Back in the 1960s, a sugar industry executive wrote fat checks to a group of Harvard researchers so that they’d downplay the links between sugar and heart disease in a prominent medical journal—and the researchers did it, according to historical documents reported Monday in the journal JAMA Internal Medicine.

One of those Harvard researchers went on to become the head of nutrition at the United States Department of Agriculture, where he set the stage for the federal government’s current dietary guidelines. All in all, the corrupted researchers and skewed scientific literature successfully helped draw attention away from the health risks of sweets and shift the blame solely to fats—for nearly five decades. The low-fat, high-sugar diets that health experts subsequently encouraged are now seen as a main driver of the current obesity epidemic.

The bitter revelations come from archived documents from the Sugar Research Foundation (now the Sugar Association), dug up by researchers at the University of California, San Francisco. Their dive into the old, sour affair highlights both the perils of trusting industry-sponsored research to inform policy and the importance of requiring scientists to disclose conflicts of interest—something that didn’t become the norm until years later. Perhaps most strikingly, it spotlights the concerning power of the sugar industry.

“These findings, our analysis, and current Sugar Association criticisms of evidence linking sucrose to cardiovascular disease suggest the industry may have a long history of influencing federal policy,” the authors concluded.

In a statement also issued today, the Sugar Association acknowledged that it “should have exercised greater transparency in all of its research activities.” However, the trade-group went on to question the UCSF researchers’ motives in digging up the issue and reframing the past events to “conveniently align with the currently trending anti-sugar narrative.”

The association also chastised the journal for publishing the historical analysis, which it implied was insignificant and sensationalist. “Most concerning is the growing use of headline-baiting articles to trump quality scientific research—we’re disappointed to see a journal of JAMA’s stature being drawn into this trend,” the association wrote.

But scientists disagree with that take. In an accompanying editorial, nutrition professor Marion Nestle of New York University argued that “this 50-year-old incident may seem like ancient history, but it is quite relevant, not least because it answers some questions germane to our current era.”

Both Nestle and the UCSF authors note that prior to the sugar industry’s involvement, nutrition research had pegged both sugars and fats as culprits behind coronary heart disease. Studies in the 1950s and early 1960s found evidence that low-fat diets high in sugars could boost cholesterol levels. The sugar industry had taken note of this, according to the historic documents. In 1964, the vice president and director of research for the Sugar Research Foundation (SRF), John Hickson, proposed that the group “embark on a major program” to dispute the data as well as any “negative attitudes toward sugar.”

Project 226

According the documents, the SRF enlisted Fredrick Stare, then chair of Harvard’s Nutrition Department, as a member of the trade group’s advisory board. Stare then put the SRF in touch with D. Mark Hegsted and Robert McGandy, members of Stare’s department. Hegsted would later go on to be the head of nutrition at the USDA. (All three researchers as well as Hickson are no longer alive.)

By 1965, the SRF funded “Project 226,” which would have Hegsted and McGandy—supervised by Stare—write a literature review that downplayed sugars’ role in heart disease and shifted blame solely to saturated fat. In return the researchers received a total of $6,500—the 2016 equivalent of $48,900.

During the write-up, which wasn’t published until 1967, the SRF’s Hickson was in frequent contact with the researchers, asking to review drafts and reminding them of the SRF’s interests. In one response to Hickson, Harvard’s Hegsted wrote, “We are well aware of your particular interest in carbohydrate and will cover this as well as we can.” After several delays in the writing, Hegsted reported to Hickson that they had to “rework a section in rebuttal” every time a new study came out supporting a link between sugar and elevated cholesterol levels.

In her editorial, Nestle concluded that “the documents leave little doubt that the intent of the industry-funded review was to reach a foregone conclusion.”

Hegsted and McGandy’s article, published as a two-part review in New England Journal of Medicine (NEJM), cherry-picked data, discounted studies that disputed its conclusion, and overstated the consistency of data suggesting that fat was the primary driver of heart disease. In conclusion, the review stated that there was “no doubt” that the only way to dodge heart disease was to reduce saturated fat.

The review made no mention of funding from the sugar industry. (NEJM didn’t start requiring authors to list conflicts of interest until 1984.)

After the review, the sugar industry continued to fund research into heart disease and other health issues. By the 1980s, few scientists focused on the role of sugar in heart disease. The 1980 Dietary Guidelines for Americans emphasized curbing fats and dietary cholesterol to prevent heart disease.

Today, Nestle points out, “the balance has shifted to less concern about fat and much greater concern about sugars.” But, the story should act as a cautionary tale of the potential harms from industry-sponsored studies.

JAMA Internal Medicine, 2016. DOI: 10.1001/jamainternmed.2016.5394 (About DOIs).