Como a ciência é contraditória !
" Major studies suggesting a link between milk and prostate cancer have appeared in medical journals since the 1970s. Two of six cohort studies (research studies following groups of people over time) found increased risk with higher milk intakes. Five studies comparing cancer patients to healthy individuals found a similar association. One of these, conducted in northern Italy, found that frequent dairy consumption could increase risk by two and one-half times.
In 1997, the World Cancer Research Fund and the American Institute for Cancer Research concluded that dairy products should be considered a possible contributor to prostate cancer. And yet another research study came out in April 2000 pointing to a link between dairy and prostate cancer: Harvard's Physicians' Health Study followed 20,885 men for 11 years, finding that having two and one-half dairy servings each day boosted prostate cancer risk by 34 percent, compared to having less than one-half serving daily. Researchers are looking, not only at whether milk increases cancer risk, but how. The answer, apparently, is in the way milk affects a man's hormones. Dairy products boost the amount of insulin-like growth factor (IGF-I) in the blood. In turn, IGF-I promotes cancer cell growth.3-5 A small amount is normally in the bloodstream, but several recent studies have linked increased IGF-I levels to prostate cancer and possibly to breast cancer as well."
http://www.physicians-background.com/pro.html
"Cornell researchers have found a way to boost what may be whole milk's natural cancer-fighting ability. By making simple changes in the cow's feed, they have substantially increased the amount of conjugated lineoic acid (CLA) -- a cancer-fighting compound -- in the milk.
A number of laboratory studies (not at Cornell) have shown that CLA suppresses carcinogens and inhibits proliferation of colon, prostate, ovarian, breast cancers and leukemia. While none of these studies has involved humans, laboratory research indicates that CLA, even in extremely low dietary concentrations (for example, 0.05 percent), inhibits carcinogenesis.
"Most dietary substances exhibiting anti-carcinogenic activity are of plant origin and are only present at trace levels," said Dale Bauman, Cornell professor of animal science who led the work. "However, CLA is found almost exclusively in animal products and is among the most potent of all naturally occurring anti-carcinogens."
Bauman and Miriam L. Kelly, Cornell graduate student in Bauman's lab, from Tyrone, Pa., were presenting their findings, "Conjugated Lineoic Acid: A Potent Anti-carcinogen Found in Milk Fat," on Wednesday at the Cornell Nutrition Conference for Feed Manufacturers in Rochester.
The research was funded by the Northeast Dairy Food Research Center, located at Cornell.
Thanks to the cow's digestive system, humans may benefit from drinking milk with increased CLA levels. Dietary fats, such as corn oil, in ruminants are released by microbes in the rumen, the first stomach chamber of four. Newly freed unsaturated fatty acids then undergo biohydrogenation, which combines the unsaturated fats with hydrogen, thanks to rumen bacteria in the later stage of digestion.
The result: With higher levels of unsaturated fats in the feed, the cow makes milk with increased levels of CLA.
"It's clear that dietary and management practices used by dairy producers are resulting in a rumen environment in which biohydrogenation of fatty acids varies so that higher levels of CLA occur," Bauman said. In collaboration with scientists from the University of Idaho, he set out to find out why.
The Cornell research shows a dramatic CLA increase when the cow's diet contains unsaturated fats, such as those contained in corn oil. For example, when only 3 percent dietary fat was fed, only 2 milligrams of CLA per gram of milk fat were found. But when unsaturated fats were doubled, researchers found 4.5 milligrams of CLA per gram of milk fat. When 7.2 percent unsaturated fat was fed, the cow produced 6.9 milligrams of CLA per gram of milk fat.
"The potential exists to identify dietary and management conditions that would increase the CLA concentrations in dairy products," Bauman said. "The novel part of all this is that we're using our knowledge of the dairy cow's digestive and metabolic system to design ruminant diets and practices that enhance CLA levels in milk.
"Milk now provides high-quality protein, energy, calcium, as well as a variety of vitamins and minerals for humans," he said. "This brings an exciting twist to the concept of redesigning foods. If milk is high in CLA, it may provide even greater health benefits: anti-carcinogenic capabilities.""
http://www.news.cornell.edu/chronicle/9 ... fight.html
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" It is a documented fact that consumption of dairy products can lead to the development of atherosclerosis, heart attack and strokes , and that high fat dairy products contain unsafe levels of environmental contaminants, including pesticide residues, antibiotics and estrogen steroids.
Milk consumption does not protect against fractures, according to new data from the Harvard Nurses Study. The study recruited a group of 77,761 women who were between 34 and 59 years of age when the study began in 1980, and followed them for the next 12 years. Those who drank three or more glasses of milk per day that is promoted by the Dairy industry had no reduction at all in the risk of hip or arm fractures compared to those women who did not consume any dairy products.
In fact, but not surprisingly, the fracture rates were higher for those who consumed three plus servings (8 ounces per serving), compared to those who did not drink milk. The findings resonate with international comparisons that show that fracture rates in Scandinavia, England, Canada, Denmark and other area where dairy consumption takes place is significantly higher than those countries were dairy consumption does not take place (Pacific Rim Nations, Africa, China).
The differences are the result of two other factors. First, in international studies, genetics play a role, with white women at higher risk than other groups. Second, other animal proteins greatly increase calcium loss via the kidney.
Cow's milk contains "antibiotics (up to 84 different at last count), pesticides, chemicals, hormones(rBGH), blood, white cells (pus)(1/30 of every ounce), and bacteria from mastitis (udder infection)" which the USDA and FDA either do not test for (they do test for 4 of the up to 84 anti-biotics used), or which they allow to be present in unacceptably high levels.
Various studies found "significant positive correlations" between milk intake and lung and ovarian cancers, leukemia, and Crohn's disease. And, possibly, lung and prostrate cancers , Dr. Kradjian notes, but with reservations: "the weight of evidence" suggests it's
the animal fat in milk which triggers the growth of cancer cells. This implies that meat is equally damaging. "At least half of human adults" are lactose intolerant, which offers proof, according to Dr. Kradjian, that "cow's milk was never intended for human consumption." Milk consumption does not protect women from osteoporosis; in fact, it may cause it. The body withdraws calcium from the bones to neutralize the proteins and lactic acids in milk."
References:
1. Koop, E. The Surgeon's General's Report. Wash.Pub. No. 88-50210. 1988.
2. Werbach, R. Nutritional Influences on Illness.Tarz,Ca.1988.
3. Report of the Task Force on the Assessment of the Scientific Evidence Relating to Infant-Feeding Practices and Infant Health. Pediatrics, 74:579; 1984.
4. McDougall, J.M.D. Diet for A New America, 1992
5. .Welch,J. "Anti-Infective Properties of Breast Milk," J. Of Pediatrics, 94:1, 1979.
6. "Allergy and Cot Death: With Special Focus on Allergic Sensitivity to Cow's Milk Anaphylaxis," Clin & Exp. Allergy, 20:359, 1990.
7. Goldman,A. "Host Resistance Factors in Human Milk," J. Of Ped.82:1082; 1973.
8. Liebman, B. "Baby Formulas: Missing Key Fats?" Nutr. Action, October, 1990.
9. Ironside,A. "A Survey of Infantile Gastroenteritis," British Med J, 3:20, 1907.
10. Robbins,J. May they All Be Fed. Chapter 6, 1992.
11. Erasmus Udo, Fats that Heal, Fats that Kill, 2nd Ed. 1993.
12. Kaplan, S,M.D. Diet for A New America, Chapter 4, 1991.
13. McDougall, J. Ibid.
14. Erasmus,U. Ibid.
15. Barnard,N. M.D., Physicians Committee for Responsible Medicine, Conference, 1995.
16. Ursin, G. et. al. Milk Consumption & Cancer Incidence: A Norwegion Prospective Study. British J. of Cancer G1 no. 3, Mar. 1990, pp 456-459
17. Goldberg, Burton, The Group, Alternative Medicine: The Definitive Guide, Future Medicine Pub. 1996
18. Duggan, R. Dietary Intake of Pesticide chemicals in the United States, Pesticides Monitoring Journal, 2:140;1969
19. Bahna, S. Common Manifestations of Cow's Milk Allergy in Children, Lancet, 1:304; 1978
20. Bahna, S. Cow's Milk Allergy: Pathogenesis, Manifestations, Diagnosis, and Management, Advances In Pediatrics, 25:1; 1978
21. Eastham, E. Adverse Effects of Milk Formula Ingestion on the Gastrointestinal Tract-An Update, Gastroenterology, 76:365; 1979
22. Gerrard, J. Milk Allergy: Clinical Picture and Familial Incidence. Journal of the Canadian Medical Association, 97:780; 1967
23. Boat, T. Hyperactivity to cow's Milk in Young Children: Journal of Pediatrics, 87:23; 1975
24. Jakobsson, I. Cow's Milk Allergy as a Cause Of Infantile Colic, Australian Pediatric Journal, 13:276; 1977
25. Should Humans Drink Milk? Physicians Committee for Responsible Medicine, Guide to Healthy Eating, Nov.-Dec., 1990, pp 10
26. Moll, L. FDA Milk Testing Is Not Enough, Vegetarian Times, April, 1991, pp16
27. Human Food Safety and the Regulation of Animal Drugs Report, 99th Congress, 1st Session (HR):99-461, 1985; testimony of Michael Jacobson
28. Feskanich, D., et al. Milk, dietary calcium, and bone fractures in women: a 12 year prospective study, Am J. Publ Health, 1997; 87:992-7
http://www.afpafitness.com/articles/MILK.HTM