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When did people begin using milk from animals? Probably about the time they began domesticating animals – some 8,000 to 10,000 years ago. Meat was certainly the most important food first provided by domesticated animals. But the milk of cattle, goats, sheep, or other animals also became part of people's diets. As agriculture developed, milk and other dairy products, such as butter, cheese and yogurt, became more and more important in the diet of human beings. For many thousands of years, a large percentage of the population was engaged in agriculture. Families commonly kept a few goats, cows, or sheep on their farms to provide fresh milk and other dairy products. With the coming of the industrial age, however, fewer and fewer people made their living through agriculture. The production of milk and products made from milk slowly became an industry.