This
NY Times article talks about a study that once again, and in new ways, refutes any claims to a cold remedy.
Some cool quotes.
The study, being published today in The New England Journal of Medicine,
involved 437 people who volunteered to have cold viruses dripped into their
noses. Some swallowed echinacea for a week beforehand, others a placebo.
Still others took echinacea or a placebo at the time they were infected.
Then the subjects were secluded in hotel rooms for five days while
scientists examined them for symptoms and took nasal washings to look for
the virus and for an immune system protein, interleukin-8. Some had
hypothesized that interleukin-8 was stimulated by echinacea, enabling the
herb to stop colds.
But the investigators found that those who took echinacea fared no
differently from those who took a placebo: they were just as likely to
catch a cold, their symptoms were just as severe, they had just as much
virus in their nasal secretions, and they made no more interleukin-8.
Now, with increasing evidence that echinacea does not work for colds,
scientists are confronting a problem, Dr. Sampson said, in that "there is
no 'demarcation of the absurd,' a point at which it is unwise to pursue an
investigation further."
For Dr. Turner, that point is here.
"We should assume that echinacea does not work until somebody proves it
does," he said. That, he added, "is the flip side of where we've been."