The BMJ has issued two “clarifications” to an investigation it published last week that questioned whether the new U.S. dietary guidelines were evidence-based.
The article criticized several aspects of the new dietary guidelines, such as “deleting meat from the list of foods recommended as part of its healthy diets” — without, according to author Nina Teicholz, reviewing the scientific literature on meat. However, according to the clarification, that sentence should have specified “lean” meats.
After The BMJ‘s article appeared, an analysis on The Verge questioned whether Teicholz was guided by her own opinions. She’s the author of a book The Big Fat Surprise: Why Butter, Meat and Cheese Belong in a Healthy Diet. The Dietary Guidelines Advisory Committee also posted a lengthy “rapid response” — The BMJ‘s refined version of a comment section — to Teicholz’s article, saying it “strongly disagrees with many of the statements represented as facts.”
This afternoon, Rebecca Coombes, head of investigations and features at The BMJ, posted a response:
We are happy to clarify two aspects of Nina Teicholz’s article.
1) Deletion of meat: The article sought to report how the DGAC has dropped lean meat from the list of foods recommended for a healthy diet. Although lean meats are recommended in the 2010 guidelines, they no longer appear in the committee’s proposals for the updated 2015 guidelines.
The article says: “New proposals by the 2015 report include not only deleting meat from the list of foods recommended as part of its healthy diets, but also actively counselling reductions in ‘red and processed meats.’”
We accept that the article would have been clearer if it had used the phrase “deleting lean mean” [sic] rather than “deleting meat.”
2) Percentage of reviews conducted by the National Evidence Library: The article notes that the DGAC “did not use NEL reviews for more than 70% of the topics.” Because some of the topics did not require reviews of the scientific literature, the article would have been clearer had the next sentence specified that we were referring only to those that did. The numbers provided by the report are contradictory, but it appears that the portion of questions requiring a systematic review that did not receive one is 63%.
However, as The Verge reports, the guidelines actually say that “a healthy dietary pattern is…lower in red and processed meats,” and “additional strong evidence shows that it is not necessary to eliminate food groups or conform to a single dietary pattern to achieve healthy dietary patterns.” The guidelines also include a footnote that states “lean meats can be a part of a healthy dietary pattern.”
The BMJ investigation was “externally peer reviewed and fact checked,” according to a note at the bottom of the piece.
Yesterday, Coombes told us in an email that there were no plans to correct the article:
There are no plans for a correction. As with any of our articles, anybody possible errors that are brought to our attention will be checked and a correction issued if necessary.
She also told us yesterday that Teicholz would be posting a response today; we’re still waiting on that:
Nina Teicholz is posting a rapid response in answer to some of the critiques, chiefly the [Dietary Guidelines Advisory Committee]. You will also note the positive comments posted in response to the article.
We routinely ask authors to engage with the comments post-publication as you might expect.
This morning, Coombes clarified to The Verge where Teicholz’s conflict-of-interest was listed (it wasn’t on the pre-print of the piece that went out to journalists):
The BMJ did not list Nina Teicholz’s competing interests in the print version of the journal. This is in line with our routine policy to direct readers to the full, online version on thebmj.com. We have taken this position for reasons of space and readability. The contents page of The BMJ print journal clearly states: “Full versions with references and competing interests are on the thebmj.com.”
The BMJ is an online-first journal and we treat thebmj.com as the canonical version of the journal. The print version is a weekly digest of best and most relevant content for our UK readers.
The DGAC’s response takes issue with some bigger picture points in the investigation, such as:
In terms of the Scientific Reports findings, Ms Teicholz criticizes the Committee’s conclusions on saturated fat, red meat, salt, and added sugars and dietary carbohydrates and states that the report failed to “consider any evidence that contradicts the last 35 years of nutritional advice.”
These criticisms are unfounded and the conclusion reached is utterly untrue. For example, as it pertains to saturated fat, the Committee reviewed evidence from seven systematic reviews or meta-analyses published between January 2009 and August 2014 in peer-reviewed journals, which included RCTs and/or prospective cohort studies.
The DGAC comment concludes that,
In our opinion, Ms. Tiecholz’s [sic] article is woefully misleading and in many cases, factually incorrect. Its provenance is described as ‘commissioned’ and externally peer reviewed and fact checked. This statement is puzzling in its lack of detail and the validity of the statement on fact checking is doubtful.
We asked Teicholz for comment. She questioned why we’re writing about the story:
It’s not a retraction of any kind, so I’m not sure if it will be relevant for Retraction Watch…There is no dispute about my COI, nor are scientists petitioning BMJ. What is disputed is the substance of a piece, and this is really an issue for nutrition science journalists to cover.
According to The Verge author Arielle Duhaime-Ross (disclosure: a former New York University student of Retraction Watch co-founder Ivan Oransky‘s), the media’s take on the proposed guidelines could affect whether they are adopted. She writes on The Verge:
Every five years, the US government publishes a new set of dietary guidelines. The guidelines affect school lunches, food labelling, and scientific research — which is to say that their impact is very large. But the BMJ published an investigation that reads like pro-fat propaganda last week — and that means it will probably be used by the meat lobby to discredit the committee’s advice on lowering the consumption of red and processed meats. A Congressional hearing on the 2015 dietary guidelines is planned for October 7th.
The BMJ investigation was funded by the Laura and John Arnold Foundation, which also provides some of our funding.
Update 2/1/16 7:33 p.m. eastern: We’ve received a response from Teicholz, responding to specific allegations in the post:
1. Retraction Watch quotes the Dietary Guidelines expert committee (“DGAC”) as saying:
“These criticisms are unfounded and the conclusion reached is utterly untrue. For example, as it pertains to saturated fat, the Committee reviewed evidence from seven systematic reviews or meta-analyses published between January 2009 and August 2014 in peer-reviewed journals, which included RCTs and/or prospective cohort studies”
Response: For its review on saturated fats and heart disease, the committee did not adhere to the standard USDA procedure of consulting the Nutrition Evidence Library (NEL) to conduct a systematic review. Instead, the committee conducted its own review outside the NEL process. Whether this review was done in a systematic way is questionable.
2. Retraction Watch quotes the DGAC as saying: “In our opinion, Ms. Tiecholz’s [sic] article is woefully misleading and in many cases, factually incorrect. Its provenance is described as ‘commissioned’ and externally peer reviewed and fact checked. This statement is puzzling in its lack of detail and the validity of the statement on fact checking is doubtful.”
Response: The DGAC misspells my name. In addition, it provides no documentation of factually incorrect statements. This is an unsubstantiated allegation. The BMJ has stated that it commissioned my piece and had it externally peer reviewed as well as fact checked. I can confirm these facts. This allegation by the DGAC is also unverified.
3. “She also told us yesterday that Teicholz would be posting a response today; we’re still waiting on that.”
My Rapid Response was later posted here
4. Moreover, I would like to note that Retraction Watch’s exclusive reliance on The Verge for coverage of this important topic is a questionable choice, because of all the media coverage and various opinions expressed about the BMJ piece, the pieces by The Verge were by far the most highly critical. The reporter who wrote those pieces had no background in covering nutrition and had close access to the Dietary Guidelines committee as well as the USDA. Her coverage took the committee’s view entirely and did not attempt balance. By contrast, there was a great deal of coverage of the BMJ piece that was more balanced, by experienced reporters, in mainstream outlets, including the New Yorker, Time, Newsweek, and Yahoo Health. I collected most of the coverage and posted it here:http://thebigfatsurprise.com/media-coverage-bmj-article/
To provide balance to coverage by the Verge, I would offer the quote, in Cardiobrief, by Arne Astrup, a leading international nutrition expert: “the [dietary guidelines] committee seems to be completely dissociated from the top level scientific community, and unaware of the most updated evidence.”
Clarification 2/9/16 7:23 a.m. eastern: Teicholz requested we clarify her position as criticizing the committee for deleting meat as part of a healthy diet without — according to Teicholz — ever having reviewed the scientific literature on meat.
Like Retraction Watch? Consider making a tax-deductible contribution to support our growth. You can also follow us on Twitter, like us on Facebook, add us to your RSS reader, and sign up on our homepage for an email every time there’s a new post. Click here to review our Comments Policy.