Politics + Nutrition Advice/Policy invariably screws you. Because politics.

The untold story of how the sugar industry shaped key government research about your teeth - The Washington Post: "Decades-old documents have surfaced showing that the powerful U.S. sugar industry skewed the government's medical research on dental care—and ultimately what officials recommended for American diets. Despite a widespread understanding that sugar played a key role in tooth decay, sugar industry leaders advocated for policies that did not recommend people eat less sugar, according to an archive of industry letters dating back to the 1950s preserved by the University of Illinois and analyzed by a team of researchers at the University of California in San Francisco. And the government listened, according to a new report published in the journal PLOS Medicine. In the 1960s, amid a national effort to boost cavity prevention, the U.S. government spearheaded a research program, known as the National Caries Program (NCP), which aimed to eradicate tooth decay by the end of the 1970s. 

 But instead of turning to an obvious solution—having people eat less sugar—the government was swayed by industry interests that pushed alternative methods, such as ways to break up dental plaque and vaccines for fighting tooth decay, according to more than 300 internal industry documents, including old letters and meeting minutes. How did the industry wield so much power? For one, the sugar industry had a strong presence in the subcommittee that developed the very research priorities that later guided dental care policies. A task force committee that was set up by the government to set research priorities for the NCP included many doctors and scientists who were also working closely with the sugar industry. These committee members were also part of another group called the International Sugar Research Foundation, which was established by the sugar industry."