Darwin and the Strange Consumption of Milk

I noticed, during my visits to East Asian countries, that buffets were devoid of milk and its products, and my attempts to find out the reason were unsuccessful until a few years ago. Milk, along with the cheese industry, is a key ingredient in a vast number of food, cosmetic, chemical, and industrial sectors, in addition to the production of yogurt, laban, butter, cream, condensed, powdered, and dried milk. It is also used in confectionery, chocolate, ice cream and frozen desserts, baked goods, white sauces, luxury soaps, plastics, dyes, button manufacturing, hairpins, eyeglass frames, and even in improving the soil for certain plants, as well as in dietary and sports supplements. Moreover, it is the most important source of calcium for bone building and preventing osteoporosis, especially for children, athletes, and the elderly. But why does milk consumption vary so significantly from one country to another? In Northern Europe, individuals consume hundreds of liters annually, whereas rates are very low in East Asia. The reasons are: 1. The difficulty of billions of people’s stomachs in tolerating lactose, the sugar found in milk. Through “genetic mutation,” it has been shown that humans are all born with “lactase enzyme,” which digests milk sugar and prevents its side effects, during infancy. This enzyme’s levels gradually decline after weaning. In European, North African, and Middle Eastern societies that historically relied on pastoralism, a genetic mutation (Darwinian theory) evolved, enabling the body to continue producing lactase throughout life. However, nearly 95% of East Asian populations still suffer from lactose intolerance, as the body stops producing lactase after weaning. 2. Cultural and dietary heritage, where milk and its derivatives form a cornerstone of daily cuisine. In East Asia, soy milk and other plant-based beverages have historically served as cultural alternatives. 3. Raising dairy cows requires green pastures and a temperate or cold, humid climate, which is not sufficiently available in Asian societies, or in societies that focused on herding camels and sheep rather than cattle, as generally occurred in Western societies. 4. Economic and industrial factors. Milk is highly perishable; thus, its fresh consumption requires advanced cooling, processing, and rapid transportation networks, which are not easily accessible in many countries, especially poorer ones. * * * Humans began consuming milk relatively late, despite their taste changing, even though they could not easily digest it. Furthermore, animals from which milk could be regularly obtained were not yet domesticated. When and why did this change occur? Neither the time nor the place where humans first began drinking cow’s milk is known, but there are some notable milestones. Twelve thousand years ago, humans in the mountainous regions surrounding present-day Turkey began transitioning from a hunter-gatherer lifestyle to agricultural societies. This required and was followed by the domestication of animals, starting with sheep and goats. Did adults also drink fresh cow’s milk? Based on human genetic patterns, researchers believe this likely occurred. Genetic mutations known as “lactase persistence” began to appear around 8,000 years ago, enabling adults to digest lactose; it is likely that these mutations emerged because some human groups were already consuming fresh milk. These mutations spread more rapidly in Northern Europe, where short growing seasons made milk a consistent and reliable source of calories, protein, and hydration.

Cattle, in particular, have produced larger quantities compared to other domesticated animals; moreover, milk in regions with cooler climates remained fresh and potable for longer periods than in warmer areas. Human groups that consumed large amounts of milk were generally taller and heavier, and individuals capable of digesting lactose were better able to survive during famines. Ahmed Al-Sarraf