This story is about new evidence that may diminish the importance of limiting animal fats in people’s diets to reduce risk of deaths from heart disease. A new group of researchers re-examined a 45-year-old randomized controlled study of 9,000 people who were put in two groups: one group replaced animal fats with corn oil in their diet, the other ate animal fats. The risk of death from heart attack was higher in the vegetable-oil group, even though certain markers of cholesterol in their blood did become lower.
The story does a good job of explaining the study’s design, and some of the complex issues surrounding dietary habits and heart disease. But this story falls short by not quantifying study elements: no numbers for cholesterol level changes, no numbers for changes in risk.
Diet appears to play a role in dozens of chronic diseases, including heart disease. Research that helps tease out which fats are truly better for people helps us further understand the issue, though it is complex and evolving. News coverage should not only be accurate, it should help readers understand how the latest study fits into the greater body of scientific knowledge.
Since this is about affordable and widely available cooking oils, this is N/A.
The story does not quantify. We are told the 45-year-old data showed a “lowering” of cholesterol for study participants who swapped animal fats for vegetable fats. But we aren’t given any numbers for by how much or even by what percentage.
In a similar shortcoming, one of the most counter-intuitive findings was dismissed.
“In fact, the study found that the lower the cholesterol, the greater the risk of death. But that’s a misleading association because a variety of illnesses can also cause drop in cholesterol, which is unrelated to diet.”
The story should have given us some numbers for that “greater risk.” Even if it is misleading, we are entitled to know the size of the risk found in the study.
The intervention in the study (eating more unsaturated fat) is unlikely to cause adverse side effects, risks, or complications, so we’re rating this N/A. The story did point out the surprising association between lower cholesterol levels and increased risk of death, though that could have been explained more clearly.
The story gives us information about both the old Minnesota study and the new British Medical Journal publication. We know the old study was randomized and included 9,000 people. At the end of the story, we also learn the study has “many” limitations and some of these are mentioned.
Ideally, the story would have specifically pointed out that the study population included only residents of nursing homes and mental health hospitals, which may affect generalization. Also, given that this is decades-old data, we’re wondering how researchers took that into account, and how it might have impacted the quality of evidence.
There was no disease mongering.
There don’t appear to be any conflicts of interest, and the story includes an independent source.
The story does a good job of talking about the complicated recommendations regarding diet, as well as medications, specifically statins.
The different oils are widely available; this is N/A.
The story explains that the novelty is not with any treatment or discovery but rather a novel statistical examination of old data.
The story does not appear to rely solely on a news release.