Tori Hudson, N.D. See book keywords and concepts |
In a study estimating the daily intakes of soy isoflavones in the diets of 478 postmenopausal Japanese women who reported soy consumption, high consumption of soy products was associated with increased bone mass.49
Soy is also a good source of calcium. A diet that includes greater amounts of soy products can account for a meaningful amount of calcium, and some soy foods can offer as much or more calcium than a serving of dairy products.
An adequate intake of calcium and vitamin D is fundamental for bone health and is an important adjunct to drug treatments for osteoporosis. |
Steven G. Pratt, M.D. and Kathy Matthews See book keywords and concepts |
It does provide soy isoflavones but, like soy sauce, its sodium content is high and thus doesn't make a good general source of soy protein.
SOY SUPPLEMENTS
People often ask me if they can just take a soy supplement. Once the health benefits of soy became well publicized, it wasn't long before soy isoflavones were available in health food stores. These supplements, containing concentrated soy isoflavones, are promoted as being beneficial particularly to women as relief from menopausal symptoms. You know my answer: if you want to get the health benefits of soy, you must rely on the whole food. |
Bottom Line Health See book keywords and concepts |
No one knows if soy isoflavones have any effect on breast cancer in humans. A recent two-year study of premenopausal women found that soy had no effect on breast tissue density, an indicator of cancer risk.
MORE ON SOY
Some people don't eat soy because they're just not familiar with it. The soybean is a member of the legume (pea) family. It forms clusters of three to five pods, each with two to four beans. Tofu, miso, tempeh and other foods made from soy contain isoflavones. Some soy products, such as soy sauce and soy oil, contain soy but are not good sources of isoflavones. |
Elaine Magee See book keywords and concepts |
A recent Italian study suggests soy isoflavones perhaps don't actually minimize hot flashes but instead have the ability to improve mood, thereby rendering women less inclined to care about their hot flashes. The theory makes sense, given that estrogen receptors exist in the mood area of our brain, and soy is rich in natural plant estrogens.
Soy good for the heart? The definitive news on how soy affects heart health has not yet been reported because researchers are still looking into whether-and how-it helps. |
Tori Hudson, N.D. See book keywords and concepts |
In some susceptible individuals, or in some who take very high doses of nutritional supplementation of soy isoflavones (above 200 mg per day) or have an extreme diet low in other nutrients and high in soy, it is prudent to be aware of potential but extremely rare problems with soy ingestion.
One of the greatest fears for women contemplating menopause treatment options is the concern about estrogen replacement therapy and breast cancer. |
Bill Sardi See book keywords and concepts |
Cancer Epidemiology Biomarkers Prevention 13: 644-48, 2004]
However, a comparable study in which 52 men were given 60 mg of soy isoflavones over a 12-week period of time,
Aen in Japan Japanese men in U.S.
3W fat, high soy High fat, low soy
Sniirrp- I Irnlnnv AA- 7A5-71 OCldA
N-< I I U |J I V I / found that only one experienced more than a 50% reduction in PSA level. [Urology 63: 259-63, 2004] This type of study may indicate PSA is a poor measure of the value of soy rather than the conclusion of researchers that soy appears to be ineffective. |
Journal National Cancer Institute 95: 906-13, 2003] It is obvious that the hot water in soup making produced a hot-water extract of the soy isoflavones which produced the health benefits.
1 cup miso soup (soybean paste)
3 cups miso soup (soybean paste)
109.7 per 100,000 risk for breast cancer
57.2 per 100,000 risk for breost concsr
GENISTEIN
Genistein is a principal plant estrogen molecule found in red clover and soy and deserves special attention.
Genistein inhibits breast cancer growth at low concentrations and promotes growth of breast cancer at high concentrations. |
Also, soy isoflavones should not be taken by postmenopausal women for the specific purpose of decreasing their risk of breast or endometrial cancer." This is very puzzling, given the fact that the American Heart Association says the inclusion of soy protein foods as part of an otherwise healthy diet is well justified. Good for the heart but unclear for breast health. [Endocrinology 1:293-311, 2002]
Another report says: "Of current concern is the effect of phytoestrogen compounds on the growth of pre-existing breast tumors. |
Joe Graedon, M.S. and Teresa Graedon, Ph.D. See book keywords and concepts |
But iodine deficiency makes animals (and presumably humans) susceptible to clinical problems caused by soy isoflavones interfering with thyroid peroxidase.667 A person who is already hypothyroid should probably be cautious about basing a diet on soy burgers, soy milk, soy hot dogs, soy shakes, and the like. And we are skeptical about the value of soy isoflavones in pill form for someone with an underactive thyroid. Dr. Arem suggests that those who are hypothyroid limit soy-based meals to no more than three per week.668
• • •
Q. / was diagnosed with hypothyroidism in 1992 and started on 0. |
Bill Sardi See book keywords and concepts |
A study of 15,555 Dutch women aged 49-70 years found a high intake of soy isoflavones or mammalian flaxseed and other lignans is not significantly related to breast cancer risk. [American J Clinical Nutrition 79:282-8, 2004]
—? The strongest data show that phytoestrogens reduce the number and intensity of hot flashes, although the reduction is a modest 10-20%. [Journal Nutrition 133:1983S-6S, 2003]
—? A review of published dietary intake studies involving prostate cancer did not show any protective action from phytoestrogens. |
Joe Graedon, M.S. and Teresa Graedon, Ph.D. See book keywords and concepts |
I bought soy isoflavones containing "natural hormones." I began taking these capsules three times a day during the last week of my next packet of pills. For the first time in many years, I had no headache! I dreaded the next month, fearing the success of the soy isoflavones had been a fluke, but it has worked for 3 months in a row.
Doctors have also experimented with longer-acting triptans, particularly Amerge, Frova, and Naramig. |
Elaine Magee See book keywords and concepts |
In lab studies, calcium in combination with soy isoflavones was found to preserve bone mineral density to a greater extent than either did alone. So it seems that in this case, two nutrients were actually better than one. However, if you want to reap similar rewards, note that not all soy products are calcium fortified. The only way to know for sure is to check the nutrition information label. Look toward the bottom of the label, where it lists the percentage Daily Value of various vitamins and minerals. |
Bill Sardi See book keywords and concepts |
European researchers recently provided a dietary supplement containing soy isoflavones, lycopene, milk thistle and other antioxidants to males who had undergone surgery or radiation therapy and found it slowed the progression of the disease. [European Urology 48: 922-30, 2005]
Conclusions and action plan
The major risk factors for prostate cancer have been described in various publications, geographical (northern climates), obesity, skin color (black), calcium (high intake), all which involve the lack of vitamin D. |
Ann M. Coulston and Carol J. Boushey See book keywords and concepts |
In humans, the conversion of soy isoflavones (genistein and daidzein) to the more potent metabolite (equol) appears to be dependent on intestinal microflora. Evidence for this conversion comes from animal and clinical studies. First, all rodents are equol producers, except those that are bred germ-free. Second, infants fed soy-based formulas do not form a substantial amount of equol for the first 4 months of life, coinciding with intestinal microflora development. |
Soy isoflavones improve systemic arterial compliance but not plasma lipids in menopausal and perimenopausal women. Arterioscler. Thromb. Vase. Biol. 17, 3392-3398. Russell, M., Cooper, M. L., Frone, M. R., and Welte, J. W. (1991). Alcohol drinking patterns and blood pressure. Am. J. Public Health 81, 452-157.
189. Stranges, S., Wu, T., Dorn, J. M., et al. (2004). Relationship of alcohol drinking pattern to risk of hypertension: a population-based study. Hypertension 44, 813-819.
190. Trevisan, M., Krogh, V., Farinaro, E., Panico, S., and Mancini, M. (1987). |
Thus, a role in breast cancer prevention for soy and soy isoflavones, as well as other phytoestrogens, has been investigated in numerous laboratory and epidemiological studies. However, phytoestrogens can act as estrogen agonists as well as antagonists, so it is possible that phytoestrogens could potentially promote mammary neoplasia. This would be most relevant for postmenopausal women, who do not have high levels of endogenous estrogens in the circulation that would compete for estrogen receptor binding sites. |
Figure 9 presents the changes in LDL-C in response to soy protein and soy isoflavones as a function of baseline LDL-C. It can be seen in Figure 9 that those with high baseline LDL-C have a greater LDL-C lowering response, and there is a dose-response relationship between soy protein intake and LDL-C lowering.
A subsequent meta-analysis was published [182], including 11 trials on soy protein containing isoflavones, in addition to the effects of soy protein containing enriched and depleted isoflavones. |
Joe Graedon, M.S. and Teresa Graedon, Ph.D. See book keywords and concepts |
There are also a few small studies showing that soy isoflavones taken daily can help prevent menstrual migraines. '
For the last few years I have been plagued with migraine headaches during the last week of my cycle, when my birth control pills contain no hormones.
I discussed this problem with my doctor, and she prescribed Mircette. This brand of birth control pill is supposed to have hormones during the last week. Unfortunately, I still suffered terrible headaches during that week. I was at my wits' end because I could hardly function.
I bought soy isoflavones containing "natural hormones. |
Gabriel Cousens See book keywords and concepts |
In men, eating soy isoflavones can significantly reduce testicular function and lower luteinizing hormone (LH) production, which is what signals the testicles to work. A high soy intake and potentially lower level of LH increases the probability of estrogen dominance in men, contributing to hair loss, swollen and cancerous prostates,34,35 and insulin resistance. Dorris Rapp, MD, a leading pediatric allergist, asserts that environmental and food estrogens are responsible for the worldwide reduction in male fertility. |
Ann M. Coulston and Carol J. Boushey See book keywords and concepts |
A very modest 3% reduction in LDL-C was found due to soy proteins; soy isoflavones generally had no effect on LDL-C [180], despite large
Results
Author
Year
Subjects
Design
TC
LDC-C
TG
HDL-C
Beauchesne-
2003
Hypercholesterolemic men
RCT: 26 days (n=17
Lean beef
I 18%
| 7%
| 19%
Rondeau, E.
(TC: >5.2mmol/l; each; 50 years) of lean et al. [287]
LDL-C: >3.4mmol/l) meat (^180g) versus
lean poultry (~180g)
Lean
1 8%
I 9%
I 25% versus fish (~270g). poultry
6-week washout period
Fish
| 5%
I 5%
I 20% in between each diet. |
Soy isoflavones lower serum total and LDL cholesterol in humans: A meta-analysis of 11 randomized controlled trials. Am. J. Clin. Nutr. 85, 1148-1156.
Azadbakht, L., Kimiagar, M., Mehrabi, Y., Esmaillzadeh, A., Hu, F. B., and Willett, W. C. (2007). Soy consumption, markers of inflammation, and endothelial function: A crossover study in postmenopausal women with the metabolic syndrome. Diabetes Care 30, 967-973. Matthan, N. R., Jalbert, S. M., Ausman, L. M., Kuvin, J. T., Karas, R. H., and Lichtenstein, A. H. (2007). |
The Editors of FC&A See book keywords and concepts |
Yet there are studies of older women which show soy isoflavones lowering bone loss and increasing bone strength.
The International Food Information Council Foundation, an independent food safety, nutrition, and health organization says it's not possible at this time to draw a clear conclusion regarding the effects and safety of soy on long-term bone health. Until more information is available, play it safe — limit soy.
Healthy habits
Protect your bones with these lifestyle strategies. |
by Michael Murray, N.D. and Joseph Pizzorno, N.D. See book keywords and concepts |
Researchers have concluded that the anticancer activity of soy isoflavones may not be limited to estrogen-dependent tumors, as they have also been shown to cause death to cancer cells and inhibit angiogenesis, the formation of new blood vessels needed to fuel cancer cells.
The amount of soy found to be protective against the development of breast and prostate cancers delivers 25 to 100 milligrams per day of isoflavones. Many soy foods now state the level of isoflavones per serving. As you can see from Table 13.3, you do not need to eat huge amounts of soy foods to meet the recommended levels. |
Steven G. Pratt, M.D. and Kathy Matthews See book keywords and concepts |
These supplements, containing concentrated soy isoflavones, are promoted as being beneficial particularly to women as relief from menopausal symptoms. You know my answer: if you want to get the health benefits of soy, you must rely on the whole food. For one thing, no one is certain what's in various supplements: they may contain more or less isoflavones than they claim. Moreover, it's not clear if soy isoflavones behave exactly the way they do when they arrive in our bodies via the whole food. My recommendation is to avoid them. |
by Michael Murray, N.D. and Joseph Pizzorno, N.D. See book keywords and concepts |
We encourage cancer patients to consume at least one serving of soy (or 50 to 90 milligrams of soy isoflavones) per day unless you have a history of estrogen-positive breast cancer, in which case we encourage you to limit soy consumption to no more than three or four servings per week. Remember that you can use soy milk as the basis of whey protein smoothies.
Other Recommendations
For people with cancer, especially those undergoing chemotherapy, it's absolutely essential to maintain good hydration. Without adequate water your body cannot detoxify the drugs and remove them from the system. |
Mike Adams See book keywords and concepts |
It makes a sweet, low-sugar, healthy drink that provides the healing benefits of soy isoflavones along with a good balance of protein and fat.
I drink soy milk not only because of what's in it, but also because of what isn't in it. Soy milk doesn't contain pus, for example, which is always present in small quantities in dairy milk. Soy milk also does not contain blood, which is another substance that is allowed in small quantities in cows' milk. |
Jonny Bowden, Ph.D., C.N.S. See book keywords and concepts |
Period.
Since you don't have to look very hard to find "pro-soy" info but you might have to dig a little to get to hear "the other side," I suggest that anyone really interested in the soy controversy start by Googling Dr. Mary Enig and reading her extensive writing on soy, including "The Ploy of Soy" and "Soy Alert: Tragedy and Hype." For a more easy and entertaining—but no less scientifically documented read—get the essential book, The Whole
Soy Story: The Dark Side of Americas Health Food, by Kayla Daniel, Ph.D. (Daniel was a doctoral student under Enig. |
Joe Graedon, M.S. and Teresa Graedon, Ph.D. See book keywords and concepts |
And we are skeptical about the value of soy isoflavones in pill form for someone with an underactive thyroid. Dr. Arem suggests that those who are hypothyroid limit soy-based meals to no more than three per week.668
• • •
Q. / was diagnosed with hypothyroidism in 1992 and started on 0.025 milligram of Synthroid a day. This was gradually increased to 0.075 milligram in 1999.
Last month my blood test showed that my TSH (thyroid-stimulating hormone) was up to 5.0. (The normal range is 0.4 to 4.2.) The doctor increased my dose of Synthroid to 0.1 milligram. |
Vitamin E
The North American Menopause Society suggests taking vitamin E along with keeping cool, exercising, not smoking, eating soy isoflavones, and taking black cohosh as inexpensive, probably helpful nonprescription measures to alleviate hot flashes. Quite a few women have heard that vitamin E can be helpful for this symptom, and some have passed the advice along to their friends.
• • •
Q. I'm 53 and haven't had a period for a year. I have no problems other than hot sweats.
I recently started taking 400 IU of vitamin E each day and, much to my amazement, it really works. |
volker schulz and Rudolf Hansel See book keywords and concepts |
Additional research is required to determine the beneficial effects, if any, of pure soy isoflavones without accompanying protein on hypercholesterolemic persons (Liebman, 1998). All other potentially beneficial effects of soy isoflavones are less well documented. At this time, it is still impossible to state definitively whether the compounds can reduce the risk of breast or prostate cancer, osteoporosis, or hot flashes. However, this is a very fast-moving research field, and many present conclusions will almost certainly be subject to change as additional data become available. |