Cow's milk naturally contains significantly more calcium than almond milk. Nonfortified almond milk has only 2 milligrams of calcium per serving, whereas cow's milk has roughly 200 milligrams in an 8-ounce serving.
Generally, almond milk, along with other milk alternatives such as soy, rice and coconut milk, are fortified with calcium and vitamin D to make them more nutritious. The popularity of almond milk has, as of 2014, risen considerably. Bovine milk, however, still commands a 90 percent share of the milk market over the alternatives. Almond milk is a water-intensive product; it takes over a gallon of water to produce a single almond.