Council for Responsible Nutrition acknowledges error in its statement, but stands firm in its critique of SPORT study

15 Nov 2022 --- The US-based Council for Responsible Nutrition (CRN) recently issued a damning statement regarding an AstraZeneca-funded study which compared the cholesterol-lowering effects of six different supplements to the statin drug Rosuvastatin, claiming that the study was potentially biased. 

The accusation was based on CRN’s interpretation that the study was not double-blind and therefore lacks validity. Additionally, the organization holds that the selection of supplements used along with the timespan of the study may give people a false impression about the efficacy of supplements.

The organization now informs NutritionInsight that it made an error in its judgment of the study’s framework, which it now concedes was in fact double-blind, however, CRN maintains its original critiques regarding the supplements used and timespan, which it holds are of more importance than whether or not the scientists conducted their procedures correctly. “This limitation is minor compared to the major flaws that we identified with the study,” a representative says.

Dr. Andrea Wong, senior vice president of scientific and regulatory affairs at CRN, initially told us: “A limitation was the single-blind design of the study, meaning the subjects did not know what product they were receiving but the researchers did. Not having the study product blinded to the researchers increases the risk of bias.”

However, after being presented with a statement from Dr. Laffin in defense of the study, a representative for CRN told us that, “Dr. Wong admits we made an error about the blinding.”

When confronted with these statements and asked to comment on CRN’s other points of contention, Dr. Luke Laffin, co-director of the Center for Blood Pressure Disorders and the medical director of cardiac rehabilitation at Cleveland Clinic, told NutritionInsight, “I have no desire to engage with individuals or groups that comment without reading the actual study manuscript.”

Double-blind, but still blind?
A double-blind study is one in which neither the researchers nor the participants knows which participants are taking placebos, which are taking interventions and, in this case, which participants are taking which interventions. 

Dr. Laffin says that people should trust the experts and researchers conducting the science.This makes the study less likely to be affected by factors unrelated to the interventions being tested and ensures researchers and participants do not bias the results. 

Dr. Wong originally stated that researchers were not blind to which participants received the placebos, statins and supplements, likely leading to bias in the study. 

Moreover, CRN originally stated that the Supplements, Placebo or Rosuvastatin (SPORT) study out of the Cleveland Clinic in Cleveland, Ohio, US, was further flawed in that it used supplements that were either not known to have an effect on cholesterol and those that could were not tested long enough to show an effect. 

Not a retreat
Meanwhile, Dr. Laffin argues that this assertion is false and could only be made if the group did not properly read the study.

“Our manuscript clearly states that ‘Investigators were blinded to participant study group allocation,’” he says. 

He continues, quoting the text of the study: “‘Participants were not informed of study group allocation and supplements were repackaged into unlabeled bottles. However, given the various supplement pill regimens (different numbers of pills per day of assorted shapes and sizes), formal participant blinding was not undertaken.’”

Nevertheless, Dr. Wong states that the CRN’s other arguments against the study’s integrity are still valid. 

“Our overall response to the study stands,” she says. “Other healthcare practitioners we’ve consulted with agree with our viewpoint.”

Dr. Wong maintains her original argument regarding the supplements selected, noting that some of them “are not primarily marketed for cholesterol lowering,” and she states it is therefore still unclear why they were included.

Furthermore, she also defends her statements regarding the length and duration of the study, noting that “the benefits of many supplements are shown with consistent, long-term use.”Dr. Laffin says that people should trust the experts and researchers conducting the science.

“A lack of understanding”
Moreover, Dr. Wong contends that the study is misguided in its endeavors. 

“The study design reflects a lack of understanding of how nutrition and supplementation work to benefit health,” she argues. “Nutrients and other ingredients support health through consistent use over time.” 

“Further, they do not work in isolation – they should be combined with a balanced diet, regular exercise, and other healthy lifestyle choices,” she continues. “Statins have a real role in treating high cholesterol and this study reinforces the role.” 

“However, the study does not show that the supplements tested have no benefit for heart health,” Dr. Wong adds.

For his part, Dr. Laffin urges readers to trust the conclusions of experts and scientists. 

“I encourage individuals and medical providers to read the study and see the results of a rigorous, peer-reviewed, randomized clinical trial, conducted by experts in cardiovascular medicine and lipidology,” he concludes.

By William Bradford Nichols