Recently, an opinion piece ran in the Los Angeles Times telling the world (well, that portion of it that reads the LA Times) that the conclusions about diet reached by U.S. News & World Report in their annual rankings were all wrong. Entire industries thrive on the propagation of the myth that everything about nutrition, and the obesity that attends it when we get it wrong, is shrouded in mystery. Among those industries are the media, of which both USNWR and the LA Times are, of course, a part. As long as everyone is perennially caught up in the great mysteries of eating well and controlling weight, there is a next story to run, and a next.

Ironically, concurrent with the LA Times opinion piece was the latest entry in a NY Times series highlighting the willful propagation of obesity and chronic disease around the world. In this instance, the subject was Kenya; it has previously been Ghana, Mexico, and Brazil. Perhaps next it will be India.

The alleged “mystery” of obesity is entirely mythical, probably manufactured, aided, and abetted by the very agents of that obesity. How could we reliably produce obesity where it did not exist before, consistently and across cultures, with the products and practices of our lifestyle, and for the sake of profits — if the causes of obesity were even remotely mysterious?

We could not. We know exactly how to cause obesity, and are in the business of exporting it. We thus know exactly how to fix it, too. Money, not mystery, conspires against that effort.

The notion that we can so reliably “produce” obesity and attendant metabolic mayhem without clarity about the causes is, in a word, absurd. The analogy that comes to mind is the heat of a fire. The concurrence of flame and heat might just be coincidence, but the collective human experience has judged otherwise. We recognize that heat reliably results when we make a fire, and consider the two causally linked.

We might rationally do the same for the consistency with which obesity and chronic disease ensue whenever, and wherever we replace native lifestyles of routine movement and minimally processed, plant-food-predominant diets with labor displacing technology, hyper-processed foods, and shifts to ever more meat and dairy. As is, we manage to look at these flagrant and consistent patterns and come away “confused,” or something like it. It’s as if we kept our hand in the flame until it burned entirely off while wondering at the enigmatic linkage between fire and heat.

That, in my view, is what the LA Times opinion piece invites us to do. My recommendation is to leave the irony in the fire, but withdraw your hand.

We don’t need renegade geniuses, dietary iconoclasts, or nutritional contrarians to tell us what’s what about diet, weight, and health; just look around! Where entire populations eat food, not too much, mostly plants — they tend to live long and prosper. Where they start emulating us and eating more hyper-processed junk and replacing plant foods with animal foods, they get fat and sick — and devastate the environment into the bargain.

The fault of nutrition experts gone awry? No. Where expert advice from even a half-century ago was applied with any fidelity at all, the result was a greater than 80 percent fall in the rates of heart disease, and more than a 10-year rise, on average, in life expectancy. It’s only where advice to eat less saturated fat turned into processed cookies ; advice to eat less sugar turned into chemistry experiments; advice to eat whole grain cereals turned into sugary cereals Froot Loops; and advice to eat more nuts was interpreted to mean doughnuts — that said “advice” did, and does harm

As one of the judges, my opinion about the U.S. News & World Report rankings is that it doesn’t much matter whether they are entirely right, entirely wrong, or anywhere in between. In those places around the world where diet fosters vitality and weight control, rather than fomenting obesity and disease, populations are not reviewing rankings or waiting for annual epiphanies at the expense of last year’s understanding. Where diet does all it should to tender years to life and life to years, it’s the same year to year and generation to generation. It’s when we show up with our fads and fashions; our bonfire of competing opinions; our Frankenfoods and rankings — that all manner of metabolic mayhem ensues. Just ask the Kenyans, Mexicans, and Brazilians — and for that matter, the Indians and Chinese.

The truth about diet, weight, and health is stunningly simple, and on flagrant display. But that truth has enemies, who bury it effectively not so much in mud, as in money. In this, alas, as in so much else, follow the money, and the apparent mysteries readily dissipate.

Dr. David L. Katz;; is founder, True Health Initiative