Soy Isoflavone Intake Research Articles

Soy Isoflavones Intake and Obesity in Chinese Adults: A Cross-Sectional Study in Shanghai, China.

This study was designed to examine the association of soy isoflavones (SI) intake with different body measurements indicative of obesity in Chinese adults of Shanghai, a population consuming foods rich in SI. This study used baseline data from the Shanghai Gaofeng cohort study. SI intake was measured by using a self-reported food frequency questionnaire (FFQ). A restricted cubic spline (RCS) was performed to examine the possible nonlinear relationship of SI intake with obesity. A logistic regression model was applied to estimate the odds ratios (OR) and 95% confidence interval (CI). Compared with the lowest tertile group of SI intake, the highest tertile group had a lower prevalence of obesity and central obesity. The OR for overall obesity was 0.91 (95% CI: 0.85, 0.98) in the highest versus the lowest SI tertile group; the associations differed by sex and menopausal status. A negative association was also observed between SI intake and central obesity, and a significant modifying effect of sex was found on the association. No significant interactions were observed between SI intake and physical activity (PA) levels. Our results suggest that Chinese adults with higher dietary intake of SI may be less likely to be obese, particularly for postmenopausal women.

Effect of the Intake of Isoflavones on Risk Factors of Breast Cancer-A Systematic Review of Randomized Controlled Intervention Studies.

Epidemiological studies suggest that high intake of soy isoflavones may protect against breast cancer, but causal relationships can only be established by experimental trials. Thus, we aimed to provide a systematic review of randomized controlled trials (RCTs) on the effect of an isoflavone intake on risk factors of breast cancer in healthy subjects. After a systematic literature search in PubMed, 18 different RCTs with pre- and/or postmenopausal women were included and investigated for details according to the PRISMA guideline. In these studies, isoflavones were provided by soy food or supplements in amounts between 36.5–235 mg/d for a period of 1–36 months. Breast density, estrogens including precursors, metabolites, estrogen response such as length of menstrual cycle, and markers of proliferation and inflammation were considered. However, in most studies, differences were not detectable between isoflavone and control/placebo treatment despite a good adherence to isoflavone treatment, irrespective of the kind of intervention, the dose of isoflavones used, and the duration of isoflavone treatment. However, the lack of significant changes in most studies does not prove the lack of effects as a sample size calculation was often missing. Taking into account the risk of bias and methodological limitations, there is little evidence that isoflavone treatment modulates risk factors of breast cancer in pre- and postmenopausal women. Future studies should calculate the sample size to detect possible effects and consider methodological details to improve the study quality.

The association between soy-based food and soy isoflavone intake and the risk of gastric cancer: a systematic review and meta-analysis.

Soy contains many bioactive phytochemicals, such as isoflavones, which have the effect of preventing many cancers. Some studies have shown the beneficial effect of soy-based food and isoflavone intake on gastric cancer (GC), while others claimed no effect. Therefore, whether the beneficial effect of soy-based food is related to its fermentation or whether its protective effect comes from isoflavones still remains inconclusive. Our aim was to investigate the relationship between total soybean, fermented soybean, non-fermented soybean and isoflavone intake, and the risk of GC. Ten cohort studies and 21 case-control studies involving 916 354 participants were included. The association between soy-based food and isoflavone intake and the risk of GC was calculated with the pooled relative risks (RRs) for the highest versus lowest intake categories. The results showed that isoflavone intake might be a protective factor to GC, but the result was not statistically significant (RR=0.92; 95% CI: 0.79-1.07). However, total soybean intake could significantly decrease the risk of GC by 36% (RR=0.64; 95% CI: 0.51-0.80), which might be credited to non-fermented soybean products (RR=0.79; 95% CI: 0.71-0.87). In contrast, high intake of fermented soybean products could increase the risk of GC (RR=1.19; 95% CI: 1.02-1.38). High intake of total soybean and non-fermented soybean products could reduce the risk of GC, and high intake of fermented soybean products could increase the risk, which indicated that the beneficial effect of soy-based food might be related to its non-fermentation. However, high intake of isoflavones may not be associated with the incidence of GC. © 2021 Society of Chemical Industry.

Effects of Soy Isoflavones on Biochemical Markers of Bone Metabolism in Postmenopausal Women: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

This systematic review and meta-analysis of randomized controlled trials was performed to more completely assess potential changes in bone turnover marker levels in postmenopausal women during the intake of soy isoflavones. PubMed (Medline) and EMBASE were searched for relevant studies, and their quality was evaluated according to Cochrane criteria. The levels of markers were evaluated in a total of 1114 women who ingested mean daily doses of 98.2 mg (30.9 to 300) of soy isoflavones for 3 to 24 months, in comparison to those of 1081 subjects who used a placebo. Ten, eighteen, eight, and fourteen comparison studies were finally selected for an estimation of the effects on osteocalcin (OC), bone alkaline phosphatase (BAP), pyridinoline (PYD), and deoxypyridinoline (DPD), respectively. A summary of the results of intervention was as follows: 4.16%, 95% CI: −7.72–16.04, p = 0.49 for OC; 5.50%, 95% CI: −3.81–14.82, p = 0.25 for BAP; −12.09%, 95% CI: −25.37–1.20, p = 0.07 for PYD; and −7.48%, 95% CI: −15.37–0.41, p = 0.06 for DPD. The meta-analysis of the included studies revealed some statistically insignificant observations that soy isoflavones intake is associated with a trend in increased levels of OC and BAP, as well as a trend in reduced levels of PYD and DPD. Soy isoflavones may have a beneficial effect on bone formation markers, but this requires extensive multi-center research.

Association between Soy Food and Dietary Soy Isoflavone Intake and the Risk of Cardiovascular Disease in Women: A Prospective Cohort Study in Korea.

The association between soy food and soy isoflavone intake and cardiovascular disease (CVD) risk is uncertain, especially in women. We aimed to investigate this association in Korean women. We analyzed data from the Korean Genome and Epidemiology Study, including 4713 Korean women aged 40–69 years with no CVD or cancer at baseline. Dietary information was obtained using a validated semi-quantitative food frequency questionnaire, and the incidence of CVD was assessed using biennial self-reported questionnaires on medical history. The mean follow-up time was 7.4 years, during which 82 premenopausal and 200 postmenopausal women reported CVD incidence. The highest tofu, total soy foods, and dietary soy isoflavone intake groups were significantly associated with a decreased CVD risk in premenopausal women (tofu: hazard ratio (HR) 0.39; 95% confidence interval (CI), 0.19–0.80; total soy food: HR 0.36; 95% CI, 0.18–0.70; dietary soy isoflavones: HR 0.44; 95% CI, 0.22–0.89), whereas no association was observed in postmenopausal women. Other soy foods showed no association with CVD incidence. Dietary soy isoflavones and total soy foods are associated with a decreased CVD risk in premenopausal women. Among soy foods, only tofu showed significant health benefits.

Prediction models for breast cancer prognosis among Asian women.

Robust and reliable prognosis prediction models have not been developed and validated for Asian patients with breast cancer, a rapidly growing yet understudied population in the United States. We used longitudinal data from the Shanghai Breast Cancer Survival Study, a population-based prospective cohort study (n = 5042), to develop prediction models for 5- and 10-year disease-free survival (DFS) and overall survival (OS). The initial models considered age at diagnosis, tumor grade, tumor size, number of positive nodes, TNM stage, chemotherapy, tamoxifen therapy, and estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status. We then evaluated whether the addition of modifiable lifestyle factors (physical activity, soy isoflavones intake, and postdiagnostic weight change) improved the models. All final models have been validated internally and externally in the National Cancer Database when applicable. Our final models included age at diagnosis, tumor grade, tumor size, number of positive nodes, TNM stage, chemotherapy, tamoxifen therapy, ER status, PR status, 6-month postdiagnostic weight change, interaction between ER status and tamoxifen therapy, and interaction between age and TNM stage. The internal validation yielded C-statistics of 0.76, 0.74, 0.78, and 0.75 for 5-year DFS, 10-year DFS, 5-year OS, and 10-year OS, respectively. The external validation yielded C-statistics of 5- and 10-year OS both at 0.78 for Chinese ethnicity, 0.79 for East Asian ethnicity, and 0.75 and 0.76 for all ethnic groups combined. We developed prediction models for breast cancer prognosis from a large prospective study. Our prognostic models performed very well in women from the United States-particularly in Asian American women-and demonstrated high prediction accuracy and generalizability.

The effect of soy isoflavones and soy isoflavones plus soy protein on serum concentration of tumor necrosis factor-α? A systematic review and meta-analysis of randomized controlled trials.

In this study, we summarized the effect of soy isoflavones and soy isoflavones plus soy protein on serum concentration of tumor necrosis factor-alpha (TNF-α) among adult participants. We systematically searched Scopus, ISI Web of Science, Cochrane Library, PubMed, and clinicaltrials.gov for articles published up to May 2020. Effect size was calculated by mean change from baseline of TNF-α concentrations and its standard deviation (SD) for intervention and comparison groups. If the heterogeneity test was statistically significant, DerSimonian and Laird random effects model was used to estimate the summary of the overall effects and its heterogeneity. Nineteen and fourteen randomized clinical trials were included in our systematic review and meta-analysis, respectively. The result of overall effect size indicated a non-significant effect in serum concentration of TNF-α following soy isoflavones intake (WMD=0.2pg/ml, 95% CI: -0.13, 0.53; p=.226) and the combination of soy isoflavones and soy protein intake (WMD=0.02 pg/ml, 95% CI: -0.02, 0.06; p=.286). Subgroup analyses revealed no significant change in circulatory levels of TNF-α following soy isoflavones plus soy protein intake. In conclusion, the present systematic review and meta-analysis found insufficient evidence that soy isoflavones or the combination of soy isoflavones and soy protein significantly reduce serum concentration of TNF-α.

Pre-diagnosis and early post-diagnosis dietary soy isoflavone intake and survival outcomes: A prospective cohort study of early stage breast cancer survivors

BackgroundThere is concern that the estrogen-like effects of soy isoflavones may stimulate mammary tumor growth and interfere with the efficacy of breast cancer treatment. This study aimed to examine prospectively the associations of dietary soy isoflavone intake with all-cause mortality and breast cancer (BC) specific mortality and recurrence among BC survivors. DesignThe study included 1460 Chinese women with early-stage incident BC. Pre-diagnosis and early post-diagnosis soy food intakes were assessed at study entry, and at 18-month follow-up using validated soy food frequency questionnaire. Associations of soy isoflavone intake with prognostic outcomes within 48 months were examined using multivariable adjusted Cox proportional hazards models. ResultsWe observed increasing pre-diagnosis and early post-diagnosis soy isoflavone intakes up to the third quartile (Q3) were associated with reductions for adverse prognostic outcomes. Relative to the lowest quartile (Q1), the hazard ratios (HRs) for all-cause mortality for pre-diagnosis and post-diagnosis Q3 intake were respectively 0.34 (95% CI, 0.16–0.74), and 0.44 (95% CI, 0.22–0.89). A similar risk reduction was observed for pre- and post-diagnosis intakes and BC-specific mortality when comparing Q3 versus Q1 with the respective HRs 0.36 (95% CI, 0.16–0.82), and 0.49 (95% CI, 0.23–1.01). Subgroup analyses showed more favourable prognostic outcomes in association with moderate soy intake among premenopausal women, those with triple negative cancer and recipients of tamoxifen treatment. ConclusionModerate soy isoflavone intake was associated with favourable prognostic outcomes in Chinese early stage BC survivors.

Health Promotion Effects of Soy Isoflavones.

Soybeans contain several physiologically active ingredients, such as soy phytosterol, soyasaponin, soy protein, and lecithin, and are therefore expected to express the functionalities of said ingredients. Among them, soy isoflavones have been studied in recent years for their various functions, including their obesity-preventing effect, blood glucose level reducing effect, osteoporosis and breast cancer risk reduction, and anti-oxidative effect, and several health promoting effects and disease preventing effects are expected. For example, it has been determined that soy isoflavones reduce body and fat weight in experiments in which mice were fed a diet containing soy isoflavones in studies on anti-obesity. Epidemiologic studies with humans have also shown that women who consume more soybeans have lower BMI than those who consume less. We previously found that soy isoflavones may have anti-obesity effects in myoblasts through the activation of transcriptional coactivator PGC-1β, which increases energy expenditure. In recent studies, a decrease in blood glucose level due to soy isoflavone was seen in an experiment in which diabetic model mice were fed a diet containing soy isoflavone. It has also been suggested that soy isoflavone intake may increase bone mineral density in postmenopausal women and reduce the risk of breast cancer. This review focuses on the actions of soy isoflavones known to date, including their anti-obesity and anti-diabetic effects, bone loss preventing effects, and cancer risk reduction effects, and introduces reports on the health promotion and disease prevention effects of soy isoflavones.

Equol-producing status affects exercise training-induced improvement in arterial compliance in postmenopausal women.

Central arterial compliance decreases drastically after menopause. Regular intake of soy isoflavone and aerobic exercise increase arterial compliance. The equol is a metabolite of isoflavone daidzein by gut microbiome. We determined whether the equol-producing status affects aerobic exercise-induced improvement in carotid arterial compliance. Forty-three postmenopausal women were assigned to two intervention groups: 1) exercise and isoflavone (Ex+Iso, n = 27 females) or 2) isoflavone interventions (Iso; n = 16 females). Participants of the Ex+Iso intervention group completed an 8-wk aerobic exercise training, and all participants were administered with oral isoflavone supplements during the interventions. The equol-producing status (equol producers or nonproducers) was determined from urine equol concentrations after a soy challenge. In the Ex+Iso intervention group, carotid arterial compliance increased in the equol producers (0.084 ± 0.030→0.117 ± 0.035 mm2/mmHg), but not in the nonproducers (0.089 ± 0.028→0.097 ± 0.026 mm2/mmHg) after the intervention (interaction effect; P < 0.05). The magnitude of increases in carotid arterial compliance was significantly greater in the equol producers than in the non-equol producers (P < 0.05). In the isoflavone intervention group, there were no changes in any parameters after the intervention irrespective of the equol status. These results suggest that equol-producing status is obligatory to aerobic exercise training-induced improvements in central arterial compliance in postmenopausal women.NEW & NOTEWORTHY Isoflavone intake and aerobic exercise increase central artery compliance. Equol, a metabolite of isoflavone daidzein by gut microbiome, has beneficial effects on vascular function. We demonstrated for the first time that the interaction of aerobic exercise and equol production status plays an essential role in improvements in central artery compliance in postmenopausal women. More specifically, the equol-producing status was obligatory to exercise training-induced improvements in central arterial compliance in postmenopausal women.

Recent advances on the synthesis of flavans, isoflavans, and neoflavans

AbstractHeterocyclic compounds are the omnipresent structural cores comprising many natural and pharmaceutical products of biological significance. Significantly, heterocyclic compounds are widely distributed in nature, and also have applications in agrochemicals, sanitizers, as dyestuff, as copolymers, etc. Among heterocyles, flavonoids are a class of compounds that are highly interesting and constitute many natural products. In general, all flavanoids contains a basic core of C6‐C3‐C6 of phenyl‐benzopyran backbone. The relative placement of the phenyl group on to the benzopyran core makes further classification into flavanoids, isoflavanoids and neoflavanoids. Flavans (2‐aryl chroman) are subclass of anthoxanthanes exhibits a broad spectrum of biological properties such as anti‐inflammatory, anti‐oxidant, and anti‐malarial properties. Some representative naturally occurring products possessing flavan core are apigenin, luteolin, tangeretin, scutellarein, etc. On the other hand, some of the notable isoflavan‐based natural products are glabridin and (S)‐(−)‐equol. Glabridin is isolated from Licorice roots, which regulates paraoxonase (PON2) levels. While the simple isoflavan (S)‐(−)‐equol, is produced from soy isoflavone intake. Also, natural products such as dalbergichromene, centchroman, and (+)‐myristinin A possess neoflavan (4‐aryl‐3,4‐dihydro‐2H‐chromenes) core structure. Owing to their broad biological and pharmacological properties, synthetic chemists are fascinated in developing new routes toward their synthesis. As a result, a decent number of reports have been established in the literature. Thus, for the past 5 years of time frame, many new methodologies have been witnessed, for the synthesis of various flavan systems. This review emphasizes most of the significant methods on accomplishing flavans, isoflavans and neoflavans and also focused on their applications to the synthesis of relevant natural as well as biologically active products.

Effect of isoflavones on breast cancer cell development and their impact on breast cancer treatments.

Epidemiological studies have suggested that intake of soy isoflavones is associated with a reduced risk of development of breast cancer and an improved prognosis in patients with breast cancer. In addition, basic research has demonstrated the antitumor effects of these compounds on breast cancer cell lines. However, the detailed effects of the intake of equol, which is one of the metabolites of the soy isoflavones, are yet to be clarified on the risk of development and recurrence of breast cancer and its interactions with drugs used for treating breast cancer. This study aimed to determine the antitumor effects of equol and investigate the impact of adding equol to therapeutic agents for breast cancer using breast cancer cell lines. We examined the antitumor effect of equol on breast cancer cell lines using MTS assay. We also studied the combined effect of equol and the existing hormonal or chemotherapeutic agents using combination index. We evaluated the expressions of the related proteins by Western blot analysis and correlated the findings with the antitumor effect. Equol showed bi-phasic protumor and antitumor effects; at a low concentration, it promoted the tumor growth in hormone receptor-positive cell lines, whereas antitumor effects were generally observed when an excessive amount of dose unexpected in the blood and the tissue was administered. When used with tamoxifen, equol might have some antagonistic effect, although it depends on equol concentration and the type of cancer cells. We confirmed that equol has dual action, specifically a tumor growth-promoting effect and an antitumor effect. Although the results suggested that equol might exert an antagonistic effect against tamoxifen depending on the concentration, equol did not exert an antagonistic effect on other therapeutic agents.

Soy and isoflavone consumption and subsequent risk of prostate cancer mortality: the Japan Public Health Center-based Prospective Study.

Although many epidemiological studies have reported the preventive effects of soy products and isoflavones on prostate cancer, our previous studies reported that the association between soy and isoflavones and prostate cancer incidence differed according to stage. It is more important to identify modifiable risk factors related to lethal prostate cancer. Here, we investigated the association between soy, soy products and isoflavones intake and prostate cancer mortality, in a prospective study in Japan. We conducted a population-based prospective study in 43580 Japanese men with no history of cancer or cardiovascular disease (aged 45-74 years). Participants completed a validated questionnaire which included 138 food items. We followed participants from 1995 to 2016. Hazard ratios (HRs) and 95% confidence intervals (CIs) of prostate cancer mortality were calculated according to quintiles of soy products and isoflavones intake, using Cox hazard proportional hazards regression. During 16.9 years follow-up, we registered 221 deaths from prostate cancer. Isoflavones and soy products intake was associated with an increased risk of prostate cancer death, with multivariate HRQ5 vs. Q1=1.39, 95% CI = 0.87-2.20, p for trend = 0.04 for isoflavones and multivariate HRQ5 vs. Q1=1.76, 95% CI = 1.10-2.82, p for trend = 0.04 for soy food. Our study suggested that high intake of soy and isoflavones might increase the risk of prostate cancer mortality.

Soy Intake and Colorectal Cancer Risk: Results from a Pooled Analysis of Prospective Cohort Studies Conducted in China and Japan

Soy is commonly consumed in east Asian countries and is suggested to reduce colorectal cancer (CRC) risk. However, results from epidemiologic studies are inconsistent, despite the anti-inflammatory and antiproliferative properties of soy isoflavones and soy protein. We evaluated the association between soy isoflavones and soy protein and CRC risk using 4 prospective cohort studies from China and Japan. Data were pooled from the Shanghai Women's Health Study (SWHS), Shanghai Men's Health Study (SMHS), Japan Public Health Center-based Prospective Study Cohort 1 (JPHC1), and Cohort 2 (JPHC2). Cox proportional hazards models estimated HRs and corresponding 95% CIs for the association of soy protein and isoflavone intake with CRC risk. The study included 205,060 individuals, among whom 2971 were diagnosed with incident CRC over an average follow-up of 12.7 y. No statistically significant associations with CRC risk were observed for soy protein or isoflavone intake. No association was observed among ever smokers consuming higher isoflavones (HRisoflavones: 0.83; 95% CI: 0.68, 1.00) and soy protein (HRsoy protein: 0.81; 95% CI: 0.39, 1.10). However, risk reductions were observed among premenopausal women with a body mass index [BMI (kg/m2)] <23.0 at baseline for higher isoflavone (HRisoflavones: 0.58, 95% CI: 0.34, 0.98). No evidence for an overall reduction in CRC risk by increasing soy food intake (i.e., protein or isoflavones) was observed. However, the association between soy and CRC risk may vary by BMI, smoking, and menopausal status among women. Future investigations are needed to further understand the biologic mechanisms observed.

Age-specific incidence rates of breast cancer among Japanese women increasing in a conspicuous bimodal distribution pattern

Breast cancer incidence rates are increasing in East and Southeast Asia, along with the westernisation of reproductive and lifestyle patterns. Such westernisation is thought to be involved in the cumulative exposure of breast tissue to both endogenous and exogenous oestrogen. Immigrant studies among Asian American women indicate that risk factors for breast cancer can be modified. When breast cancer incidence rates were compared with those of corpus uteri and colon among Japanese women in 2005, 2010 and 2015, it is of note that age-specific incidence rates of breast cancer in 5-year age groups clearly increased during the 10-year period in a bimodal distribution pattern, with two peaks in the 45–49 and 60–64 years age groups. From the relevant literature, it is inferred that the low prevalence of obesity and the intake of soy products or isoflavones among Japanese women may contribute to the bimodal distribution pattern by suppressing the extent of increase in breast cancer incidence rates among Japanese postmenopausal women. With regard to dietary habits relating to obesity, it has been globally reported that the intake of high-calorie foods is associated with the incidence of oestrogen receptor-positive breast cancer in both pre- and postmenopausal women, while high-carbohydrate or -milk intake that can enhance the secretion of insulin or insulin-like growth factor 1 is associated with that of oestrogen receptor-negative breast cancer mostly in postmenopausal women. Studies are needed to clarify the aetiology or modifiable factors behind the bimodal incidence rates of breast cancer among Japanese women.

Validation of soy isoflavone intake and its health effects: a review of the development of exposure biomarkers.

BACKGROUND/OBJECTIVESIt is difficult to consistently demonstrate the health effects of soy isoflavones owing to the multitude of factors contributing to their bioavailability. To accurately verify these health effects, dietary isoflavone intake should be measured using a biologically active dose rather than an intake dose. This concept has been expanded to the development of new exposure biomarkers in nutrition research. This review aims to provide an overview of the development of exposure biomarkers and suggest a novel research strategy for identifying the health effects of soy isoflavone intake.MATERIALS/METHODSWe cover recent studies on the health effects of soy isoflavones focusing on isoflavone metabolites as exposure biomarkers.RESULTSCompared to non-fermented soy foods, fermented soy foods cause an increased concentration of isoflavones in the biofluid immediately following ingestion. The correlation between exposure biomarkers in blood and urine and the food frequency questionnaire was slightly lower than that of corresponding 24-h dietary recalls. Urinary and blood isoflavone levels did not show a consistent association with chronic disease and cancer risk.CONCLUSIONIt is crucial to understand the variable bioavailabilities of soy isoflavones, which may affect evaluations of soy isoflavone intake in health and disease. Further studies on the development of valid exposure biomarkers are needed to thoroughly investigate the health effects of isoflavone.

Soy consumption and incidence of gestational diabetes mellitus: the Japan Environment and Children's Study.

Intervention studies have shown that isoflavone treatment improved glucose metabolism, indicating that soy intake may have a potential role in diabetes prevention. We aimed to investigate the prospective association of soy isoflavone and soy food intakes with incidence of gestational diabetes mellitus (GDM) in a birth cohort study. We recruited 97,454 pregnant women (median gestational age 12weeks) between January 2011 and March 2014. Dietary intakes during the 12months preceding study enrollment were assessed by a semi-quantitative food frequency questionnaire. The relative risks of GDM associated with soy isoflavone and soy food intakes were obtained by Poisson regression. Demographic information, histories of diseases, socioeconomic status, lifestyles, and dietary habits, obtained by a self-administrated questionnaire, were used for covariate adjustments. We identified 1904 cases of GDM (2.2%) among 84,948 women. Compared with those in the lowest quintile of soy isoflavone intake, women in the highest quintile were found to have experienced a significantly lower risk of GDM (multivariate relative risk = 0.82; 95% confidence interval: 0.70, 0.95; P for trend = 0.05). Similar results were observed for genistein and daidzein. Regarding soy foods, intakes of miso soup and natto were inversely associated with GDM incidence (both P for trend ≤ 0.01), whereas the association for tofu intake appeared to be nonlinear (P for trend = 0.74). Higher intakes of miso soup and natto before and during early pregnancy, compared with lower intakes, may be associated with a lower incidence of GDM.

Intake of Commercially Produced Fermented Soy Powder Q CAN PLUS® Favorably Changes Cholesterol and Isoflavone Intake in Individuals at High Risk of Cardiovascular Disease

Abstract Objectives Q CAN PLUS® is a fermented soy powder currently marketed in the US as a food product. We conducted a feeding trial to examine the effects of Q CAN PLUS® on the nutrient composition of the habitual diets of individuals at high risk of cardiovascular diseases. We hypothesized that the nutrient profile, particularly nutrients associated with CVD risk, differs among individuals in the Q CAN PLUS® phase compared to the placebo phase. Methods Study design was a randomized, controlled crossover intervention with twenty-four free living adults (29–75 years old; 80% female; 8% normal BMI, 45% overweight, 47% obese) at high risk of cardiovascular diseases. Subjects were randomized to receive either Q CAN PLUS® (fermented soy) powder or placebo powder for twelve weeks and switched over to the placebo treatment after two weeks of wash out period. Two 24-hour dietary recalls were collected during each phase which included one weekday and one weekend dietary recall. The nutrient consumption per day (mean ± SD) were based on a synthetic week by using the following formula: ((weekday * 5) +(weekday * 2))/7. Results On average, intake of cholesterol (211 ± 169 mg) was 13% lower (P = 0.05) in the Q CAN PLUS® phase compared to placebo (243 ± 179 mg). Total soy isoflavones (444 ± 210 mg) was 12 times higher (P &amp;lt; 0.0001) during Q CAN PLUS® phase than the placebo phase (33 ± 93 mg). Dietary total carbohydrate, total protein, vegetable protein, animal protein during Q CAN PLUS® phase were not statistically different from placebo phase. Conclusions The differences in the intake of cholesterol and total soy isoflavones may have implications on risk of cardiovascular diseases. Funding Sources BESO Biological Research Inc Diamond Bar, CA, USA.

Sex-specific associations of habitual intake of soy protein and isoflavones with risk of type 2 diabetes.

A possible mechanism by which intake of soy isoflavones leads to an improvement in glucose metabolism has been suggested. However, epidemiological evidence of a link between dietary soy isoflavone and type 2 diabetes is not convincing. This study aimed to evaluate the prospective associations between intake of dietary soy protein and isoflavones (total isoflavones, daidzein and genistein) and risk of type 2 diabetes in a community-based cohort of Korean adults aged≥40 years, the Korean Multi-Rural Communities Cohort (MRCohort). A total of 8269 participants who did not have type 2 diabetes were enrolled. Dietary intake was calculated using a food frequency questionnaire. Over 50,063 person-years of follow-up, 531 participants developed type 2 diabetes. Significant dose-response inverse associations were observed between dietary soy protein and isoflavones (quartiles) and type 2 diabetes in women (incidence rate ratio, IRR=0.63, 95% CI=0.45-0.87, P for trend=0.0078 for soy protein; IRR=0.62, 95% CI=0.45-0.86, P for trend=0.0031 for total isoflavones for the highest quartile compared with the lowest quartile). Similar significant linear trends were found for both daidzein and genistein. However, there were no significant associations with soy protein and isoflavones in men. The sex-specific differences in associations between soy protein and isoflavones intakes and type 2 diabetes risk were statistically significant (all P for interaction<0.05). Habitual intake of soy protein and isoflavones may be inversely associated with type 2 diabetes in women, but not in men. Dietary soy components may play different roles in the development of type 2 diabetes in men and women.

High dietary daidzein intake lowers cholesterol levels among post-menopausal women

BackgroundMenopause is associated with changes in metabolic profile. Although hormone replacement therapy (HRT) has been shown to have beneficial effects on lipid metabolism, its adverse effects have indicated a need for alternative estrogen-based treatments. Several investigations have evaluated the effects of isoflavones on serum lipid levels in postmenopausal women, but the results were ambiguous. The objective of this study was to determine the relationship of dietary daidzein, genistein, and glycitein levels with lipid profile in postmenopausal women.MethodsA cross-sectional study was conducted involving 186 post-menopausal women. A food recall questionnaire was used to measure dietary genistein, daidzein, and glycitein levels. Serum total cholesterol (TC), low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, and triacylglycerol (TAG) were measured using the enzymatic colorimetric method. Simple and multivariate linear regression were used to analyze the data.ResultsGenistein intake was significantly associated with TC (b=145.48, p=0.023) and HDL cholesterol levels (b=48.80, p=0.032). Daidzein intake was significantly associated with TC (b=-204.60, p=0.003), LDL cholesterol (b=-160.81, p=0.014) and HDL cholesterol levels (b=-67.118, p=0.032). Glycitein was not significantly associated with TC (b=232.78;p=0.133), HDL (b=43.59;p=0.428), and LDL (b=235.84;p=0.116). Dietary daidzein had a more lowering effect on TC (Beta=-2.80) and HDL cholesterol (Beta=-2.67) than had genistein on TC (Beta=2.66) and HDL cholesterol (Beta=2.03).ConclusionsHigh dietary daidzein level has a significant lowering effect on TC, LDL cholesterol and HDL cholesterol in post-menopausal women. Our study supports the advice given to the public to increase soy isoflavone intake in post-menopausal women.