You say it's science. I say it's meddling, overbearing government using whatever wedge it can find:
“In any compromise between food and poison, it is only death that can win,” wrote Ayn Rand. And, with considerably more charm, Mark Steyn wrote, “It’s a good basic axiom that if you take a quart of ice-cream and a quart of dog feces and mix ’em together the result will taste more like the latter than the former.”
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Likewise, if you mix science with meddling overbearing government, you get meddling overbearing government. Note these recent stories about nutrition. The scientists who help compose the federal nutritional guidelines that govern what goes into subsidized school lunches have finally admitted that eating cholesterol — as in eggs, say — doesn’t actually increase your cholesterol, and skipping breakfast, well known to make people fat, doesn’t make people fat. At the same time, the researcher who once found important evidence for the existence of gluten sensitivity recently proved pretty much beyond a doubt that gluten sensitivity (barring celiac disease) doesn’t actually exist.
Put all these discoveries together and what you realize is that when a meddlesome overbearing government fronted by Michelle Obama mandates school lunches that are universally decried as “gross” by people who eat school lunches, that’s not science — it’s just meddling overbearing government.
Or try this. Read this 1989 article in which “a senior environmental official at the United Nations” declared “entire nations could be wiped off the face of the earth by rising sea levels if global warming is not reversed by the year 2000…. Coastal flooding and crop failures would create an exodus of ‘eco-refugees,’ threatening political chaos.” Now look out your window. Hmm. Pretty bad out there, I know. But at least it’s not as bad as the global ice age a “leading atmospheric” NASA scientist predicted in 1971 or the global warming catastrophe that UN scientists predicted in 2007 could destroy us as soon as last year. (h/t Real Science website.)
Science always takes the long view. We take what we know now and build on it, uncertain of what we'll find but willing to wait until the pieces fall into place, and knowing that won't be the last stop, either.. Government takes what we know now, at this prcise moment, pretends it knows what that means for tomorrow and demands we take immediate, drastic, costly measures.
The government has been so wrong about so much nutritional advice, it wouldn't be a bad strategy just to listen to what it says, then do just the opposite.