking results - with tension within the vessels reduced by
72%.
The researchers also found that red blood cells exposed to minute amounts of
juice extracted from supermarket garlic immediately began emitting hydrogen
sulphide.
Further experiments showed that the chemical reaction took place mainly on the
surface of the blood cells.
The researchers suggest that hydrogen sulphide production in red blood cells
could be used to standardise dietary garlic supplements.
Lead researcher Dr David Kraus said: "Our results suggest garlic in the diet is
a very good thing.
"Certainly in areas where garlic consumption is high, such as the Mediterranean
and the Far East, there is a low incidence of cardiovascular disease."
Judy O'Sullivan, a cardiac nurse at the British Heart Foundation, said: "This
interesting study suggests that garlic may provide some heart health benefits.
"However, there remains insufficient evidence to support the notion of eating
garlic as medicine in order to reduce the risk of developing coronary heart
disease.
"Having garlic as part of a varied diet is a matter of personal choice.
"It is important to note that large amounts in supplement form may interact
with blood thinning drugs and could increase the risk of bleeding."