It simply takes too much water to grow a steak. In a new report, leading water scientists say the human population would have to switch to an almost entirely vegetarian diet by 2050 to avoid catastrophic global food and water shortages.

"Producing food requires more water than any other human activity — and meat production is very water-intensive,"

It's a simple numbers game: Cattle, for example, consume a shocking 17 times more grain calories than they produce as meat calories