Archive for soy
Caution Urged on Soy-Based Menopause Remedies
Remember what I said about natural medicine being held to a higher standard than traditional medicine? Here we have a researcher saying that we are not fully informed on how soy works in the human body and so we need to be careful with its use. A little reality check for the author–a large chunk of the drugs listed in the PDR have “mechanism of action unknown” on them and yet we throw these about like candy. But soy, with literally centuries of use, needs to be approached with caution. I would have to add that using soy supplements that have the percieved active constituents concentrated is probably not the best way to approach the use of soy in a healthy lifestyle.
British Endocrine Societies’ annual meeting in Harrogate, Yorkshire Apr 08 – So little is known about how plant oestrogens act on the human body that sales of soy supplements as a “natural” alternative to hormone replacement therapy (HRT) must be questioned, a researcher reported on Tuesday at British Endocrine Societies’ annual meeting in Harrogate, Yorkshire. Soy has been widely promoted as a natural alternative to HRT. Soy contains genistein, a plant oestrogen that has similar but weaker effects as the oestrogen found in women. But Dr. Saffron Whitehead, reader in reproductive physiology at St. George’s Hospital Medical School, London, said new studies on human cells have shown that genistein and other phyto-oestrogens may also block the enzymes that make these hormones. This could explain why the incidence of breast cancer, which in many cases is dependent on oestrogen, is about two thirds lower amongst Japanese and Chinese women who consume diets rich in soy compared with women living in England, she told her colleagues. Dr. Whitehead’s team examined the effects of phyto-oestrogens on human ovarian cells obtained during procedures for in vitro fertilization. The results showed that several phyto-oestrogens, including genistein, inhibited the conversion of androgen to oestrogen. The researchers believe this could be significant in postmenopausal women because as ovaries cease to function in menopause, oestrogen converted from androgen becomes the only source of oestrogen. “This finding is potentially important to the phyto-oestrogen story,” Dr. Whitehead said in a statement. “We really don’t know how phyto-oestrogens act in the human body. They could be weak oestrogen mimics, oestrogen blockers or enzyme inhibitors. “If they do stop the natural production of oestrogens, we should consider whether soy supplements be sold as a natural alternative to HRT.”
Soy Milk Lowers Blood Pressure in Mild to Moderate Hypertension
Soy milk is such an easy thing to add into a healthy lifestyle. It’s nice to see a study on the food as opposed to extracts.
Nutrition.org — Abstracts: Rivas et al. 132 (7): 1900
Importance of Equol—A Clue to Effectiveness of Soy Isoflavones
We see a familiar concept here. Soy isolflavones need to be acted on by beneficial bacteria in the gut to produce equol–a nonsteroidal estrogen-like compound that is believed to be one of the most potent antioxidants in this class. This may explain some of the discrepancies in soy benefit studies and is further proof for a holistic approach to health that would include lifestyle changes to support healthy bacterial flora. We see this same concept with soluble fiber and colon cancer–the fiber needs to be acted on by beneficial bacteria to produce butyrate to protect the colonocytes.
Nutrition.org — Abstracts: Setchell et al. 132 (12): 3577
Eat Soy: Prevent Baldness and Prostate Cancer?
A naturally occurring substance, DHT, or dihydrotestosterone, is a byproduct of the male hormone testosterone that helps control the development and functioning of the prostate gland; in most men, DHT is relatively harmless. However, some studies have shown that high levels of DHT can damage hair follicles, leading to male pattern baldness, or lead to an enlarged prostate or, in extreme cases, cancer of the prostate gland.
Researchers in the U.S. and China recently discovered that the answer to stopping DHT may be as easy as eating soy. The scientists conducted a pair of experiments in which two sets of rats were injected with “equol,” a molecule abundant in soybeans and other soy-based products. While the equol did not prevent DHT from being made, it “handcuffed” the hormone by binding to and deactivating it.
“Directly binding and inactivating DHT without influencing testosterone gives equol the ability to reduce many of the harmful effects of androgens [male hormones] without affecting the beneficial ones,” said the study’s lead researcher. Another one of the study authors added that the findings “are of immense clinical importance.”
Additional information about the benefits of sound nutrition can be found athttp://www.chiroweb.com/find/archives/nutrition.
Reference: Lund TD, Munson DJ, Haldy ME, et al. Equol is a novel anti-androgen that inhibits prostate growth and hormone feedback. Biology of Reproduction 2004;70:1188-1195.
Soy-Derived Phytoestrogens on Serum Lipids and Lipoproteins
This study finds no benefits of soy phytoestrogens on serum lipids. Before we run out and drop soy from a healthy lifestyle, there are a few things to consider here. First, soy foods, not supplements, have consistently been shown to be a part of a healthy lifestyle. I am a firm believer in the wisdom of Mother Nature, and believe that she put multiple factors in every food that work synergistically to achieve health benefits. Also, by adding soy into one’s diet, it will invariably be replacing more harmful animal products.
JCEM — Abstracts: Dewell et al. 87 (1): 118
Benefits of soy isoflavone regimen on menopausal symptoms
While I’m sure none of you fell over in surprise at the finding of this article, the fact that this appears in Obstetrics and Gynecology is a shocker to me. I wouldn’t have expected anything in this journal on this topic for at least 2 more decades… All sarcasm aside, remember that soy is just one tool in the natural approach to menopause. Evaluation and balance of adrenal function is another key approach to managing peri and postmenopausal signs and symptoms.
ScienceDirect – Obstetrics & Gynecology: Benefits of soy isoflavone therapeutic regimen on menopausal symptoms – Guest -
Phytoestrogens Associated with Favorable Cardiovascular Risk Profile
Remember research a few weeks back that found that high dose phytoestrogen did not affect blood lipids? I had to comment that the study used high dose phytoestrogen extract, not the whole food.
This article addresses phytoestrogen intake as a part of the diet and found favorable outcomes. I firmly believe that soy and other phytoestrogen containing foods are an essential part of a healthy lifestyle.
nutrition.org — Abstracts: de Kleijn et al. 132 (2): 276
Adrenocortical Effects of Oral Estrogens and Soy Isoflavones
Just in case this email gets to an ob/gyn and they think I don’t know what I’m talking about… This article (which is a monkey study) finds that both oral contraceptive and conjugated equine estrogens (i.e. Premarin) mess with the adrenal glands in a negative way, producing too much cortisol and not enough DHEA. And, since this imbalance is well known to contribute to insulin resistance, do I need say any more?
JCEM — Abstracts: Wood et al. 89 (5): 2319 -
Soy Has Both Beneficial & Potentially Adverse Cardiovascular Effects
This is another research article pointing to the beneficial effects of soy. This one does point out some of the potentially adverse effects, noting that Lp (a) increased and a decline in endothelial function in males. First of all, when looking at these adverse effects, we can consider it two steps backward for three forward. Also, this study once again looked at portions of soy, not the whole food. And, in a complete and balanced diet with fruits and vegetables other factors may mediate these adverse effects.
JCEM — Abstracts: Teede et al. 86 (7): 3053
Soy isoflavones improve lipids in normal & mildly hypercholesterolemia
Soy is believed to act through several mechanisms (most centered on the liver) to lower cholesterol levels. The effect in this study was mild, but, as with any functional approach, with added exercise, lowering of refined carbs (high insulin will stimulate HMG-CoA reductase..the enzyme that makes cholesterol), nutrients designed to stimulate healthy liver and gall bladder function (to aid in the elimination of cholesterol through the feces) and avoidance of saturated fat and I’m the effect is no longer mild.
AJCN — Abstracts: Wangen et al. 73 (2): 225 http://www.ajcn.org/cgi/content/abstract/73/2/225