Before I tell you what that was, let’s examine an analogy. Not all that many years ago, textbooks on infectious diseases would have been entirely silent on the topic of peptic ulcer disease. When I began my medical training in the 1980s, everyone (more or less) still thought gastric ulcers resulted exclusively from over-production of stomach acid, related in part to diet, and in particular, stress. Medications such as aspirin and anti-inflammatories were known to inflame the stomach and increase susceptibility.

There was no awareness of an infectious etiology until the discovery in 1982 of the bacterium now called Helicobacter pylori, which led to a Nobel Prize in Medicine in 2005. Now, of course, all major textbooks on infectious disease address peptic ulcer- often with a chapter all its own (chapter 218 in this case). A modern textbook on infectious disease would be deficient, and we might say “unbalanced,” were it to omit this topic.

So, too, for the environmental impact of dietary choices. Environmental degradation is the single greatest human health threat of our age, the Anthropocene.

The idea that environmental effects are health effects was novel at the start, just like the idea that peptic ulcers might be an infectious disease. Now, the former, just like the latter, is established fact.

Diet, of course, is not THE cause of our stark, dire environmental woes- but it is an important cause. What we eat at the scale of nearly 8 billion hungry Homo sapiens, and how we produce that food, has massive implications for greenhouse gas emissions, water utilization, soil viability, air quality, biodiversity, and more.

The ice in Iceland is melting, and diet is an important reason why. Island nations are sinking, and diet is an important reason why. The Amazon is ablaze, as has been the rain forest in Borneo– and diet is an important reason why. The permafrost is disappearing, and diet is an important reason why. We are ever more prone to floods and fires and droughts, and diet is part of the explanation. This planet’s greatest native treasure, its stunning biodiversity, is desperately imperiled- and in part because we are eating it to death.

All of these, and myriad other environmental degradations, translate very directly into adverse human health effects. Ecosystem disruptions are responsible for emerging infections, from anaplasmosis to Zika. The profound influence of social determinants of health is epidemiologic gospel, and these determinants are devastated among the increasing ranks of climate refugees. Declining air quality means increasing rates of respiratory disease. Fires, floods, tornadoes, and hurricanes are lethal in the most obvious of ways.

Any number of such links might be enumerated, but the chain of causal reasoning leads only and always to the same fundamental conclusion: there are fewer and fewer, and ultimately no, healthy people on a ravaged planet.

Diet, and most particularly meat production and consumption, is a key contributor to that causal pathway.

The Atkins Diet, which begins with a ketogenic phase, has been adapted into a plant-based version that reconciles the dietary inclinations of those favoring “low carb” eating with kinder, gentler treatment of our planet and fellow creatures. A sustained ketogenic diet, however, is all but impossible in principle, and vanishingly unpopular in practice, without a substantial emphasis on meat. Part of the appeal now, as at the peak of Atkins’ uptake, is the implicit invitation to eat fatty meat dripping with butter. So, in practice, ketogenic dieting means more, not less, meat consumption. That, in turn, means a sicker, not healthier planet- and the fate of us planetary inhabitants follows.

There are no healthy people on a ruined planet. In 2019, peptic ulcers are an infectious disease. In 2019, the single most salient health effect of any dietary practice is what it contributes to the fate of Earth. We are benighted to fixate on the trajectory of our personal weight over 3 months or 6, while the weight of the world hangs in the balance.

My personal view of the ketogenic diet, informed by a lifetime immersed in the relevant evidence, is that it will disappoint its current disciples over time, as it has before.

That said, personal views and feelings are subordinate to the weight of scientific evidence. I have advocated my entire career for the hegemony of epidemiology over ideology. I practice that perspective, and have evolved my positions on many topics over the years in response to the evolving evidence.

To be sure that the evidence one knows is all the evidence there is requires a review of the science, and preferably, a review both comprehensive, and systematic. Such a review of the health effects of the ketogenic diet has been commissioned by the True Health Initiativeand should illuminate the topic after the requisite months of work by a diverse group of scientists.

But we need not wait for that to rue the environmental implications.

The omission of planetary health effects, of course, runs much deeper than Mr. O’Connor’s journalism- it is a cultural blind spot. I was privileged to give keynote addresses for Pri-Medthroughout the country last year. In each city, I told my audiences of thousands of primary care practitioners that one could not truly be a “health” professional in 2019 and not advocate fiercely, and frequently, for the health of the planet. Colleagues lined up to thank me for public permission to address the very topic keeping them awake at night, but which they doubted belonged to their professional purview. Yes, it does; there are no healthy people on a ruined planet.

Planetary health effects are human health effects, and ostensibly the most profound of all. For the health effects of keto, or any diet, to be weighed and measured adequately at this juncture in history, it is not enough to consider only the temporary fluctuations in the weight of people, and the attendant flux in biomarkers. The literal weight of the world- its glaciers and aquifers; sea levels and soil quality; average temperatures and food production; its rain forests and permafrost; its biodiversity and extinction rate- must be placed on the scales. Nowhere in all the vast medical literature is there a single example of health in a species without a viable planet to call its own.

So, no, the coverage of keto was not balanced. What could be more unbalanced than sleepwalking off a cliff? The blunt reality of the landing- is the gravest health effect of all.

https://www.linkedin.com/pulse/keto-weight-world-david-l-katz-md-mph-facpm-facp-faclm/