Currently the internal use of comfrey is restricted in
Canada, Brazil, Australia, and England. England has
restricted use of the roots and has recommended that animals
not be exposed for an extended period. In the US the
American Herbal Products Association has restricted the
internal use of comfrey.
The original research about comfrey was by Bruce Ames who
believes we worry too much about chemical pollutants and not
enough about naturally toxic substances. To prove his point
he researched natural substances and pointed at problems.
Another substance he exposed was peanut butter. This style
of "science on a mission" has become a commercial product
today and isn't very popular with more objective researchers.
Many of them take a slightly different view.
Even thought the alkaloids in comfrey can accumulate few
researchers see a problem in occasional usage. Many common
herbs have small quantities of toxic substances which are not
a problem. For example, the herb echinacea is used extensively
and has several toxic compounds. The current concern with
comfrey now focus on increased risk of cancer when the herb
is used continuously.
In other words, making tea out of mature leaves before the
plant flowers is probably safe and animals who have mixed
forage will not be at risk. The two deaths attributed to
comfrey required up to ten cups of tea a day and additional
pills over an extended period of time. For perspective we
should consider that coffee also has toxic substances and
excessive intake can cause serious problems..
Comfreys bad publicity has removed its title of "miracle
plant" and the alternative press doesn't rave about it
anymore, but should it be ignored? Next, we look at the good
news.
jeff (thinks this list has marginal critics, no one
complained about my spelling of "comfry" in post #1)
