With something as fundamental as diet and nutrition, can a committee of highly credentialed, well-respected experts get it all wrong? USDA’s latest Dietary Guidelines prove that they can.

Every five years, USDA and the Department of Health and Human Services issue revised dietary guidelines crafted by a Dietary Guidelines Advisory Committee of scientists and nutritional authorities, ostensibly to encourage Americans to eat healthier. That’s a noble ambition, and taken at face value, a positive initiative.

Lord knows we could all stand to eat a little healthier.

But the 2015 draft recently released (with the final version expected later this month) has expanded the focus to include an environmental assessment, and that’s where the recommendations run aground. The guidelines state that a diet higher in plant-based foods and lower in animal-based foods is “more health promoting and is associated with lesser environmental impact than is the current average U.S. diet.”

Wrong on both counts.

Is a diet of plant-based foods actually healthier for the environment? The committee members want consumers to eat more fruits, vegetables, nuts and grains. Sound advice — if it were offered in a vacuum. But it’s not.

You’d think that the illustrious members of the Dietary Committee would be cognizant of the fact that food doesn’t come from the supermarket or from a restaurant. It comes from farms and ranches, and the assumption that eating more fruits, vegetables, nuts and grains is simply a matter of making different choices as people push their shopping carts through the grocery store is outrageously naïve.

Where would those millions of tons of additional plant-based foods come from? Would farmers suddenly start growing produce instead of commodity crops? That would entail a tremendous restructuring of the farm economy, not to mention that fruits and nuts require years of cultivation before an orchard or berry farm becomes productive. Who funds that conversion? And what happens to the overall agricultural economy if thousands of ranchers, feeders and dairy farmers are phased out of business?

From a practical standpoint, wouldn’t a national dietary shift heavily favoring fruits and vegetables require even greater reliance on imports? No matter how organically committed farmers might be, you can’t grow beans and rice in the Midwest in January. Wouldn’t a serious shift from animal foods to produce potentially exacerbate the carbon footprint of the food supply chain, thus increasing the environmental impact?

Don’t bother searching for answers to those questions in the Dietary Guidelines because they were never addressed.

Now, had the committee opted for a massive program to get Americans to grow vegetables and fruits in their own household gardens, coupled with an equally robust effort to encourage canning and freezing of all that home-grown produce, it might be possible over time to lessen the environmental impact of our national diet.

But the committee is composed of scientists, professors, researchers, people who don’t get their hands dirty and who can’t be bothered with grassroots programming. They’re too wrapped up espousing lofty principles that are supposed to trigger the “proper” behavior among the rest of us.

But dig into any vegetarian dietary plan, and you’ll find that in order to provide the proper complement of protein and other macronutrients, people have to consume lots of soy protein in the form of highly processed products to accompany all that store-bought, out-of-season produce jet-freighted in from more tropical climates. You don’t have to go too far back in history to when it was impossible to survive — much less thrive — on a meat-free diet.

The only reason it’s become a viable option is because we now have processing technology and industrial-scale agriculture supported by the modern abundance of fossil fuel energy. Yes, we could go back to living like medieval peasants on a diet of mostly starch with some added produce and legumes. That would reduce our collective environmental impact. But you can bet that the member of the Dietary Guidelines Advisory Committee would be the last ones in line to sign up for that kind of dietary regimen.

A self-defeating argument

All that said, I don’t like the way that the meat industry has reacted to these latest draft guidelines. In most media accounts, the industry is depicted as arguing that an environmental agenda has no place in developing a blueprint for healthy lifestyles.

That’s not true. The environmental impact of food production is hugely important, and industry ought to be making the case that raising livestock can be as efficient in terms of producing nutritional value as growing grains or raising vegetables or maintaining orchards, all of which require arable land, irrigation water and significant infrastructure for harvesting, shipping, processing and distribution.

Industry stakeholders have also noted that meat and poultry contain more protein per serving than legumes, grains, vegetables and nuts. That’s certainly true, but a debate over the relative nutritional value of animal food always ends up with talking points emphasizing the merits of “lean meat.”

That presumes that both the fat that’s not consumed somehow disappears from the food supply. When fat is skimmed from non-fat milk, when skins are stripped off boneless poultry and when from deli meats are formulated with mostly lean muscle and binders, the fat that’s been removed doesn’t just evaporate. It ends up being added to ground meats, sausage products, hot dogs, meat snacks and other products.

When the official industry position is obsessed with promoting fresh, lean meat, it unintentionally justifies the demonization of processed meats and with it the condemnation of saturated fat as a nutritional villain to be avoided by anyone seeking a healthier diet.

Or a healthier planet, apparently.

Both positions are wrongheaded and ultimately destructive of industry’s interests.

The opinions expressed in this commentary are solely those of Dan Murphy, a veteran food-industry journalist and commentator.