NUPPRE

Industry-funded research sought to discredit links between sugar and heart disease—more than half a century ago.. 

The food industry has funded research in an effort to influence nutrition science and health policy for more than half a century, new research out Monday has found.

It’s no secret that industry funds such efforts today: An investigation in June, for example, showed how the National Confectioners Association worked with a nutrition professor at Louisiana State University to conclude that kids who eat sugar are thinner than those who don’t.

An article by University of California-San Francisco researchers, published Monday in JAMA Internal Medicine, shows how far back such efforts go: In 1965, the Sugar Research Foundation, the precursor to today’s Sugar Association, paid Harvard scientists to discredit a link now widely accepted among scientists—that consuming sugar can raise the risk of cardiovascular disease. Instead, the industry and the Harvard scientists pinned the blame squarely, and only, on saturated fat. 

By July 1965, after more research supporting the link had been published, SRF’s research director John Hickson was knocking on Harvard’s door, looking for scientists to refute the findings.

He found them.

That summer, Fredrick Stare, chair of the nutrition department in Harvard’s School of Public Health and by then also an ad hoc member of SRF’s scientific advisory board, began overseeing two Harvard colleagues in what was dubbed Project 226.

A few days before submitting the draft of their review for publication, they sent it to Hickson, who was pleased. “Let me assure you this is quite what we had in mind and we look forward to its appearance in print,” he wrote.

In 1967, their two-part review appeared in the New England Journal of Medicine. It concluded that there was “no doubt” that to prevent coronary heart disease, the only dietary precaution to take was to reduce consumption of cholesterol and saturated fat. In other words: Don’t worry about sugar.

To make their point, the Harvard researchers found fault with each individual study linking sugar to coronary heart disease, instead of focusing on the consistency of the findings across them all. One study, they said, should be discounted because it used greater doses of sucrose than found in a typical American diet. Another had found that substituting legumes for sugar led to major improvements in serum cholesterol levels—but the Harvard scientists argued such a move wasn’t feasible. They discounted studies for using fructose or glucose instead of sucrose, or using rats instead of humans.

At the same time, they were much less critical of studies linking heart disease to other dietary factors. The lack of evidence confirming links between dietary cholesterol and saturated fat and elevated serum cholesterol levels was unimportant, they said.

It’s not that the studies implicating sugar were perfect, said Cristin Kearns, who led the research for the JAMA Internal Medicine. It’s that, compared to those implicating fat, they were measured with a different yardstick.

“It is always appropriate to question the validity of individual studies,” Kearns said in an email. “However, the authors applied a different standard when they critiqued the studies linking sugar to CHD than they did to the studies implicating saturated fat and to those indicating that polyunsaturated fats could prevent CHD. The authors did not critically evaluate those studies. In fact, the authors overstated the consistency and quality of those studies.”

In a commentary accompanying the JAMA Internal Medicine article, Marion Nestle, a nutrition and public health professor at New York University and the author of Food Politics: How the Food Industry Influences Nutrition and Health, called the findings a “smoking gun” showing how those who fund research can heavily influence its findings.

The 1967 two-part review, she noted, had listed funding from the Nutrition Foundation but hadn’t noted that it was supported by the food industry or the SRF specifically.

In a statement Monday, the Sugar Association said that “the Sugar Research Foundation should have exercised greater transparency” but that it “is challenging for us to comment on events that allegedly occurred 60 years ago, and on documents we have never seen.” It also called it a “disservice that industry-funded research is branded as tainted.”

Walter Willett, the nutrition department chair at Harvard’s School of Public Health, said in a statement Monday that conflict-of-interest standards have changed significantly since the 1960s. He said the JAMA article offered a “useful warning that industry funding is a concern in research as it may bias what is published” and noted that Congress has allocated less and less funding for the past decade.

Willett also defended the Harvard scientists’ 1967 review, saying he agree with their “conclusion that there was not sufficient evidence to say that sugar was a causal factor in coronary heart disease risk.” But, he added, “given the data we have today, we have shown the refined carbohydrates and especially sugar-sweetened beverages are risk factors for cardiovascular disease, but that the type of dietary fat is also very important.”

But the emphasis on saturated fat over sugar, as illustrated in the Harvard scientists’ 1967 review, would have serious implications for dietary advice on heart health for decades to come, Nestle wrote in her commentary accompanying the JAMA article.

“For decades following the funded review,” she wrote, “scientists and dietary guidelines focused on reducing saturated fat as the primary strategy for coronary heart disease prevention.” Advice to eat sugar only in moderation was usually linked only to preventing tooth decay.

In 1980, when the first U.S. government dietary guidelines were published, the advice focused on reducing total fat, saturated fat and dietary cholesterol for coronary heart disease prevention. (In 1977, the federal government had originally proposed advising cutting back on the specific foods with dietary cholesterol and saturated fat—eggs, dairy, and meat—but thanks to industry lobbying, that didn’t happen, either.)

Nestle and Kearns both called for more independent research—but according to Nestle, that solution might not be simple.

“I, for example, have been told repeatedly that since I wrote Food Politics, I am ineligible to serve on federal advisory committees because I am too biased. What this tells me is that people who on principle refuse to take food industry funding are excluded from the candidate pool,” Nestle said in an email. “But people who do take industry funding are considered acceptable as long as they disclose their financial ties appropriately which, unfortunately, many do not.”

Watch Next: Confused About What to Eat? You’re Not Alone. 

Autor: Deena Shanker @deenashanker

Fonte: Bloomberg