Doctors clash over keto’s heart risks—one accuses the other of manipulating data

By MDLinx staff

Published May 1, 2025

Key Takeaways

Industry Buzz

“The fact is, these lean people with high LDL on the keto diet developed plaque several times faster than metabolically healthy populations.” — Dr. Idrees Mughal, MBBS, MRes, DipIB
“This is the first prospective trial of its kind in a unique population often labeled ‘high-risk’ by traditional guidelines, raising important questions about how cardiovascular risk is assessed in the context of low-carb, high-fat diets.” — Dr. Nicholas Norwitz, PhD

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A new study by researcher Nicholas Norwitz, PhD, has been making waves, claiming the ketogenic diet doesn’t increase heart disease risk—even with sky-high LDL cholesterol levels.^[] But not everyone is buying into this optimistic view. Idrees Mughal, MBBS, MRes, DipIBLM, a cardiologist with a sharp eye for data manipulation, isn’t convinced. In fact, he’s calling out key flaws in the study that, according to him, could be a serious ethical issue—and he’s not holding back. Here’s the showdown: does the keto diet really pose no risk to heart health, or are we overlooking some glaring red flags?

The study: What Dr. Norwitz found

Dr. Norwitz’s study followed 100 lean, insulin-sensitive individuals on a ketogenic diet for one year. Despite their high LDL levels, which are traditionally linked to heart disease, the participants had “minimal progression” of coronary artery disease. Norwitz and his team also found that LDL and ApoB didn’t predict plaque progression—challenging the long-held belief that high LDL is a major driver of cardiovascular issues.^[]

“The findings are tremendously fascinating,” Dr. Norwitz says, emphasizing that his study shows LDL isn’t as much of a risk factor as we thought—at least not for people on a keto diet with low triglycerides and high HDL.

The problem with the study

Dr. Mughal, however, isn’t so sure. He argues that key data was left out of the published findings—data that, in his view, could drastically change the interpretation of the results. “Nick and his co-authors left key data out of this study, which is a huge ethical concern,” he asserts.

One of the biggest issues? The study’s primary outcome measure—how much coronary plaque had actually built up—wasn't included in the published results. “The study’s protocol said it would measure this, but they didn’t give us a figure,” Dr. Mughal explains. After pushing for more information, the study's lead author, Adrian Soto-Mota, eventually revealed on X (formerly, Twitter) that the keto group saw an 18.8mm³ increase in plaque over the course of the year.

Is that a lot? According to Dr. Mughal, it is. He compares it to other studies showing that the typical annual change in plaque volume for metabolically healthy people is just 4.9mm³. “The keto group had four times the plaque buildup. That’s not minimal,” Dr. Mughal argues.

Plaque progression and the LDL factor

But Dr. Mughal isn’t stopping there. He also calls out the study’s failure to properly assess the relationship between LDL and plaque progression. Dr. Norwitz claimed that LDL wasn’t linked to plaque buildup, but Dr. Mughal sees a problem with that conclusion.

“With an average LDL of 254mg/dL in the study group, you’re not going to see a relationship,” he says. “There’s no variability. It’s like trying to find a difference in lung cancer rates between people who smoke 50 versus 60 cigarettes a day.”

In Dr. Mughal’s view, the lack of a lower-LDL control group makes it impossible to draw meaningful conclusions about the role of LDL in plaque buildup. “Without that variability, you can’t detect a dose-response relationship,” he adds. “And that’s what’s so frustrating about this study.”

Data omission or misinterpretation?

For Dr. Mughal, this study is an example of data manipulation to fit a narrative. “The fact is, these lean people with high LDL on the keto diet developed plaque several times faster than metabolically healthy populations,” he concludes. “But instead of acknowledging that, they omit the primary data and spin the results to make it look like high LDL is fine.”

Conclusion:

Dr. Norwitz’s study offers a hopeful take on the ketogenic diet, suggesting it doesn’t increase heart disease risk despite high LDL levels. But Dr. Mughal’s critique raises significant concerns about data transparency and study design. For physicians, the takeaway is clear: while keto may have benefits, we need to take a closer look at the full picture before endorsing it as a heart-healthy option—especially when critical data is left out of the conversation.