After analyzing the diets of 16,000 Americans, researchers led by Diego Rose, professor of public health, found that preparing meals with a small carbon footprint is as simple as using less animal protein. “People whose diets had a lower carbon footprint were eating less red meat and dairy — which contribute to a larger share of greenhouse gas emissions and are high in saturated fat — and consuming more healthful foods like poultry, whole grains and plant-based proteins,” he said.