Pros and Cons Of Milk Elizabeth Horen Beloit College, Beloit, Wisconsin

1. Discussion: General Benefits and Harms: It is clear from the results section that there is a lot of contradictory information regarding the health benefits and harms of dairy. To start, it is clear that milk is a good source of nutrients. Milk provides large amounts of calcium, protein and vitamins such as vitamin D (USDA). Furthermore milk is a source of potassium so milk can also help regulate muscle contractions, including the heartbeat, and ensure that blood clotting happens normally (BBC). One study even showed that dairy consumption can lower one’s blood pressure (American journal of clinical nutrition). One non-peer-reviewed source states “Studies show possible links between low-fat milk consumption and reduced risk of arterial hypertension, coronary cancer, and obesity” (Wikipedia). That said the pasteurization process that American milk goes through undoes many of the health benefits listed above. Pasteurizing the milk causes many of the proteins and essential nutrients to be denatured and or destroyed in the process. First the pasteurization process turns lactose into beta-lactose (Armchair Science). Beta-lactose is more easily absorbed into the body causing people, especially children, to be hungry sooner after consumption. Pasteurization also makes part of the calcium in raw milk insoluble. The raw milk enzymes that allow humans to properly absorb calcium is destroyed (Armchair). Although the process of pasteurization undoes several milk benefits, pasteurizing raw milk is important. The pasteurization process kills harmful microorganisms and prevents food born disease. It is clear from the discussion above that milk provides as many essential nutrients, even though some of them are compromised in the pasteurization process. That said it is important to consider some other sources of these nutrients when deciding whether or not dairy should remain in the adult diet. For example calcium can be obtained from eating spinach and potassium can also be obtained from eating a banana. Since these nutrients can be obtained from other sources some researches felt that milk is not really a necessity (BBC). Whole Milk vs. Skim Milk: There are three types of milk commonly distributed in the United States: Whole milk, reduced-fat milk and skim milk. As mentioned above in the introduction these categories are designated based on the percentage of milk fat found in each type of milk. Whole milk has 4% milk fat while skim milk has 0% fat. It is clear from the percent of fat in whole milk that it is more likely to cause weight gain as compared to the skim milk which contains 0% milk fat. Although the lack of fat in the skim milk is a health benefit, removing all the fat also removes some beneficial nutrients. The most important of which are Conjugated Linoleic Acids (CLAs) and omega-3s. “Cows’ milk fat contains at least two dozen distinct “fatty acids”two critical fatty acids [are] Conjugated Linoleic Acids (CLAs) and Omega-3s. CLAs and Omega-3s are widely recognized as key “nutraceuticals” (Hardin). CLAs are important because they tell the body how, where and when to store fats. Without CLAs skim milk is missing a huge health benefit of milk. Reduced-fat milk is a good choice for this reason. Reduced-fat milk provided the best of both worlds. It is lower in fat content than whole milk but it still provides CLAs unlike the skim milk. Weight Gain and Loss: There is a lot of controversy and disagreement in regards to the relationship between dairy consumption and body mass. Some studies showed a weight gain correlated with dairy consumption while others found that calcium and dairy consumption lowered body mass. “Substantial evidence exists for an association between dietary calcium or dairy product intakes and lower body waist circumference”. The results of randomized clinical weight loss trials demonstrate predominantly that dairy products enhance weight and fat mass loss but the results for dietary calcium are contradictory. The number of conflicting results suggests that if there is an effect, multiple factors, such as total energy intake, protein amount and source, and or vitamin D status, any act synergistically to regulate energy balance to promote reduction or prevent gain of body fat� (Teengarden). As stated by Teengarden there is not definite correlation between dairy consumption and weight gain, thus weight gain or loss is not a essential factor to be considered when determining the health benefits and harms of dairy. Abstract: Due to the vast and influential dairy industry in The United States Americans consume 16 billion gallons of milk per year. Although Americas are encouraged to consume it is important to consider the health benefits and drawbacks of dairy. Milk is a well know source of nutrients including but not limited to calcium, potassium and protein. Additionally it has been shown to regulate muscles contractions and lower blood pressure. Though the benefits are alluring, the pasteurizing process that milk undergoes in The States counteracts many of the benefits. In order to evaluate the pros and cons of dairy consumption, I have reviewed several peer- reviewed articles and compiled the information so that others can make an informed decision about including dairy in their daily diets. Intro: As a child, everyone is told that milk is healthy because it provides calcium which makes strong and healthy bones. But what are the pros and cons to milk consumption beyond what we were told growing up. To begin answering this question, it is important to look at the milk industry in America and what types of milk are distributed within the United States. Milk is a huge industry in America with Americans consuming over six billion gallons of milk per year not including the ten billion gallons of milk used to produce cheese in the United States (ProCons). The famous “Got Milk” campaign encourages people of all ages to consume this allegedly highly nutritious beverage in large quantities. However there is controversy in the scientific community about the health benefits of milk after infancy. Humans are the only species that consume milk post infancy and studies have shown that the enzyme needed to digest milk and other dairy products is most prevalent when humans are born and slowly decreases with age (Wiki- milk). Furthermore, it is only within the last 1000 years that humans have integrated dairy into their diets after childhood. The real purpose of milk is to provide infant mammals with nutrients until they graduate to consuming real food. Despite this information dairy is highly integrated in cuisines all over the world, especially in Europe, North America and India (Wikipedia). Although milk is intended for infant nutrition, it does provide some health benefits to adults as well. Even in adulthood milk is a source of calcium, various proteins and many vitamins such as vitamin D (USDA). It has also been shown to help lower blood pressure and regulate muscle contractions (American Journal of Nutrition). While the benefits of milk are clear, adult milk consumption also has some drawbacks. Many believe that dairy consumption is linked to weight gain. Additionally many of the health drawbacks of dairy arise because of how milk is processed in America (Armchair Science and Kim). Most, if not all, dairy in the United States undergoes a process known as pasteurization. Pasteurization is a process in which milk is heated to a temperature of 145 ｰF to 150ｰ F for 30 minutes and then it is cooled to 55ｰ F (realmilk). The process is intended to reduce microbial growth in the milk but it also lessens the health benefits of milk by destroying many of the proteins and nutrients that exist in raw milk (Kim). There are three types of milk that are distributed in the United States: whole milk, reduced-fat (1% or 2%) milk and skim milk. These categories are designated by the fat content in the milk product. Whole milk is comprised of 4% milk fat, reduced-fat milk is usually 2% milk fat and skim milk is 0% milk fat (Ordman). Each category of milk presents its own advantages and disadvantages. My poster I documents the pros and cons of milk consumption so that others are able to make an informed decision as to whether or not they want to include milk and dairy in their everyday diet. Table 3: Milk Composition Analysis, per 100 grams Pros and Cons Of MilkElizabeth HorenBeloit College, Beloit, Wisconsin Wikipedia - Milk Method:In order to investigate the pros and cons of milk I have read and reviewed peer-reviewed articles on the subject. With a clear understanding of the pros and cons of dairy consumption I have reformatted the information in a way that is more accessible and easier for others to understand so that they can make their own decision in regards to milk and dairy in their diets. Results: Table 4 presents the major pros and cons of dairy consumption identified in the professional journals that I reviewed. Charts for the Introduction: Table 1: American Serving Sizes USDA Table 2: Dairy Products There is a great deal of discrepancy about the health benefits and drawback of pasteurized milk. Table 5 presents the pros and cons of pasteurizing milk according to the peer-reviewed articles I reviewed. Table 5: The pros and cons to Pasteurization Conclusion: While this poster is intended to allow individuals to make their own decisions about their dairy consumption, here is my advice on the matter. I recommend that people of all ages incorporate a moderate amount of milk in their diets. As shows above there are several health benefits and milk is a good sources of nutrients for individuals of all ages. Additionally, I recommend drinking reduced fat milk. The reduced fat milk lessons the potential for weight gain while still providing the benefits of the CLAs. In moderate amounts I think milk and dairy are an important part of the human diet. USDA • References: • 1. Health: Milk and Dairy products: BBC - http://www.bbc.co.uk/health/treatments/healthy_living/nutrition/healthy_dairy.shtml • 2. Kim, Ben. Is Milk Good for You: Is Dairy Good for You?. Health and Beyond. http://chetday.com/ismilkgoodforyou.htm • 3. Milk/Dairy/Dairy products/Pasteruization. Wikipedia. McGee, Harold (1984). "Milk and Dairy Products". On Food and Cooking: The Science and Lore of the Kitchen. New York: Charles Scribner's Sons. pp. 3–53. • 4. Raw Milk Vs. Pasteurized Milk. Armchair Science. April 1938. • 5. Rosell, Magdalena; Hakansson N Niclas; and Wolk, Alica. Association Between Dairy Food Consumption and Weight Change. American Journal of Clinical Nutrition. Vol 84. No 6, 1481-1488. December 2006. • 6. Teengardener, Dorothy. The Influence if Dairy Product Comsuption on Body Compostion. American Journal of Clinical Nutrition. December 2005. • 7. United States Department of Agriculture (USDA): www.usda.org