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RE: Evidence-based Medicine
One thing you must realize before writing health related articles, Brandon, is that the medical community has an accepted method of research that it uses to determine if 1, a study is valid, and 2, if the study can be used to prescribe treatment, or as in this case, lifestyle changes.
I found this to be quite an arrogant statement. This is nothing specific to medicine, it's called rational thought. AKA, is a claim justified, and does it apply to a situation?
After examining your sources I find that this aforementioned technique is highly lacking.
And after examining the time delay from the posting of Brandon's article and your net scouring, I think you may be the victim of your own critique. (Unless of course you've done sufficient soy study in the past. But I'm guessing since most of your sources were from the same data pool, a sufficient study wasn't done.)
I am unable to find any article that states that protein is “over-consumed.”
"The average man in the US eats 175% more protein than the
recommended daily allowance and the average woman eats 144%
more."
--Surgeon General's Report on Nutrition and Health, 1988
After finding that evidence in about two seconds, I didn't even bother reading any farther. Maybe it's old info, maybe it's not. I don't know and it's not the point. All I'm saying is that academic discussion is great, but not everyone has the time to write a doctoral thesis. I just think it would be more beneficial for everyone if we could do without the holier-than-thou-style lectures on how to write and simply state what we know (or think) to be true. If you're going to attack someone with guns a'blazin', you might want to heed your own advise and do some decent research first and avoid all the you're-so-dumb finger pointing.
...but other than that, thanks for the post. I'm sure once you sift through the attacks it's fairly informative.
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Evidence-based Medicine
One thing you must realize before writing health related articles, Brandon, is that the medical community has an accepted method of research that it uses to determine if 1, a study is valid, and 2, if the study can be used to prescribe treatment, or as in this case, lifestyle changes. The practice of evidence-based medicine is a key feature in the training process of doctors, as they must sort through study upon study to determine which one they believe enough to use to guide the treatment process of their patients (as many studies can contradict each other in their conclusions.)
After examining your sources I find that this aforementioned technique is highly lacking. I think this may have lead you to draw some hasty, and in some cases, erroneous conclusions about milk and soy in general. I’ll briefly outline a few of these missteps in your article.
In fact, epidemiological research has shown that the countries with the highest dairy consumption rates, including the US, Sweden and Finland, also have the highest incidence of osteoporosis. The key is not to simply intake calcium, but to maintain an adequate calcium balance. In doing so, many factors are as important, if not more so, than calcium intake, including sodium intake, lifestyle (including physical activity (especially during teenage years), smoking, drinking, etc), animal protein intake, a healthy diet, gender, race, age, vitamin D status, and food calcium absorption rates.5
I searched several sources for this “epidemiological research” and eventually gave up on research articles and went straight to the National Osteoporosis Foundation (www.nof.org). The NOF seems to agree that all of the things you listed are important in the prevention and treatment of osteoporosis, but they don’t mention once the implied link you stated between consumption of dairy products and osteoporosis. In fact, they state that American women don’t get enough calcium and then recommend increased intake of calcium-containing diary products such as “low-fat milk, cheese, broccoli and other.”
To address your source: [PCRM] Physicians Committee for Responsible Medicine. 2001 Feb 28. A Letter Regarding Coca-Cola’s “Project Mother” Initiative to Develop Cow’s Milk Products Targeting Children. Retrieved from http://www.pcrm.org/news/Coke_milk_letter.html. Accessed 2004 Nov 14.
A letter from what appears to be a lobby organization to Coca-Cola probably isn’t the best reference for your article, especially when almost all of the claims you make regarding milk are lifted from this one source. A good physician will refuse to consider any medical claim not supported by at least a few valid references; he or she would prefer the quality of a well designed randomized, double-blind, placebo-controlled clinical trial. The writers of the letter fail to list any sources for their claims. So I did some homework for them (and you) and looked up some articles to support or refute their claims. See below.
Not only is protein over-consumed in the average Americans diet (which might explain why there is no listed DRI), but the animal protein contained in milk actually acts to block the absorption of calcium and can cause the human body to produce antibodies which are believed to damage the pancreas, leading to the development of type 1 diabetes (juvenile-onset).
I am unable to find any article that states that protein is “over-consumed.” I also find no research to support the claim that milk proteins inhibit the absorption of calcium. In fact, I did come across a study that showed that addition of milk proteins actually increased the absorption of calcium in animal models. 1
The claim that cow milk proteins can cause auto-immune destruction of pancreatic Beta-cells (in infants only) has some support in the literature, but medicine is far from making the broad statement that cow milk causes Type I Diabetes. Several studies have been published which seek to explore the effects of different dietary elements in the production of auto-antibodies in infants, as their immune systems are immature and prone to “mistakes”. One such study states that in animal models, cow milk proteins are modestly diabetogenic (prone to cause diabetes), but wheat and soybean proteins cause higher rates of autoimmune disease. 2
Cow’s milk consumption has been connected to numerous diseases and cancers. In children, cow's milk consumption has been linked to anemia, colic, allergies, asthma, and juvenile-onset diabetes. In adults, cow's milk consumption is related to heart disease, prostate cancer, and breast cancer. The milk sugar lactose and its breakdown product galactose have been linked to increased risk of ovarian cancer. According to a review published by the World Cancer Research Fund and the American Institute for Cancer Research, at least 11 human population studies have linked dairy product consumption and prostate cancer.
In the medical literature it is well understood that stating that some factor “has been linked” to something else does not imply a definite cause and effect relationship. This can cause some confusion without taking that understanding into consideration. For example, one could say that “being left-handed has been linked to stuttering” (which some studies support), that that isn’t the same thing as saying “being left-handed causes stuttering.” To state that one thing “is linked” to another simply says that there may or may not be a relationship between the two, and if one exists it is poorly understood.
To address some of the above “links” I looked up articles which addressed milk and childhood asthma, adult heart disease, and cancer.
Thorax is a very well respected journal among pulmonologists (lung specialists). According to this journal, milk consumption has been shown to actually decrease the incidence of asthma symptoms in pre-school children. 3
Heart disease in adults has a wide spectrum of etiologies. Risk factors include dyslipidemia (too much “bad” cholesterol and not enough “good” cholesterol), hypertension, obesity, diabetes (usually type II), and a family history of coronary artery disease. Apparently milk proteins exert an anti-hypertensive effect (similar to pharmaceuticals such as lisinopril) and can act to reduce the incidence of hypertension. 4
I did find a few articles about the animal estrogens in cow milk leading to a higher incidence of prostate cancer and ovarian cancer. It would be interesting to see a study comparing the incidence of these cancers among a group of milk drinkers and a group of soy milk drinkers, as many proponents of soy state that the content of phyto-estrogens (plant based estrogens) are helpful in post-menopausal women. Unfortunately no such head-to-head study has been done thus far. 5, 6, 7
Milk proteins have been shown to decrease the incidence of malignant tumors of the head and neck. So I guess at this point you have to weigh the value of your prostate against that of your head. (kidding.) 8
The approval of a synthetic growth hormone, rBST (recombinant bovine stomatotropin), by the US Food and Drug Administration is a concern as well. This hormone has no therapeutic value but to increase the production of milk. Already under stress from the existing high production demands, dairy cows may now suffer more frequent bouts of mastitis. Cows treated with rBST may result in the administering of more antibiotics, the residue of which may end up in the milk supply.
Ah, the Toronto Vegetarian Association, now that’s an unbiased source, again, with lots of references. Or not. Show me some evidence that rBST increases the incidence of mastitis and then I’ll do some research. Then show me some lab data from all the mastitis infected cows and their penicillin tainted milk. Until then, it would be best to leave speculation out of this discussion.
There is also some evidence to suggest that cow’s milk-based cheese might actually be addictive. Studies have detected morphine in milk from cows and humans, and also a protein named casein that releases numerous opiates in the brain, serving as a reward that leads you to eat it habitually.
Wow, now these “points” were rich with error. I read an article in Reader’s Digest a few years back which discussed the appetite suppressing properties of dairy foods and explored the link between milk-drinking and decreased incidence in obesity. I wouldn’t dare quote Reader’s Digest though in the discussion of medical or biological topics; it has no expertise as a publication. That same problem is found in quoting the Houston Chronicle.
But I will quote a study from the Department of Nutrition and Food Sciences, at Utah State University. Results from their study showed that milk-proteins had no effect on appetite or satiety. I was unable to find an article which contradicted this finding. 9 I was also unable to find any piece of literature whatsoever which supported the statement that casein had any place in the “reward pathway.” Opiates are drugs derived from opium; they aren’t “released” in the brain any more than penicillin is “released” by the kidney.
Of course morphine does act in the reward pathway. However, the half-life of morphine is 2-3 hours and is cleared mostly by the liver. The chances that a cow receiving morphine would inadvertently pass levels of the drug high enough to affect humans in milk are pretty slim.
In addition, the phytochemicals found in abundance in Soymilk have been found to reduce the risk of cancer, particularly isoflavones, genistein and daidzein. There is also evidence that isoflavones in particular assist in the prevention of osteoporosis by reducing calcium loss from bones. They also mimic estrogen and can reduce the effects of menopause symptoms.
Scientists are just beginning to explore the potential of isoflavones. Several studies have shown improvements in the areas you listed above. However, it would have given better credence to your statement had you not quoted the Houston Chronicle.
Soy has also been an effective means of diabetes management through its ability to control blood sugar levels.
In medical literature, saying that something is “effective” means that it is comparable to the current treatment regimen. I have been unable to find evidence to support the claim that soy is able to manage blood glucose anywhere close to what an Endocrinologist can do. Insulin, Metformin, and the glitazones are all prescription medications that have been approved after years of testing, research, and double-blind placebo-controlled trials. Where are such trials on soy?
If you are going to accurately evaluate which is better, milk or soy, you would have to design a head-to-head study comparing the two in a set of categories, such as calcium absorption, cholesterol altering properties, hypertensive effects, etc. Then, for the best results, you would need a large sample size and testing procedures which would eliminate as much bias on the part of the examiner and examinee as possible. Only then would you be able to say that one appears superior to the other, with evidence in hand. If two scientists are quoting valid studies which contradict each other, then that's ok. That's science. It just shows that more research is needed. But don't come to the table with an alchemy manual when you want to debate Einstein. So, technically speaking, with your analysis, soy milk is not “the clear alternative.”
Each profession has an accepted method used to discuss the intricacies of the work at hand. Medical literature is unique in that the content of very specific discussions can be misinterpreted to indicate something altogether different than what was intended. For this reason evidence-based medicine has specific rules used to analyze studies and interpret results that attempt to ensure proper application of laboratory results into daily medical practice. Next time Brandon, try to stick with valid evidence-based medicine. A good place to start in understanding this topic can be found on http://www.cochrane.org/index0.htm.
1. Tsuchita H, Suzuki T, Kuwata T. The effect of casein phosphopeptides on calcium absorption from calcium-fortified milk in growing rats.
Br J Nutr. 2001 Jan;85(1):5-10.
PMID: 11227028 [PubMed - indexed for MEDLINE]
2. Wasmuth HE, Kolb H. Cow's milk and immune-mediated diabetes.
Proc Nutr Soc. 2000 Nov;59(4):573-9. Review.
PMID: 11115792 [PubMed - indexed for MEDLINE]
3. Wijga AH, Smit HA, Kerkhof M, de Jongste JC, Gerritsen J, Neijens HJ, Boshuizen HC, Brunekreef B; PIAMA Association of consumption of products containing milk fat with reduced asthma risk in pre-school children: the PIAMA birth cohort study.
Thorax. 2003 Jul;58(7):567-72.
PMID: 12832666 [PubMed - indexed for MEDLINE]
4. FitzGerald RJ, Murray BA, Walsh DJ.
Hypotensive peptides from milk proteins.
J Nutr. 2004 Apr;134(4):980S-8S. Review.
PMID: 15051858 [PubMed - indexed for MEDLINE]
5. Li XM, Ganmaa D, Qin LQ, Liu XF, Sato A.
[The effects of estrogen-like products in milk on prostate and testes]
Zhonghua Nan Ke Xue. 2003 Jun;9(3):186-90. Chinese.
PMID: 12861831 [PubMed - indexed for MEDLINE]
6. Qin LQ, Wang PY, Kaneko T, Hoshi K, Sato A.
Estrogen: one of the risk factors in milk for prostate cancer.
Med Hypotheses. 2004;62(1):133-42.
PMID: 14729019 [PubMed - indexed for MEDLINE]
7. Fairfield KM, Hunter DJ, Colditz GA, Fuchs CS, Cramer DW, Speizer FE,
Willett WC, Hankinson SE. A prospective study of dietary lactose and ovarian cancer.
Int J Cancer. 2004 Jun 10;110(2):271-7. PMID: 15069693 [PubMed - indexed for MEDLINE]
8. : Wolf JS, Li D, Taylor RJ, O'Malley BW Jr.
Lactoferrin inhibits growth of malignant tumors of the head and neck.
ORL J Otorhinolaryngol Relat Spec. 2003 Sep-Oct;65(5):245-9.
PMID: 14730178 [PubMed - indexed for MEDLINE
9. Gustafson DR, McMahon DJ, Morrey J, Nan R. Department of Nutrition and Food Sciences, Utah State University, Logan, UT 84322-8700, USA. deb@cc.usu.edu
Appetite is not influenced by a unique milk peptide: caseinomacropeptide (CMP). Appetite. 36(2):157-63, 2001 Apr.
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