That advice applies to so many things in life. It seems that every aspect of modern living has been turned into a commodity.
Recently, the New York Times published this story about the incredible influence the sugar industry has bad over food production and health advice over the past several decades. It should remind you of the tactics used by tobacco executives and it should make you angry.
"The internal sugar industry documents, recently discovered by a researcher at the University of California, San Francisco, and published Monday in JAMA Internal Medicine, suggest that five decades of research into the role of nutrition and heart disease, including many of today’s dietary recommendations, may have been largely shaped by the sugar industry."
If you want to learn more, check out the documentary Sugar Coated. It's on Netflix and it's worth a watch.