If it sometimes seems like health sciences professionals are constantly changing their minds about what's good or bad for you, maybe it's because some of them are just lousy scientists:
New research highlights a frustrating fact about science: What was good for you yesterday frequently will turn out to be not so great tomorrow.
The sobering conclusion came in a review of major studies published in three influential medical journals between 1990 and 2003, including 45 highly publicized studies that initially claimed a drug or other treatment worked. Subsequent research contradicted results of seven studies -- 16 percent -- and reported weaker results for seven others, an additional 16 percent. That means nearly one-third of the original results did not hold up, according to the report in Wednesday's Journal of the American Medical Association.
