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Soy Good for Breast Cancer?

December 10th, 2009 No comments

Conventional wisdom dictates that since soy products contain products similar to estrogen, and that estrogen “feeds” certain types of cancer cells, then soy products in theory could make some breast cancers worse.  New research implies the opposite.

http://www.latimes.com/news/nationworld/nation/la-sci-soy9-2009dec09,0,6546847.story

Shari Roan writes,

Soy foods do not appear to increase the risk of breast cancer recurrence among survivors of the disease and may even confer some health benefits, new research suggests.

The study, published in today’s issue of the Journal of the American Medical Assn., should reassure breast cancer survivors that they need not scrupulously avoid soy foods, which have become increasingly popular in the United States in recent years. Research in animals has indicated that soy might increase the chances of breast cancer recurrence because it can act like the hormone estrogen, which promotes tumor growth.

So we CAN have our tofu and eat it, too!  What’s the “theory” behind how it makes cancer worse?  The isoflavones found in soy!

“Isoflavones can act as estrogens and add to the circulating pool of estrogen that is available and promote tumor growth. That is the concern,” said Bette J. Caan, a senior nutritional epidemiologist at Kaiser Permanente in Oakland, who was not involved in the current study.

Let’s see what the evidence says:

“Some doctors have advised women not to eat soy foods,” said Dr. Xiao Ou Shu, a professor of medicine at Vanderbilt University and lead author of the paper. “But another school of physicians think it’s safe. So it has been controversial. Our findings are important because, nowadays, it’s very difficult to avoid soy exposure. Soy flour and soy protein has been added to many foods in this country. Women may consume it and not even know it.”

Shu and her colleagues analyzed data from the Shanghai Breast Cancer Survival Study of 5,042 women in China. The breast cancer survivors were ages 20 to 75 and were followed for an average of four years.

The study showed that the higher a woman’s intake of soy foods, the lower her chances of cancer recurrence and death. Patients with the highest intake had a 29% lower risk of death during the study period and a 32% lower risk of breast cancer recurrence compared with patients with the lowest intake of soy foods. Soy food intake was measured by either soy protein or soy isoflavone intake. Isoflavones are hormones found in plants.

Ah ha! But this is just one study.  What about others? Maybe this is just a fluke?

In research released earlier this year, Caan and colleagues at UC Berkeley also found that higher soy intake was linked to lower rates of breast cancer recurrence. That study, published in the journal Breast Cancer Research and Treatment, followed almost 2,000 U.S. breast cancer survivors.

Okay. Not a fluke.  Does this mean people should go out and stuff themselves with tofu?

“We do not see a harmful effect of soy. That is the main message out of both studies,” Caan said. “Breast cancer survivors shouldn’t go out and take soy supplements, but they shouldn’t be afraid to drink soy milk in their coffee or eat tofu.”

tofu 2 Soy Good for Breast Cancer?

Can Tofu help prevent breast cancer recurrence?

What about differences between the breast cancer that responds to estrogen and those that don’t? The ones that take tamoxifen and not?

Shu’s study found no adverse effects from soy food intake among women whose tumors grow faster because of exposure to estrogen, called estrogen receptor-positive breast cancer, or among those whose cancers are unaffected by estrogen, called estrogen receptor-negative.

Nor were there differences in the findings among women who used the breast-cancer drug tamoxifen and those who did not. However, the study found that the drug was related to improved survival only among women who had low or moderate soy food intake, not higher intakes.

Ah, so don’t take too much.  Typical Chinese philosophy.  Also typical is the philosophy stated below:

“We cannot conclude from this study that there are no negative effects” from soy, she said. “We are studying soy as a whole food. We are not studying its components. It could be some components are not good for some people. But overall, we see women who eat a high amount of soy with better outcomes.”

There we go.  They’re looking at this like TCM doctors do: look at the WHOLE food, not just the individual components.

So what does TCM have to say about soy and it’s estrogen wanna bes?  Check this out from http://www.tcmpage.com/hpmenopause.html

Some of the most interesting research for those concerned with women’s health issues has been done in the field of plant chemistry, and specifically in studies of chemicals called phytoestrogens. Phytoestrogens are chemicals produced by certain plants which resemble the estrogens that are produced by the human body, and which bind readily to estrogen receptors in the human body, but which are “weaker” forms of estrogen than human estrogen. Scientific studies suggest that higher levels of “strong” estrogen correlate with higher incidence of breast cancer in women. That is why women with a history of breast cancer, or a high risk of developing it are not recommended to be on hormone replacement therapy. Unfortunately, women in Western countries are exposed to higher levels of environmental estrogen than women in undeveloped countries. It is estimated that our environment adds 40% more “strong” (and harmful) estrogens to the body than are produced naturally. This could explain why the incidence of breast cancer is higher in developed countries, and is probably a complicating factor in many hormone-related conditions. The benefit of eating foods which are high in phytoestrogens, like soy beans, is that the “weak” estrogen of the plant binds to the body’s estrogen receptors, displacing the “strong” estrogens, which are then discharged harmlessly from the body.

So the docs were right all along: eat your veggies!  I must warn though, that since soy milk is very cooling and yin, it might be damaging to the yang natures of children or those with too much cold in the body.  This could lead to bloatedness and other digestive problems.

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Astragalus Root for Swine Flu?

October 20th, 2009 2 comments

It has been reported in the media that Dr. Andrew Weil, MD has been critiqued by the US Food and Drug Administration for promoting astragalus root (huang qi) in general and his “Immune Booster” formula against Swine Flu.  My opinions on Whine, er Swine Flu aside, I would like to take this opportunity to discuss Huang Qi in general and it’s use against flus in particular.

But first I have to correct the online article as it showed the astragalus stem and leaves on the page.

 Astragalus Root for Swine Flu?

Leaves of the astragalus plant

Actually the Huang Qi often used is the astragalus ROOT

10024614 300x166 Astragalus Root for Swine Flu?

Astragalus root sliced and ready for use

Some excerpts from the article:

In a stern warning letter, the Food and Drug Administration and Federal Trade Commission told Weil Lifestyle LLC to stop marketing a dietary supplement called “Immune Support Formula” as a product that could “diagnose, mitigate, prevent, treat or cure the H1N1 Flu Virus in people.”

…The regulators go on to call out several other statements on the Web site about studies and scientific evidence to back the antiviral and immune-boosting power of the herb astragalus, an ingredient in Immune Support Formula.

…The NIH’s National Center for Complementary and Alternative Medicine says, “The evidence for using astragalus for any health condition is limited.” Data from small and preliminary studies suggest the herb may help the immune system fight infections, the NCCAM says, and researchers funded by the center are studying astragalus’s effects on the immune system.

…On “Larry King Live” last month, Weil recommended some “interesting strategies” to combat swine flu, including taking capsules of astragalus, which he called “perfectly safe.”

Offhand, I must say that while I admire Dr. Weil for having the courage to stand up for traditional medicine, I believe it is irresponsible to call astragalus, or any other medicinal plant “perfectly safe” and on Larry King Live yet!

I know that what he probably meant was that the amount of astragalus in his formulations were within accepted safety levels, but I believe that ordinary laymen who hear such statements as “perfectly safe” would interpret that to mean “I can take it like candy.”  Not the case.  Sure, it has a high theapeutic index, with a dosage range from 9-30 grams (relatively high) but still there is an UPPER LIMIT.

But what is Astragalus Root all about?  It’s common english name is milkvetch and it’s scientific name is Astragalus propinquus or Astragalus membranaceus according to some.  The component used in Chinese Medicine is the root and thus the herbal component is called Radix Astralagi.

It is considered one of the 50 fundamental herbs in Chinese medicine.  According to tcm-healthinfo.org it can be used:

Orally, Huang Qi/Astragalus is used for treating the common cold and upper respiratory infections; to strengthen and regulate the immune system; and to increase the production of blood cells particularly in individuals with chronic degenerative disease or in individuals with cancer undergoing chemotherapy or radiation therapy. It is also used orally for chronic nephritis and diabetes. Astragalus is also used orally as an antibacterial and antiviral; a tonic; liver protectant; anti-inflammatory; antioxidant; and as a diuretic, vasodilator, or hypotensive agent.
Topically, Huang Qi/Astragalus is used as a vasodilator and to speed healing.
In combination with Ligustrum lucidum (glossy privet), astragalus is used orally for treating breast, cervical, and lung cancers.

Let’s take a sampling of research articles about the effects of Astragalus

Shen et al.  “Differential Effects of Isoflavones, from Astragalus Membranaceus and Pueraria Thomsonii, on the Activation of PPAR-alpha, PPAR-gamma, and Adipocyte Differentiation In Vitro“  American Society for Nutrition J. Nutr. 136:899-905, April 2006

Our data suggest the potential value of isoflavones, especially biochanin A and their parent botanicals, as antidiabetic agents and for use in regulating lipid metabolism. – from abstract.

Here’s an article so good I have to quote the whole thing with some points highlighted…

Could an herbal therapy that’s been used for centuries in Chinese medicine to strengthen the immune system hold the key to an effective treatment for Acquired Immune Deficiency Syndrome, better known as AIDS? A new study by scientists at the UCLA AIDS Institute says that’s possible.

The research, set to be published in the Journal of Immunology November 15th (available on-line now at http://www.jimmunol.org/cgi/content…), concludes astragalus root contains a substance that could make it a powerful weapon in the fight against the HIV virus that causes AIDS. “This has the potential to be either added to or possibly even replace the HAART (highly active antiretroviral therapy), which is not tolerated well by some patients and is also costly,” co-author Rita Effros, a professor of pathology and laboratory medicine at the David Geffen School of Medicine at UCLA and member of the UCLA AIDS Institute, said in a press statement.

So what specifically appears to make astragalus effective in treating HIV infection? The key finding in the UCLA study shows a substance in the herbal therapy prevents or slows down the progressive shortening of a part of immune system cells called telomeres.

A telomere is a region found at the end of each cell chromosome. It does not contain genes but does contain repeated DNA sequences. As immune cells age, telomeres gets shorter and shorter when the cells divide. Eventually, the cells change, can no longer divide and their ability to fight infections is compromised. This phenomenon is dubbed replicative senescence.

For a strong immune system to function correction, a great deal of cell division has to take place. For example, when a virus invades the body, killer T-cells (known as CD8 T-lymphocytes) have receptors that recognize the invader and begin to create versions of themselves to fight the virus — through division, they create more and more of an immune system “army” to knock out the virus. In most healthy people, the telomeres in cells are long enough to allow cells to divide many times without a glitch. What’s more, T-cells can switch on an enzyme called telomerase to prevent the telomeres from shortening and to boost the ability of the cells to divide.

“The problem is that when we’re dealing with a virus that can’t be totally eliminated from the body, such as HIV, the T-cells fighting that virus can’t keep their telomerase turned on forever. They turn off, and telomeres get shorter and they enter this stage of replicative senescence,” Dr. Effros explained in a statement to the press.

Previous studies have shown that injecting the telomerase gene into T-cells can keep the telomeres from shortening so they fight HIV longer than they normally would be able to. However, this complicated and expensive gene therapy isn’t a practical way to treat the millions of people infected with the HIV virus. Good news: the current study shows that treatment with a natural substance called TAT2 found in astragalus could be a far better approach.

The reason? Not only did the researchers find that the astragalus-derived TAT2 slowed the shortening of telomeres, but it also boosted the CD8 T-lymphocytes production of soluble factors called chemokines and cytokines. And these substances have been shown in other research to shown to block the replication of the HIV virus.

“The ability to enhance telomerase activity and antiviral functions of CD8 T-lymphocytes suggests that this strategy (using TAT2 from astragalus) could be useful in treating HIV disease, as well as immunodeficiency and increased susceptibility to other viral infections associated with chronic diseases or aging,” the researchers wrote in their research paper.

According to the Memorial Sloan-Kettering Cancer Center web site (http://www.mskcc.org/mskcc/html/691…), astragalus has no reported adverse effects. It has been used in traditional Chinese medicine to support and enhance the immune system and for heart disease. Currently, the herb is widely used in China for chronic hepatitis, colds and upper respiratory infections and as an adjunctive therapy in cancer. The remarkable herbal therapy has also shown promise in animal experiments as a way to prevent dementia.

WOW.  “Possibly replace HAART”.  THIS is the Huang Qi that is they doubt has an effect against a FLU?

Some other research cited by this article from the University of Maryland Medical Center website

Chen KT, Su CH, Hsin LH, et al. Reducing fatigue of athletes following oral administration of huangqi jianzhong tang. Acta Pharmacol Sin. 2002;23(8):757-761.

Duan P, Wang ZM. [Clinical study on effect of Astragalus in efficacy enhancing and toxicity reducing of chemotherapy in patients of malignant tumor]. Zhongguo Zhong Xi Yi Jie He Za Zhi.2002;22(7):515-517.

Hao Y, Qiu QY, Wu J. [Effect of Astragalus polysaccharides in promoting neutrophil-vascular endothelial cell adhesion and expression of related adhesive molecules]. Zhongguo Zhong Xi Yi Jie He Za Zhi. 2004;24(5):427-430.

Hei ZQ, Zhang JJ, Lin SQ, et al. [Effects of Astragalus membranaceus injection on nitric oxide and endothelin concentration of intestinal mucosa after hemorrhage shock-reperfusion in rats]. Zhongguo Zhong Yao Za Zhi. 2004;29(5):444-447.

Kim SH, Lee SE, Oh H, et al. The radioprotective effects of bu-zhong-yi-qi-tang: a prescription of traditional Chinesemedicine astragalus. J Chin Med. 2002;30(1):127-137.

Mao SP, Cheng KL, Zhou YF. [Modulatory effect of Astragalus membranaceus on Th1/Th2 cytokine in patients with herpes simplex keratitis]. Zhongguo Zhong Xi Yi Jie He Za Zhi. 2004;24(2):121-123.

Shao BM, Xu W, Dai H, et al. A study on the immune receptors for polysaccharides from the roots of Astragalus membranaceus, a Chinese medicinal herb. Biochem Biophys Res Commun. 2004;320(4):1103-1111.

Shi FS, Yang ZG, Di GP. [Effect of Astragalus saponin on vascular endothelial cell and its function in burn patients]. Zhongguo Zhong Xi Yi Jie He Za Zhi. 2001;21(10):750-751.

So the evidence IS there.  But why the need to bash it?  Like I said, if properly used, the commonly found and inexpensive Astragalus root (btw, it’s also used in contemporary asian cooking) can REPLACE expensive drugs that are money-makers for Big Pharma… maybe.

Sources:

Hensley, Scott.  “FDA and FTC Slam Swine Flu Claims For Dr. Weil Supplement” http://www.npr.org 16 October 2009.  20 October 2009 <http://www.npr.org/blogs/health/2009/10/fda_and_ftc_slam_swine_flu_cla.html>

tcm.health-info.org “Huang Qi – Astragalus Root”. 20 October 2009 <http://tcm.health-info.org/Herbology.Materia.Medica/huangqi-properties.htm>

Shen et al.  “Differential Effects of Isoflavones, from Astragalus Membranaceus and Pueraria Thomsonii, on the Activation of PPAR-alpha, PPAR-gamma, and Adipocyte Differentiation In Vitro“  American Society for Nutrition J. Nutr. 136:899-905, April 2006

University of Maryland Medical Center. 20, October 2009 <http://www.umm.edu/altmed/articles/astragalus-000223.htm>

Baker, Sherry. NaturalNews.com 13 November 2008. 20 October 2009 <http://www.naturalnews.com/024799_HIV_astragalus_AIDS.html>

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