In February 2014, David Katz MPH ’93, the director of the Yale School of Medicine’s Prevention Research Center, wrote two glowing online reviews of a science-fiction novel called reVision.

In his biweekly column in The Huffington Post, Katz lauded the book’s “lyrically beautiful writing,” comparing it to the work of a veritable “who’s who” of great writers, including Plato, John Milton and Charles Dickens. “I finished with a sense of illumination from a great source,” he concluded. “The most opportune comparison may be to a fine wine.” Katz had used similar language two days earlier in a five-star product review he posted on the book’s page on Amazon.

But Katz omitted a crucial detail from both reviews: the subject of his praise was his own self-published passion project, released two months earlier under the pseudonym Samhu Iyyam. In April 2014, after Katz revealed on Twitter that reVision was his own work, The Huffington Post updated his February review to indicate the true authorship of the book. As of 10:30 p.m. Tuesday night, the Amazon review remained unchanged.

In recent weeks, the Amazon and Huffington Post reviews have drawn significant criticism from doctors and pundits who disagree with Katz’s support for the United States Dietary Guidelines, a set of nutrition standards that help determine the contents of school lunches. Katz, an internationally renowned nutrition expert, told the News that the social-media backlash against the reviews is part of a smear campaign engineered by groups aiming to undermine the federal guidelines.

But Fred Brown, a spokesman for the Society of Professional Journalists, told the News the Huffington Post column was blatantly unethical, and the blogger, Peter Heimlich, who wrote about the Amazon review in late September and contacted the News shortly after, said he is not involved in the debate over the guidelines.

Katz said the reviews conveyed his honest opinion and that he concealed the true authorship of reVision because he preferred to keep his professional life separate from his fiction writing. He eventually decided to reveal he wrote the book in order to help it reach a wider audience, he said. Katz declined to answer specific questions about the reviews, including whether he told editors at The Huffington Post that he had written the novel before writing his column about reVision.

“I wrote a … review of my anonymously self-published fiction novel, and said what I really think about it — then disclosed that I wrote it,” Katz said. “There’s really a story there?”

Monica Lee, a communications officer for The Huffington Post, did not return numerous requests for comment.

But Brown said the Huffington Post review violated basic journalistic standards.

“It ain’t ethical,” Brown said. “You should not review something without revealing you wrote it.”

Katz, a staunch supporter of the Dietary Guidelines, has written nearly a dozen nonfiction books about nutrition. In 2009, three medical organizations — the American College of Physicians, the American College of Preventive Medicine and the Center for Science in the Public Interest — called for him to be named United States Surgeon General.

Over the past month and a half, the Amazon and Huffington Post reviews have come under intense scrutiny alongside an ongoing Internet debate over the preliminary report released earlier this year by the Dietary Guidelines Advisory Committee, the government task force responsible for drafting the guidelines. The preliminary report, which was released in February, is a rough sketch of revisions to the guidelines due to be announced later this year.

On Sept. 29, Jason Fung, a Toronto-based doctor who said he is skeptical of the guidelines, tweeted a link to the Huffington Post review: “Here’s @DrDavidKatz writing a glowing book review about a book he himself wrote under a pseudonym. What an ass.”

Fung said his tweet was a direct response to an opinion column written by Katz four days before, in which Katz accused health journalist Nina Teicholz, an outspoken critic of the guidelines, of making exaggerated claims designed to promote her bestselling book “The Big Fat Surprise.”

“He was trying to imply that she was just doing it to sell more books,” Fung told the News. “He’s just a huckster that goes around trying to promote his own book.”

In September, the British Medical Journal published a lengthy article by Teicholz that questioned the integrity of the Dietary Guidelines Advisory Committee. The piece has generated fierce debate in the medical community, pitting experts who consider the guidelines tired and out-of-date against a group of distinguished scientists with Katz at its head.

Parke Wilde, a Tufts professor who focuses on health policy, said the debate over the guidelines has begun to degenerate into name-calling. Wilde said there is a temptation on both sides to spend time attacking opponents rather than focusing on the substance of the argument.

Frank Hu, a member of the advisory committee, said opposition to the Dietary Guidelines has fueled the social-media furor around Katz’s reviews.

“[Katz] has been the most vocal, consistent, visible defender,” Hu said. “They are coming after David, presumably, because they feel his message may be harmful to their cause.”

Hu added that some opponents of the guidelines are affiliated with special-interest groups that have a financial stake in altering nutritional standards.

On Oct. 24, Katz addressed the controversy in another Huffington Post column, insisting that Internet bullies had dug up the reviews in an effort to discredit his nutritional advice.

But Heimlich, who contacted the News about the controversy, said he was unaware of the guidelines dispute.

“Instead of trying to change the subject, [Katz] should man up and explain what happened,” Heimlich said. Heimlich added that he has sent a formal complaint to Amazon asking that Katz’s product review be taken down.

Representatives from Amazon did not respond to repeated requests for comment. But the website’s official terms of service state the site has a “zero-tolerance policy for any review designed to mislead or manipulate customers.”

Chris Morran, a journalist who reports on Amazon for the Consumerist — a consumer-affairs site — said the company has worked hard to root out fake or misleading product reviews in the past.

“I doubt they’d look too kindly on someone reviewing their own thing,” Morran said. “You then start questioning other reviews, which makes the site look bad.”

Morran added that Amazon is trying to prove it is more reliable than its rivals in the increasingly competitive online marketplace.

Amazon sued more than 1,000 Internet vendors last month for offering to post bogus product reviews on the site.

DAVID YAFFE-BELLANY