Dairy farming seems to have been invented in Central Europe around 8,000 years ago. Many people in Europe have used sheep and goat milk since then to make cheese and yogurt. Most adult humans worldwide cannot drink fresh milk without getting sick.
A genetic mutation that allows adult humans to drink fresh milk without getting sick is believed to have appeared in Central Europe about 7,500 years ago. The mutation is thought to have allowed the spread of dairy farming throughout Europe. Dairy cattle were farmed by Germanic and Celtic peoples, who consumed fresh milk in large quantities. Milk is thought to be a good source of calories, protein and calcium.