Paul John Scott's June 22 commentary ("Chocolate milk in the schools and other products of expert opinion") about the follies and outright deceptions in yesteryear's low-fat diet "science" cannot be read without seeing parallels to today's climate-change debate.
Scott points out that the good intentions of a passionate scientist do not equate to good scientific reasoning or sound government policy. In the case of the saturated-fat-causes-heart-disease hypothesis, which for decades erroneously guided federal and local school policies, it turns out that researcher Ancel Keys reportedly hid evidence (including 600 questionnaires) that didn't comport with his opinion of the origin of coronary disease. Naysayers were put on the defensive against this fad science.
Scott also indicts the "eager and unquestioning health press," including the redoubtable Time magazine, which in 1961 put Keys on its cover, which reminds me of the equally redoubtable Newsweek that in 1975 proclaimed an inevitable coming ice age.
Oops. What lesson can we learn from these two stories?
As a nation, we are quick to adopt dietary fads, and also to accept the authority of media and government. Oops, indeed.
Now, after decades of scientific review, whole milk, butter and bacon are exonerated from causing coronary disease. (Obesity is a different subject altogether.) Sugar and food preservatives don't cause hyperactivity, contrary to the widely published inspirations of Dr. Benjamin Feingold in the 1970s-90s.
Should these lessons not give us pause about the so-called "settled science" about climate change? No side of the climate debate can claim the high ground, especially when the inconvenient measured fact is that earth's average temperature has not risen in the last 17 years, that doomsday projections are based on speculative models, not fact, and that higher CO2 levels may have as many positive effects as negative. We just don't know.
Though world temperatures are higher than they were in the 18th century, the science isn't settled on what all of the causes are, what the human contributions are or what to do about them.