"Soy" much info. on soy!

Soy

1. History

Soy was introduced to United States in the early 1800s, but it originated in China as early as 2838 BC. The Chinese regarded soybean as one of the most important crop for their nation. Soybean had been a stable diet for the Chinese population for many years. It can be found in tofu, milk, sauce, oil, curd, livestock feeds etc.  As a food source, soy has been used in Asian cultures for thousands of years, with Asian populations consuming 60 to 90 g/day of soy The United States gained access to soybean through Samuel Bowen, a former East Indian Company sailor who visited China. During the Great Depression, Soy played a major role in regeneration of soil through nitrogen fixation technique. As Soybean become more and more popular in the US, we now produce 49% of the world’s soybeans. Soy foods have become increasingly popular among health-conscious individuals since the early 1990s. In 2000, approximately 27% of US consumers reported using soy products at least once a week. Soybean products are numerous and Because of its low cost, good nutritional value, and versatility, soy protein is used as part of food programs in less developed countries.

2. Medicinal and non-medicinal use

Soy is an important source of protein fiber and mineral. It has been used for menopausal symptoms, diabetes, osteoporosis and heart disease. It is also been showed to have anti-cancer effects although the mechanism on its activity is not completely clear. For non-medicinal use, it is used mainly as a food source, livestock feed, regenerating soil, infant formula, meat and dairy substitute etc.

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3. Major component(s) hypothesized to be the active ingredient(s). Include chemical

entities if applicable

Soybeans are high in nutritional value and contain up to 35% oil, 24% carbohydrate, and 50% protein. Fatty acids in beans include linoleic (55%), palmitic (9%), and stearic (6%) acids. Soybeans are rich in minerals and trace elements, including calcium, iron potassium, amino acids, and vitamins, and are a good fiber source. Soybeans contain isoflavone compounds known as phytoestrogens.

4. Theorized mechanism of action

Cancer

Isoflavones are selective estrogen receptor modulators, but also possess nonhormonal properties. The weak estrogenic action of soy isoflavones and other phytoestrogens suggest that they could lessen the harmful effects of more potent endogenous estrogens on breast and endometrial cancer.

Soy isoflavones have estrogenic, antiandrogenic, and other activities that could prevent prostate cancer or slow its progression.

Genistein reduced the synthesis of prostate-specific antigen, a marker of prostate cancer development and progression. Genistein inhibits the growth of androgen-dependent and androgen-independent prostate cancer cells.

Genistein acts as an oxidant (stimulating nitrate synthesis) and blocks formation of new blood vessels (antiangiogenic effect). Some studies show that genistein acts as inhibitor of substances that regulate cell division and cell survival (growth factors).

Cardiovascular disease:

Soy isoflavones exhibit strong biological properties in animals, causing arterial vasodilation, the lowering of serum cholesterol, and the inhibition of atherosclerosis. All these effects were seen in animal studies and the results have not translated well to human studies.

Diabetes:

Soy isoflavone diet showed that it could help improve insulin secretion. The exact mechanism on how it improves insulin secretion is not known.

Menopausal symptoms:

Because of their weak estrogenic activity, soy isoflavones have been hypothesized to improve several estrogen-dependent conditions, including perimenopausal vasomotor symptoms (eg, hot flashes) and postmenopausal bone loss. Interest in the use of soy and its derivatives for the treatment of menopausal symptoms has been encouraged by observations of a lower prevalence of menopausal complaints, especially hot flashes, among women in Asian countries where soy is an important component of the traditional diet.

Osteoporosis:

The effects of soy protein on osteoporosis are controversial. There are meta analyses that showed that soy protein can protect against decrease in bone mineral density and also in some case increase BMD. In other cases it had been showed to have no effect at all.

5. Clinical issues; DDIs, suggested dose, adv

erse effects, pharmacokinetics, overdose, use

in special population (pregnant women, elderly...etc.)

Dosing:

Soy isoflavones from 40 to 120 mg. (Dose that was used for clinical trials)

Contraindications:

Women who have current or history of estrogen-dependent tumors (including breast cancer) should consult their physician prior to higher than dietary consumption of soy due to its possible effect on aggravating tumor.

Pregnancy/Lactation:

Generally regard as safe.

Interactions:

None well documented.

Adverse Reactions:

Soybeans and their products are generally well tolerated. Minor GI disturbances have been reported.

 

6. Efficacy vs. safety

Increased breast cancer risk and it is possible that isoflavones in soy may actually stimulate breast tumor growth through their estrogenic activity.

Generally regarded as safe.

7. Information about the standard of the various preparations available

No soy-containing products researched were verified for safety, efficacy or purity.

8. Cost (compare to prescription medication)

A 30-day supply of simvastatin at Walgreens costs about $15 with insurance, and $30 without. A 180-tablet bottle (60-day supply) at Vitamin Shoppe costs $23.65. Comparatively, the soy product has a lower cost per day than the simvastatin, however, the therapeutic impact on lower cholesterol may be questionable for soy.

A 4-week supply of alendronate at WalMart pharmacy costs $9, whereas Amazon.com sells “Jarrow Formulas – IsoRich Soy GMO free” for $13.29. Jarrow’s claims that their supplement is beneficial for cardiovascular function, menopausal support and bone health. Instructions are to mix 29g (31-day supply) of powder with milk or juice daily. Comparatively, alendronate sells for a cheaper cost per month for aiding in bone health.

9. Prevalence of use:

Dr. Shimp stated that soy supplements were more popular about 8-10 years ago when it first emerged as a supplement, but nowadays it’s not very prevalent anymore. Concerns with breast cancer risk (albeit conflicted studies) may also have factored into the decline of soy supplementation.

10. Evidence-based studies

A randomized placebo-control double blind study was done with women aged 45 to 60 within 5 years of menopause and with bone mineral density T score of -2.0 or higher. Patients were randomized to receive placebo or 200 mg of soy isoflavone tablets. The study showed that after 2 years, no significant differences were found between treatment (n=122) and placebo (n=126) group for changes in bone mineral density in the spine (-2.0% and -2.3%, respectively). This study also found that a significantly larger portion of the soy group experienced hot flashes and constipation compared with the control group.

Levis S, Strickman-Stein N, Ganjei-Azar P, Xu P, Doerge DR, Krischer J. Soy Isoflavones in the Prevention of Menopausal Bone Loss and Menopausal Symptoms: A Randomized, Double-blind Trial. Arch Intern Med. 2011;171(15):1363-1369. doi:10.1001/archinternmed.2011.330.

In a separate 2013 study with 128 patients (67 active, 61 placebo), Mainini et al. showed that treatment with 19.2 mg of soy isoflavones daily resulted in a significant reduction (p <0.05) of the number of hot flashes compared to placebo in one month and at 3 months. Additionally, they found no significant difference in total cholesterol, LDL, HDL, or triglycerides.

Nonhormonal management of postmenopausal women: Effects of a red clover based isoflavones supplementation on climacteric syndrome and cardiovascular risk serum profile

Mainini G., Torella M., Di Donna M.C., Esposito E., Ercolano S., Correa R., Cucinella G., Stradella L., Luisi A., Basso A., Cerreto F.V., Cicatiello R., Matteo M., De Franciscis P.

Clinical and Experimental Obstetrics and Gynecology 2013 40:3 (337-341)

In a meta analysis of PubMed, Taku et al. found that soy isoflavones significantly reduced total cholesterol and LDL, but did not change HDL and triglycerides, and that the change in LDL were higher in hypercholesterolemic patients than in normocholesterolemic patients.

Am J Clin Nutr. 2007 Apr;85(4):1148-56.

Soy isoflavones lower serum total and LDL cholesterol in humans: a meta-analysis of 11 randomized controlled trials.

Taku K, Umegaki K, Sato Y, Taki Y, Endoh K, Watanabe S.

A study was conducted in 2008 that suggested consuming soy legumes led to a decreased incidence of developing type 2 diabetes.

Am J Clin Nutr. 2008 Jan;87(1):162-7.

Legume and soy food intake and the incidence of type 2 diabetes in the Shanghai Women's Health Study.

Villegas R, Gao YT, Yang G, Li HL, Elasy TA, Zheng W, Shu XO.

In a meta analysis, soy consumption at the “level of Asian populations” have no detrimental risks to breast cancer or breast cancer recurrence. One 2014 study found that soy foods and isoflavones has modest reductions in the risk of breast cancer. This 2014 study also showed that soy had no influence on protection of bone health.

Curr Opin Clin Nutr Metab Care. 2012 Nov;15(6):586-91. doi: 10.1097/MCO.0b013e328359156f.

Soy products in the management of breast cancer.

Magee PJ, Rowland I.

Altern Ther Health Med. 2014 Jan;20 Suppl 1:39-51.

Soy foods and supplementation: a review of commonly perceived health benefits and risks.

D'Adamo CR, Sahin A.

11. Comparable prescription or non-prescription medications: See above

12. Any regulatory issues

FDA issued a statement in April 2013 stating that labeling requirements of soy and lowering CHD must have the word “may” or “might” on the product. Additionally, the substance claim must be “soy protein” not just soy. The disease must state “coronary heart disease” or “heart disease.” The fat component must be “cholesterol” or “saturated fat.”

Health store Views

A Vitamin Shoppe representative seemed to have scripted lines when answering questions. When asked about side effects of soy, she was very general, stating that “side effects vary from person to person.” She suggested we speak to our doctor for more information on that. We didn’t ask her knowledge level on it explicitly, but it seemed she wasn’t very well versed on the topic.

A pharmacist at Village Apothecary Pharmacy on South University said that it's used to deal with hot flashes in menopause because it contains an estrogen/estrogen analog. He'll tell patients not to take soy and Rx hormones at the same time without talking to their doctor.