Lactose and Lactase Essay Example
Lactose is an essential element and the source of protein for babies and children. However, in the course of the development, individuals steadily lose their ability to digest milk from infancy to their adult life. As a result, they become lactose intolerant. On the other hand, there are people, who remain tolerant to lactose and keep consuming milk throughout their adult life on the regular basis. In such a way, the question concerning reasons of such a difference between people arises. Researchers basically agree that the major reason for the difference in the tolerance of individuals to lactose is the result of the evolution. However, the further studies in this field are essential and they will help to find out the major causes of the difference in the tolerance of individuals in relation to lactose. In such a situation, the analysis of possible reasons for the difference in lactose difference can help to find out reasons why some people can digest milk successfully throughout their adult life, while others abandon the lactose tolerance after their infancy.Lactose and Lactase Essay Example
The milk consumption is natural for humans as well as for other mammals. At the same time, other mammals normally stop digesting milk and become intolerant to milk. In this regard, the tolerance of people to milk and lactose is rather the exception than a norm for mammals. The development of the tolerance to milk turns out to be unnatural for mammals.
On the other hand, humans as well as other mammals are naturally predisposed to the digestion of milk and are lactose tolerant at the beginning of their life at least since milk is the only source of nutrition. In fact, milk is the only source of nutrition for mammals in the natural environment. In this respect, the development of the tolerance to lactose turns out to be quite unusual at first glance because mammals and humans are born with the ability to digest milk.
However, the intolerance to lactose is strange just at first glance. In this regard, it is necessary to take into consideration the natural need of humans as well as other mammals in milk. For instance, humans need milk as the main source of nutrition for about half a year. In some cases, they need milk longer and may rely on breast feeding for the first and second years of life, while, in some rare cases, even longer. At the same time, starting from the first half year of life, humans start consuming other products except or along with milk. In other words, the vital need of humans in milk decreases and steadily fades away.Lactose and Lactase Essay Example
On the other hand, infants start consuming other products but milk. Moreover, other products steadily replace milk as the main source of nutrition for infants. In such a way, the need of humans in milk steadily decreases, while the need in processing and digesting other products emerges. Therefore, some researchers (Kretchmer, 72) suggest that humans tend to shift their digestive habits toward the digestion of other products than milk. As a result, they steadily lose the tolerance to milk and lactose because they do not need to digest lactose. In such a way, the steady decline of the tolerance to lactose occurs in the natural way. In this regard, researchers (Bersaglier, 1119) point out that some proteins and other nutritional elements required for humans in their adult life become dominating over the digestion of lactose and the tolerance to lactose decreases. Eventually, as individuals reach adulthood, they become intolerant to lactose.
In fact, such explanation of the development of lactose intolerance seems to be reasonable. Such a view on the milk digestion by humans offers a reasonable and logical explanation of the shift from lactose tolerance to lactose intolerance. However, there remains the major question which puts under a question the validity of the explanation given above. To put it more precisely, the question is as follows: if humans shift to lactose intolerance because they do not need to consume and digest milk as the main source of nutrition and steadily develop lactose intolerance, then why do some people preserve lactose tolerance?
To respond to this question, it is also possible to refer to mammals to compare whether humans are unique in this regard. Researches dedicated to this problem (Naim, et al., 430) reveal the fact that basically humans are rather unique in their lactose tolerance. This is why applying the same approach to the analysis of understanding of lactose tolerance as was applied to lactose intolerance brings quite the contrary results that means that the comparison of humans to other mammals is an efficient approach to the study of reasons for lactose tolerance or intolerance. In other words, the comparison of humans to mammas in their lactose tolerance is incorrect because of the difference in the lactose tolerance of humans. To put it more precisely, the share of people, who remain tolerant to lactose it too high to be viewed as a mere deviation from the norm. Instead, the large number of humans that stay lactose tolerant is high that means that this is a normal trend for human to remain tolerant.
In such a situation, it is possible to refer to other possible explanations of the problem of lactose tolerance or intolerance. In this respect, it is possible to refer to studies that reveal the fact that lactose tolerance is the highest in Northern Europe while lactose intolerance is the highest in Africa, the main part of Asia and Latin America as well as some other parts of the world such as Greenland and others.Lactose and Lactase Essay Example
In such a context, it is possible to suggest two more reasons for the development of lactose tolerance or intolerance. One of possible reasons is the environmental conditions which may affect human ability to digest milk. For instance, the different diet of people living in North Europe and Central Africa could stimulate the development of lactose tolerance or intolerance. Such a difference may result in the development of specific food habits along with adaption of human body and digestive system to specificities of the nutrition of people living in the specific region of the world. For instance, people living in North Europe may need enzymes that digest milk, while people living in Africa do not need them because their nutrition is completely different and their body just stops producing the enzyme required for the milk digestion. As a result, people living in North Europe develop lactose tolerance, whereas people living in Central African develop milk intolerance.
Furthermore, the development of the lactose tolerance may be also the result of the different lifestyle of people or the impact of their genetics. In this regard, the latter is more probable, taking into consideration the fact that the white population of the world is the most lactose tolerant, whereas the population of Africa, Asia and Latin America is predominantly lactose intolerant. Remarkably the native population of Greenland which is also close to the native population of Latin America and Asia are also lactose intolerant, whereas Australia populated by people of European descent mainly are lactose tolerant. In such a way, it is obvious that the genetic factor could play an important part in the development of human tolerance to lactose or intolerance. However, to support this assumption, further scientific researches are needed and they may help to obtain the definite answer on the question whether there is the gene responsible for lactose tolerance or intolerance.Lactose and Lactase Essay Example
However, this assumption is highly probable taking into consideration the demographics of the population with lactose tolerance and intolerance. The clear distinction and division of the population on lactose tolerant and lactose intolerant reveals the high probability of the heredity as the key factor contributing to lactose tolerance or intolerance. In this respect, some studies conducted in this field (Naim, et al., 431) give implications that there is the correlation between genes and human ability to digest milk in adulthood. In fact, researchers (Naim, et al., 431) reveal common trends in milk tolerance of specific ethnic groups and similarities in the level of their lactose tolerance. However, the debate on reasons of lactose tolerance or intolerance is still open.
In such a context, the last question that may arise in the course of the study of lactose tolerance and intolerance is the question of consequences or impact of lactose tolerance or intolerance on human health. In this regard, numerous studies (Naim, et al., 431) conducted in this field reveal the fact that the consistent reduction of the consumption of milk and lactose intolerance does not cause any negative effects or health problems in humans. On the other hand, lactose tolerance has similar effects on human health, i.e. it does not have any negative effects on human health. As a result, whether people are lactose tolerant or intolerant it does not matter. What does matter is breastfeeding at the beginning of human life because it contributes consistently to the enhancement of the immune system of individuals and determines, to a significant extent, their immune system and health.Lactose and Lactase Essay Example
Thus, taking into account all above mentioned, it is important to place emphasis on the fact that lactose tolerance and lactose intolerance are widely-spread. Some people are lactose tolerant, while others are lactose intolerant. The difference is determined by unclear factors, among which genetic factors play probably the most important part. On the other hand, further researches in this field are needed to determine which factors have the most significant impact and determine lactose tolerance or intolerance. Anyway, whether individuals are lactose tolerant or intolerant, they still do not suffer any physical health problems because of their tolerance or intolerance.Lactose and Lactase Essay Example