More of the same

It seems if you grow it, you can make milk out of it. But it comes at a cost to the environment.

Boston-based Walter Willett, professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health says plant-based milks are all made the same way: nuts, beans, or grains are ground into pulp, strained and combined with water.

He says plant-based milks are considered 'greener' than dairy and emit fewer greenhouse gases during production. However, growing some of these plants and making them into milk requires great quantities of water. Most plant-based milks are low-calorie. On average, though, these milk products cost more than dairy.