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Science AMA Series: I’m David Johns, from Columbia University’s Mailman School of Public Health. I study the history of scientific debates over the health risks associated with excessive consumption of sugar, salt, and fat. AMA!
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On February 16, my colleague Gerald Oppenheimer and I published an article in Science that challenged high-profile claims in the academic literature and popular press alleging that the sugar industry paid scientists in the 1960s to play down the link between sugar and heart disease and “shift the blame” to dietary fat instead. Our article focuses on documents unearthed in historical archives about sugar industry funding of Harvard nutrition scientists in the 1960s, which some experts have identified as “smoking gun” evidence that the sugar industry successfully meddled in science and “derailed” the course of dietary policy. We disagree with these widely publicized claims. As we write in our article, there was no “smoking gun.” Previously, my colleagues and I have explored the scientific debates around another controversial ingredient: salt. We analyzed a wide body of scientific reports on the health effects of a salty diet, and showed in a 2016 study that the field is sharply polarized between those who believe population-wide reduction of salt intake will lead to improved health and those who think the data are not convincing. I am not a nutrition scientist, and I don’t claim to have the final answers on the risks of consuming too much sugar or salt! But still: AMA! EDIT: I’M HERE! Thanks for the questions. I am going to start answering right now!!! EDIT 2: I have really enjoyed answering all of your excellent questions. Cheers! Sugar research: https://www.mailman.columbia.edu/public-health-now/news/researchers-challenge-claims-sugar-industry-shifted-blame-fat http://science.sciencemag.org/content/359/6377/747.full Salt research: https://www.mailman.columbia.edu/public-health-now/news/science-salt-polarized-study-finds https://academic.oup.com/ije/article/45/1/251/2363485 https://www.reddit.com/r/askscience/comments/48x6dv/askscience_ama_series_im_david_johns_a_doctoral/