We are alive at a pivotal moment: For ourselves, for the Earth and for every animal on the planet. If we all are to survive, we must change the way we eat. Which sounds dire. But it is within our grasp. Think of it as a chance for a better world. A great and shared adventure. A journey to a place where we have long wanted to go, but until now lacked the means to reach. For many people, in many places, the shift is already underway: the move to a more plant-based diet. It is compassionate, it is hopeful, and, yes, it can be quite delicious.

The change begins with all of us. This summer. This week. Today. When you go to the grocery store, or open the refrigerator, or peruse a restaurant menu. The more you choose plants over animal products, the more animals you’ll spare from suffering, the healthier and better fed you’ll be and the more you’ll make possible a livable future.

We did not always know this, but now we do: The current system of intensive animal agriculture is unsustainable. And the switch to eating more plant-based foods must happen quickly. An article in Nature says that without big changes to current trends, the amount of food people require will reach levels “beyond the planetary boundaries that define a safe operating space for humanity.” An editorial in the medical journal The Lancet says we are approaching a day of reckoning. “What is a healthy amount of red or processed meat?” asks the writer. “It’s looking increasingly like the answer, for both the planet and the individual, is very little.”

Fortunately, there are plenty of other foods to eat, equally delectable. We have the teeth and guts of a species evolved to eat almost anything. For the majority of our history, most of us survived on little—if any—meat or milk or cheese or eggs. And we can do it again.

Josh Balk, vice president of Farm Animal Protection at the Humane Society of the United States, envisions people taking steps—some small, some large—toward eating plant-based. “It can be Meatless Monday, it can be vegan before 6 p.m. or other plans to reduce meat consumption,” he says. Think of it as, “ ‘I can make a difference. I can make a choice to support a system that is abusive and destructive or instead one that moves us toward a kinder, more merciful world.’ ”

Why now

It’s only since World War II—in the memory of generations still alive—that meat, egg and dairy consumption soared in the United States and other wealthy countries, giving rise to factory farms and the cage confinement of animals. Today, Americans eat more meat than anyone in the world—100 pounds per person every year, or three times the global average. If Americans ate plant-based diets, U.S. agriculture could feed about 350 million more people, says a paper in the Proceedings of the National Academy of Sciences. That’s because growing crops to feed to animals that people then eat is less efficient than growing crops that people directly consume. As animals eat, breathe, digest, move around and defecate, they use up—and lose—energy from food. In the case of beef, 96% of the protein fed to cattle is lost.

Environmental studies warn that large-scale meat and dairy production is pushing species to extinction as forests and grasslands where wildlife live are converted into acreage for growing fodder and grazing animals. “Livestock production is the single largest driver of habitat loss,” states one paper by researchers at Florida International and Oregon State universities.