But the new research suggests that Allicin and similar biologically active compounds are only a piece of the puzzle, and that it's the chemical messenger that is produced when these compounds are metabolized that is important.
In laboratory tests, the researchers at the University of Alabama found that it was this chemical messenger -- hydrogen sulphide (H2S) -- which is essential at low levels for cellular signaling, that appears to relax blood vessels, enhancing blood flow.
The finding may explain why some studies showed there were no cardiovascular benefits to be gained from taking garlic supplements while many others showed that such supplements could halt the progress of cardiovascular disease, the authors said.
"In addition, our results suggest that the capacity to produce H2S can be used to standardize garlic dietary supplements," the authors wrote.
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