The connection between tobacco smoke, cancer and heart disease has been well established since the 1800's, with irrefutable medical evidence presented since the 1950s. There is no question that smoking has significant public health impacts. The effects of second hand smoke were examined in various studies and  also claimed negative effects. But these reports has some significant limitations, and larger studies later showed no significant risk.  One of the authors, cancer epidemiologist Dr. Geoffrey Kabat, recounts the publication, the fallout, the lack of defense from the scientific community, and later independent reports that would reinforce their findings of no association with lung cancer and heart disease. While predating social media, the findings that did not fit a public health narrative where harshly criticized, using arguments that failed to address the evidence. This example is a precursor to understanding the modern-day discussions about issues like vaccination, COVID19, glyphosate, and other topics where the evidence is strong, but public opinion often fails to accept it.

Dr. Kabat's accompanying article on Quillette.