(Reuters Health) – About half of American adults believe in at least one medical conspiracy theory, according to new survey results.

Some conspiracy theories have much more traction than others, however.

For example, three times as many people believe U.S. regulators prevent people from getting natural cures as believe that a U.S. spy agency infected a large number of African Americans with the human immunodeficiency virus (HIV).

via You’re Not Alone: Medical Conspiracies Believed By Many | Reuters.