This essay is from "(In)Tolerance Of Milk In Humans". Anti Essays. 6 May. 2012
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Although modern-day humans have existed for what seems like a second in the evolutionary timetable, it is amazing to think that lactose tolerance has only existed for ~7,000 years at best. Most Americans regard lactose as being very crucial in their well-beings and work hard to incorporate lactose intake into their diets; this is the same lactose that is absent in the diets of millions upon millions of people around the world; this isn’t true because lactose doesn’t cater to those people’s tastes, but rather because lactose isn’t tolerated amongst all those populations.
Most of the world is lactose intolerant, meaning that they do not have lactase [a milk-digesting enzyme] in their small intestines. Coupled with the fact that up until recently, [in biological time], humans were nomadic hunter-gatherers means that domesticating animals and drinking their milk was simply a waste of time for most populations around the world. Those who do have lactase in their systems, though, owe this to the fact that their lineage is likely to be prominently pastoral. The real reason behind the world’s lactose intolerance is owed to the fact that the weaning process, which typically occurs at about the age of 5, causes the small intestine to refrain from creating any lactase; therefore, as adults, it becomes uncomfortable for those people to consume any lactose, even in small dosages. The reason for lactose intolerance is attributed to more than just weaning, for most of the diets of people in a great part of the world consisted of meat and grains as opposed to milk, cheeses, and other dairy products.