Do you tend to think that herbs are “natural” and therefore can’t do you any harm? An analysis by Consumer Reports has some very different conclusions.

The magazine’s research found that the dietary supplements , which supposedly aid in curing everything from allergies to erectile dysfunction, have in fact been linked to a number of dangerous conditions including liver damage and high blood pressure and, occasionally, death.

Two scary facts to keep in mind: The herbal supplement market is a multibillion-dollar one, meaning that millions of Americans are using these substances, and they are not regulated by the federal Food and Drug Administration or by any other regulatory agency.

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The herbs listed by Consumer Reports are: aconite, bitter orange, chaparral, colloidal silver, coltsfoot, comfrey, country mallow, germanium, greater celandine, kava, lobelia and yohimbe.

And Nancy Metcalf, a Consumer Reports editor, cautioned that just because a substance is not on the list doesn’t mean it’s safe. “The dozen we call out in this report are by no means the only dangerous ingredients," Metcalf told www.webmd.com. "They are the ones we chose to highlight."

For more details on the side effects of the “dirty dozen” substances, click here. (Consumer Reports, WebMD)