Preregistration of clinical trials causes medicines to stop working<p><a href="http://chrisblattman.com/2016/03/01/13719/" rel="nofollow">http://chrisblattman.com/2016/03/01/13719/</a><p>...nuff said
It would perhaps be more accurate to say "Health news stories about medical studies are almost always bogus". There are several steps between those two things, and university PR departments, funding agencies, researchers, reporters of highly variable technical background, editors, and publishers all have incentives to twist the message at each step along the way.