In a recent Newsweek op-ed published during the COP21 climate change summit in Paris, vegan actress and animal-rights activist Alicia Silverstone wrote that while global environmental consciousness is at an all-time high, a piece of the “global-warming puzzle”—namely consuming less meat and dairy—seems to be missing from the conversation. “Our rapidly growing dependence on animals as a food source is one of the greatest threats to the climate,” Silverstone wrote. Her piece explained how raising livestock is responsible for 18 percent of greenhouse gases, requires 2,000 gallons of water per pound of beef, and is one of the biggest perpetrators of deforestation. The actress pointed out that while halting climate change is a challenge, it is also an opportunity for improvement. “It turns out that just by changing the way we eat,” Silverstone says, “we can hugely improve the environment’s health.