Forty-four years ago my mother, Frances Moore Lappé, published “Diet for a Small Planet,” a book that dared to suggest human beings could survive, even thrive, on a plant-centered diet and that doing so would be good for our bodies and the planet. Part meatless cookbook, part treatise on the roots of hunger and the waste, inefficiency and injustice of diverting prime cropland to feed livestock rather than people, her book went on to sell more than 3 million copies.

At the time, the messages in her book were so threatening to the meat industry that the National Cattlemen’s Beef Association, the trade group for U.S. beef producers, hired a team of nutritionists to prove her vegetarian recipes were inedible. It’s hard to imagine now, seeing as you need only tune in to the daytime talk show “The Chew,” flip open Food & Wine or sidle up to a table at Alice Waters’ Chez Panisse restaurant in Berkeley, California, to realize plant-centered meals are everywhere — and devoured.

Last month, some four decades after my mom published that book, the scientific advisory committee for the federal nutrition guidelines, which inform everything from food stamps to school lunches, recommended for the first time that Americans choose a more plant-centered diet for both health and environmental reasons. The committee’s report states:

A diet higher in plant-based foods, such as vegetables, fruits, whole grains, legumes, nuts and seeds, and lower in calories and animal-based foods, is more health promoting and is associated with less environmental impact than is the current U.S. diet.

And, as the advisory committee notes, the average U.S. diet currently “has a larger environmental impact in terms of increased greenhouse gas emissions, land use, water use and energy use.” That’s in part because we eat more red meat and poultry per capita than anywhere else in the world, save Luxembourg.

Studies show that reducing red meat and poultry consumption is a key way to cut water use and greenhouse gas emissions. Beef is the main culprit: A 2014 study found that beef production in the United States requires 28 times as much land and produces five times as much greenhouse gas emissions as the average production of other livestock. And a 2012 comparative analysis (PDF) of water use across a wide variety of foods found beef was the most water intensive, with a water footprint per gram of protein six times as large as for legumes.