Industry-Funded Study Hid Sugar's Links to Heart Disease: Report

Marcia Frellick

September 13, 2016

SAN FRANCISCO, CA – The sugar industry paid for and was closely involved in development of an influential literature review, published by the New England Journal of Medicine in 1967[1,2], that downplayed dietary sugar's links to coronary heart disease while pointing the finger at fat and cholesterol intake, according to a report published September 12, 2016 in JAMA Internal Medicine[3].

The sugar industry's funding and other participation were not disclosed in the 1967 articles, which had a major influence on dietary recommendations for sugar in the following decades, notes the new analysis from Dr Cristin E Kearns (University of California, San Francisco) and colleagues.

The literature review from almost 50 years ago served as a lobbying tool for the industry and likely influenced the first dietary guidelines of the 1980s, Kearns told heartwire from Medscape. It put the focus on dietary cholesterol and took the focus off sugar intake as a risk factor for heart disease, she said; if the evidence had been fairly presented, the recommendations would have been to reduce both fat and sugar, not just saturated fat.

"That was the message that guidelines hammered home for decades…that it's the fat you really need to worry about," she said. "The conversation about sugar was left out." Kearns is with her institution's Philip R Lee Institute for Health Policy Studies and Department of Orofacial Sciences.

What is clear, she and her colleagues write, is that today, "the sugar industry, led by the Sugar Association, the sucrose industry's Washington, DC–based trade association, steadfastly denies that there is a relationship between added sugar consumption and CVD risk."

The group analyzed internal documents from the Sugar Research Foundation (SRF), the precursor to the Sugar Association, that had become available in academic libraries and other publicly accessible locations. They also reviewed historical reports and statements made in early debates about health effects of sugar. According to those documents, the group reports, the SRF set the journal's review's objective, contributed articles for inclusion, and received drafts.

Kearns and colleagues describe finding documentation that the SRF paid two nutrition researchers, Dr D Mark Hegsted and Dr Robert McGandy (Harvard School of Public Health, Boston, MA), to conduct the literature review; the payments amounted to about $48,900 in 2016 dollars.

Also among the evidence of influence, they write, is correspondence from July 30, 1965, to Hegsted from SRF vice president John Hickson. In it, they report, Hickson emphasized the SRF's objective for funding the review: "Our particular interest had to do with that part of nutrition in which there are claims that carbohydrates in the form of sucrose make an inordinate contribution to the metabolic condition, hitherto ascribed to aberrations called fat metabolism. I will be disappointed if this aspect is drowned out in a cascade of review and general interpretation."

Hegsted, the current report states, responded "We are well aware of your particular interest in carbohydrate and will cover this as well as we can."

Kearns and colleagues acknowledge there is "no direct evidence that the sugar industry wrote or changed the NEJM review manuscript" and that evidence that the industry influenced the conclusions is circumstantial.

The NEJM has required authors to disclose all potential conflicts of interest since 1984, the group writes. "Whether current conflict-of-interest policies are adequate to withstand the economic interests of industry remains unclear."

The Sugar Association responded to the report from Kearns and colleagues on September 12, 2016 with a statement: "We acknowledge that the Sugar Research Foundation should have exercised greater transparency in all of its research activities; however, when the studies in question were published, funding disclosures and transparency standards were not the norm they are today. Beyond this, it is challenging for us to comment on events that allegedly occurred 50 years ago and on documents we have never seen."

It continued, "We question this author's continued attempts to reframe historical occurrences to conveniently align with the currently trending antisugar narrative, particularly when the last several decades of research have concluded that sugar does not have a unique role in heart disease."

Smoking Gun?

In an invited commentary to the current report[4], Dr Marion Nestle (New York University, NY) notes that typically, when industry sponsors nutrition studies, disclosures state that the funder had no role in designing, conducting, interpreting, writing, or publishing the study and "without a smoking gun it is difficult to prove otherwise."

"Kearns and colleagues report on having found that smoking gun," she writes. "They have produced compelling evidence that a sugar trade association not only paid for but also initiated and influenced research expressly to exonerate sugar as a major risk factor for coronary heart disease."

She said the analysis shows the industry-funded review reached a foregone conclusion: "The investigators knew what the funder expected and produced it. Whether they did this deliberately, unconsciously, or because they genuinely believed saturated fat to be the greater threat is unknown. But science is not supposed to work this way."

Nestle says the findings should not be viewed as ancient history and that industry influence continues today in the food industry. She points out that in 2015 the New York Times obtained emails that revealed Coca-Cola's relationships with sponsored researchers conducting studies aimed at limiting effects of sugary drinks on obesity[5].

The findings from Kearns and colleagues are "appalling," according to Dr James J DiNicolantonio (Saint Luke's Mid America Heart Institute, Kansas City, MO). He told heartwire that while their findings show "probably the earliest evidence we have that this has been going on," sugar industry conflicts of interest continue today.

Some meta-analyses have favored short-term studies in looking at effects of sugar, he said, but because people have been consuming sugar in large quantities for so long, those short-term studies aren't going to show harm. "If you actually look at the studies that restrict sugar, so they limit sugar to only 5% of calories, then you'll see a reduction in prediabetes and diabetes by 50%. We've known this since the early 1980s, but the dietary guidelines during that time specifically said sugar does not cause diabetes," despite evidence to the contrary.

"Basically, the dietary guidelines were lying to us," DiNicolantonio said.

At the time of the NEJM review, Mark Hegsted was one of the nation's top nutritional scientists, he noted. "If someone with that much clout said sugar wasn't harmful, a lot of people are going to believe that person, at least until the '90s when we started demanding systematic reviews and meta-analyses."

Given the evidence, DiNicolantonio said, the NEJM should retract the original article. "These authors were literally paid. . . . It wasn't acknowledged that they were directly paid to write this paper," but what they wrote was "clearly influenced by who they were paid by," he said.

This study was supported by the UCSF Philip R Lee Institute for Health Policy Studies; a donation by the Hellmann Family Fund to the UCSF Center for Tobacco Control Research and Education; the UCSF School of Dentistry Department of Orofacial Sciences and Global Oral Health Program; the National Institute of Dental and Craniofacial Research; and the National Cancer Institute. The authors report no relevant financial relationships. Di Nicolantonio reports being the author of an upcoming book with bearing on dietary sugar and policy, serving as a frequent reviewer for several medical journals, and being on the editorial advisory board of several medical journals including the International Journal of Clinical Pharmacology & Toxicology, CIP Journal of Cardiology, and Progress in Cardiovascular Diseases. Nestle's salary from New York University supports her research, manuscript preparation, and website. She also earns royalties from books and honoraria and travel from lectures on subjects relevant to her commentary, she reports.

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