IntroductionLactose intolerance is a bodies inability to digest certain components of dairy products and appears to be becoming more prevalent in some societies.Lactose intolerance is a bodies inability to digest certain components of dairy products such as the carbohydrate, lactose. Lactose is mainly found in yogurt, ice-cream, cheese and other products containing milk. This is due to lactase be very prominent in milk. Symptoms for lactose intolerance are stomach pain or cramps after 30 minutes of consuming, gas or rumbling sounds coming from the stomach. Although I will go into detail further on in the essay, it’s worth mentioning it’s high occurrence in eastern asia and low occurrence in southern europe.What is Lactase?When we are around 0-24 (2 years) months, our bodies produce an enzyme. This enzyme is called lactase. Lactase targets a carbohydrate called Lactose. Lactose is a sugar found in milk which cannot be absorbed. Lactase is produced in the brush border located in the small intestine but it is worth mentioning that it is actually produced by many organisms such as dogs, cats and almost every other mammals.Why are some people Lactose Intolerant?Lactose intolerance is found when a person has stopped producing Lactase. Approximately 65% of the world’s population are less tolerant to lactose after 5 years. This is due to humans, as a species, drinking milk after weaning. To prove that claim, it is very rare for a baby to be lactose intolerant because we were designed to drink milk as a baby, not as an adult. Grown cows don’t drink milk, grown pigs don’t drink milk and it is a common misconception that cats love milk. We are the only breed which drinks milk after weaning. Humans, along with any animal which has a weaning stage, aren’t designed to drink or consume products containing lactose, or lactose itself. Human consumption after weaningAnother subject to shine light on is the fact that, after weaning, humans drink the milk of cows. There are no other species which drink the milk of a different animal. In fact, I myself had never drunk breast milk after weaning but I drink the milk of a cow almost every day. This is because I would feel uncomfortable drinking milk that has come from another human’s body yet I don’t feel uncomfortable drinking the milk of a completely different species. I suppose humans are not designed to drink milk after weaning, let alone their own species milk. Cows milk was designed for calves. Humans milk was designed for babies. We ignore both of these statements and that could be what leads to so many people becoming lactose intolerant. Another notableAreas of high and low occurrence of Lactose IntoleranceThere are some nations more affected by Lactose Intolerance than others. Just take Sweden & China. 92.3% of the chinese are lactose intolerant, whilst only 4% of the swedish are. Infact, east asians are very lactose intolerant but central-eastern african and southern europeans are very lactose persistent (which means the opposite to intolerant.) That brings us onto the next topic.The evolution of lactose intoleranceScientist were puzzled on why certain people were lactose persistent and some aren’t, until Joe Terwilliger from Columbia University was able to zoom into the Chromosome 2 DNA string. In Fact he zoomed in to a part of the lactase gene located in the Chromosome-2 which was likely to contain the gene mutation which leads to lactase persistence. After zooming in the research team noticed a big discovery. The lactase intolerance and the lactase persistence genes were the exactly the same apart from one base. They found the one base difference. A “C” in the place of a “T.” Why are some people Lactose Persistant?Although this discovery was a successful attempt to find out why lactose intolerance occurred there was one flaw. It barely existed in the maasai tribe. Infact, the genetic mutation barely existed in central-east africa. It turned out that the central-east africans had a completely different genetic mutation than the other europeans. Instead of a “C” in the place of a “T” there was a “G” in the place of a “C.” This discovery lead scientists to ask the question why. After looking at both areas historical and dietary past they have come to a conclusion. Both the southern europeans and the maasai tribe consume milk on a frequent basis and also historically both have drunk milk after weaning and on the other hand, China (an eastern asian region) only consumed 9.1 liters of milk per capita in 2011. Maybe through evolutionary advance they have developed a muttation making them less likely to develop lactose intolerance?Scientific solutions to prevent the symptoms of Lactose Intolerance?It does seem that ,as such a high percentage of the population are lactose intolerant there must be a simple solution and there is. Through biologically modifying the milk itself, scientist and milk manufacturers had the ability to implement exes lactase into the milk they were manufacturing so that, upon consumption, the lactase which was implemented into the milk would act as a replacement for the consumer’s bodies lactase which it has now stopped producing. So when the consumer (who is lactose intolerant) drinks the lactose-free milk they also consume small amounts of lactase, the milk goes through the normal cycle but because the consumer has consumed the extra lactase, it doesn’t affect them. Although modifying lactose contained in dairy product may be tampering with the way nature created itself, it still potentially benefits 65% of the population who are thought to have less tolerance against lactose after infancy. Basically, the body has stopped producing lactase so it is needed to consume extra lactase to stop getting the symptoms of being lactose intolerant. Although this method is quite common there is another method of cancelling the effects of lactose intolerance. It’s called lactase replacement product. It is where the lactose intolerant person takes drops or tablets containing lactase. The tablets are relatively cheap and gives the body lactase but like most medicine there are potential side effects. The most common of them are along the lines of stomach cramps and nausea however it is not clear if it is the pill itself or the pill not functioning properly.Summary In summary, Lactose Intolerance affects a lot of the population but when science is applied then we can cancel the symptoms. Although some methods can be argued that they are unethical due to side effects, they have changed some peoples life for the good and although not 65% of the world are officially lactose intolerant, 65% of the world are less tolerant than when they were being fed breast milk. So they’ve started to loose their lactase enzyme. Even though, I do try to make my BibliographyHendrickson, Kirstin. “How Is Lactose-Free Milk Made?” LIVESTRONG.COM, Leaf Group, 3 Oct. 2017, www.livestrong.com/article/337301-how-is-lactose-free-milk-made/. 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