Dairy is a fundamental part of our diets.  It’s one of the five major food groups.  It’s also terrible in terms of virtual water; a single liter (about a third of a gallon) of milk requires 1,000 liters of water to produce. 

After several years of living in Los Angeles, I’ve been introduced to many dairy replacements that don’t actually come from animals.  But are these an improvement over traditional cow’s milk?

Almond milk is a favorite amongst many vegans.  The milk is generally made of almonds, water, and a sweetener, such as honey.   A pound of almonds will produce 2 liters of almond milk, and you will use three cups water for each cup of almonds.  Each pound takes roughly 2,000 liters of water to produce, and that’s before you even account for the water used in the milk production.  Even though honey has no virtual water footprint, almond milk uses twice as much water to produce as cow’s milk.

Another common milk-less milk is soy milk.  Soy milk is made by blending re-hydrated soy beans with water.  A gallon of soy milk requires 208 gallons of water to produce.   That conversion holds for liters, as well, so our 208:1 ratio makes soy milk about five times more water-friendly than almond milk.  But can we do even better?

Another popular “milk” that doesn’t come from animals is hemp milk.  This is made of hemp seeds blended with water.  Cannabis seeds are ready to be harvested after the plant matures, which happens after a single plant has used 5-10 gallons of water in its life cycle.   One cup of hemp seeds will produce roughly 2.5 cups of hemp milk.  Seed output from a hemp plant can vary wildly, but let’s say a plant will produce 1/3 cup of seeds.  Converting all of this into liters for comparison, 114 liters of water are necessary to produce the amount of hemp need to make one liter of hemp milk.  Looks like we have a winner!