Urinary Phytoestrogen Concentrations Research Articles

Associations of Urinary Phytoestrogen Concentrations with Nonalcoholic Fatty Liver Disease among Adults.

Phytoestrogens can alleviate some pathological processes related to nonalcoholic fatty liver disease (NAFLD). However, there are limited and contradictory studies on the relationships between phytoestrogens (especially single phytoestrogen) and NAFLD. The purpose of this study was to explore the relationships between urinary phytoestrogen concentrations and NAFLD in American adults. This cross-sectional study used the data of the National Health and Nutrition Examination Survey from 1999 to 2010, and 2294 adults were finally enrolled in this study. The concentrations of phytoestrogens were measured in urine samples, and urinary phytoestrogens were divided into tertiles according to the concentration distributions. The diagnosis of NAFLD was determined by the United States fatty liver index. The main analysis used a multivariate logistic regression model. The fully adjusted models included gender, age, race, education, marriage, poverty, body mass index, waist circumference, smoking, diabetes, hypertension, total cholesterol, high-density lipoprotein cholesterol, triglycerides, and other five phytoestrogens. In the fully adjusted model, the urinary enterolactone (ENL) concentration was negatively correlated with NAFLD (OR of Tertile 3 : 0.48, 95% CI 0.25–0.94). When stratified by age and gender, the urinary ENL concentration was negatively correlated with NAFLD in males aged 40–59 years (OR of Tertile 3 : 0.08, 95% CI 0.01–0.82), while the urinary equol concentration was positively correlated with NAFLD in such population (OR of Tertile 3 : 4.27, 95% CI 1.02–17.85). In addition, a negative correlation between enterodiol (END) concentration and NAFLD was observed in males aged 60 years or over (OR of Tertile 2 : 0.18, 95% CI 0.05–0.69). Collectively, in middle-aged males, urinary ENL may be associated with a lower risk of NAFLD, while urinary equol may be related to a higher risk. In addition, urinary END has a possible relationship with a reduced risk of NAFLD in elder males. Definitely, clinical randomized controlled trials are needed to further verify the conclusions.

Associations of Urinary Phytoestrogen Concentrations with Sleep Disorders and Sleep Duration among Adults.

Current evidence on the relationship of phytoestrogens with sleep is limited and contradictory. In particular, studies on individual phytoestrogens and sleep have not been reported. Thus, this study aimed to appraise the associations of individual phytoestrogens with sleep disorders and sleep duration. This cross-sectional study comprising 4830 adults utilized data from the National Health and Nutrition Examination Survey 2005–2010. Phytoestrogens were tested in urine specimens. Sleep disorders and sleep duration were based on a self-reported doctor’s diagnosis and usual sleep duration. The main analyses utilized logistic and multinomial logistic regression models and a restricted cubic spline. In the fully adjusted model, compared with tertile 1 (lowest), the odds ratios (95% confidence intervals (CIs)) of sleep disorders for the highest tertile of urinary concentrations of enterolactone, enterodiol, and O-desmethylangolensin were 0.64 (0.41–1.00), 1.54 (1.07–2.21), and 1.89 (1.26–2.85), respectively. Linear inverse, approximatively linear positive, and inverted L-shaped concentration–response relationships were found between enterolactone, enterodiol, and O-desmethylangolensin and sleep disorders, respectively. Compared with normal sleep (7–8 h/night), the relative risk ratio (RRR) (95% CI) of very short sleep for enterolactone was 0.56 (0.36–0.86), and the RRR (95% CI) of long sleep risk for genistein was 0.62 (0.39–0.99). Furthermore, negative associations of genistein with sleep disorders and enterolactone with long sleep risk, as well as positive associations of enterodiol with both long and very short sleep, were observed in the stratified analysis by age or gender. Finally, a notable finding was that urinary O-desmethylangolensin concentration was positively related to sleep disorders in both females aged 40–59 years and non-Hispanic Whites but inversely associated with sleep disorders in both females aged 60 years or over and other Hispanics. Our findings suggested that enterolactone and genistein might be beneficial for preventing sleep disorders or non-normal sleep duration among adults, and enterodiol might be adverse toward this goal. However, the association of O-desmethylangolensin with sleep disorders might be discrepant in different races and females of different ages.

GENDER DIFFERENCES IN PHYTOESTROGEN INTAKE AND SPEED OF PROCESSING PERFORMANCE IN OLDER ADULTS

Phytoestrogen consumption mimics estrogen in the body, albeit to a much smaller scale, and therefore represent a potential dietary intervention to supplement estrogen loss or hormonal changes. Additionally, studies have reported that phytoestrogens may benefit cognitive health, although this may differ among males and females in older adults due to differences in absorption, hormones, and age-related changes. In the current study, urinary phytoestrogen concentrations (covariate-adjusted standardized for urinary creatinine) and gender were used as predictors to examine differences in relation to speed of processing (SOP) measured by the Digit Symbol Substitution Test (DSS). Participants were drawn from The National Health and Nutrition Examination Survey (NHANES 1999–2002) and consisted of 354 individuals ranging from 65 to 85 years old. A multiple regression analysis included covariates; age, BMI, race, education, smoking, socioeconomic status, and urinary creatinine. Among the individual phytoestrogens, genistein demonstrated significant gender differences relating to SOP. Females scored higher on the DSS with increased amounts of genistein while demonstrating the opposite for males. Interestingly, for the overall lignan predictor, higher lignans were associated with better SOP performance in males but lower SOP performance in females. Overall, females scored higher on the DSS compared to males regardless of the number of phytoestrogens. Results suggest that there are significant gender differences in both the predictors of genistein and lignan consumption. Both yielded different associations demonstrating the potential impact that specific phytoestrogens may have on cognitive aging depending on gender. To become a viable intervention, further research on these gender differences are needed.

Association between Dietary Share of Ultra-Processed Foods and Urinary Concentrations of Phytoestrogens in the US.

The aim of this study was to examine the relationship between dietary contribution of ultra-processed foods and urinary phytoestrogen concentrations in the US. Participants from cross-sectional 2009–2010 National Health and Nutrition Examination Survey aged 6+ years, selected to measure urinary phytoestrogens and with one 24-h dietary recall were evaluated (2692 participants). Food items were classified according to NOVA (a name, not an acronym), a four-group food classification based on the extent and purpose of industrial food processing. Ultra-processed foods are formulations manufactured using several ingredients and a series of processes (hence “ultra-processed”). Most of their ingredients are lower-cost industrial sources of dietary energy and nutrients, with additives used for the purpose of imitating sensorial qualities of minimally processed foods or of culinary preparations of these foods. Studied phytoestrogens included lignans (enterolactone and enterodiol) and isoflavones (genistein, daidzein, O-desmethylangolensin and equol). Gaussian regression was used to compare average urinary phytoestrogen concentrations (normalized by creatinine) across quintiles of energy share of ultra-processed foods. Models incorporated survey sample weights and were adjusted for age, sex, race/ethnicity, family income, and education, among other factors. Adjusted enterodiol geometric means decreased monotonically from 60.6 in the lowest quintile to 35.1 µg/g creatinine in the highest, while adjusted enterolactone geometric means dropped from 281.1 to 200.1 across the same quintiles, respectively. No significant linear trend was observed in the association between these quintiles and isoflavone concentrations. This finding reinforces the existing evidence regarding the negative impact of ultra-processed food consumption on the overall quality of the diet and expands it to include non-nutrients such as lignans.

Urinary Phytoestrogen Concentrations Are Not Associated with Incident Endometriosis in Premenopausal Women

BackgroundPhytoestrogens have been associated with subtle hormonal changes, but their effects on endometriosis are largely unknown. ObjectiveWe assessed the association between urinary concentrations of phytoestrogens and incident endometriosis. MethodsWe included an operative sample of 495 premenopausal women aged 18–44 y undergoing laparoscopies and laparotomies at 14 clinical sites between 2007 and 2009 and a general population sample of 131 women from the same geographic area who were matched on age and menstruation status. Endometriosis in the surgical sample was assessed by surgical visualization (clinical gold standard), whereas disease in the general population sample was assessed with the use of a pelvic MRI. Urine concentrations of genistein, daidzen, O-desmethylangolensin, equol, enterodiol, and enterolactone were measured at baseline. Poisson regression with robust error variance was used to estimate the risk of an endometriosis diagnosis for each sample after adjusting for age and body mass index (in kg/m2). Separate models were run for each phytoestrogen. ResultsOverall geometric mean urine concentrations of phytoestrogens were as follows: genistein [88 nmol/L (95% CI: 72, 108 nmol/L)], daidzein [194 nmol/L (95% CI: 160, 236 nmol/L)], O-desmethylangolensin [4 nmol/L (95% CI: 3, 6 nmol/L)], equol [4 nmol/L (95% CI: 4, 6 nmol/L)], enterodiol [29 nmol/L (95% CI: 22, 38 nmol/L)], and enterolactone [355 nmol/L (95% CI: 395, 544 nmol/L)]. Geometric mean concentrations of phytoestrogens did not significantly differ by endometriosis status in either sample. Adjusted RRs for endometriosis ranged from 0.87 to 1.09 for the 6 phytoestrogens measured, with all CIs including a value ≥1. Phytoestrogens were not associated with the severity of endometriosis when restricting the analysis to women with moderate-to-severe disease per the revised American Society for Reproductive Medicine criteria. Furthermore, no associations were observed between self-reported high soy intake and endometriosis. ConclusionsDespite endometriosis being an estrogen-dependent disease, we found no evidence that urinary phytoestrogens were associated with a higher risk of an endometriosis diagnosis in either a sample of premenopausal women or in a surgical sample.

Urinary Phytoestrogens Are Associated with Subtle Indicators of Semen Quality among Male Partners of Couples Desiring Pregnancy1–3

Background: Phytoestrogens have been associated with subtle hormonal changes, although effects on male fecundity are largely unknown.Objective: We evaluated associations between male urinary phytoestrogen (isoflavone and lignan) concentrations and semen quality.Methods: This study was a prospective cohort study of 501 male partners of couples desiring pregnancy and discontinuing contraception. Each participant provided up to 2 semen samples that were analyzed for 35 semen quality endpoints the following day. Linear mixed-effects models were used to estimate associations between baseline urinary phytoestrogen concentrations and semen quality parameters, adjusted for age, body mass index (BMI), research site, and serum lipid and cotinine concentrations.Results: Most associations between urinary phytoestrogens and semen quality parameters were null. However, select individual phytoestrogens were associated with semen quality parameters, with associations dependent on the class of phytoestrogens and modified by BMI. Specifically, genistein and daidzein were associated with a lower percentage of normal sperm and increased abnormalities in semen morphology, with reduced associations observed as BMI increased (P < 0.05) [percentages (95% CIs) of normal morphology by WHO traditional criteria: genistein, main effect: −5.61% (−9.42%, −1.79%); interaction: 0.19% (0.06%, 0.31%) per log unit increase; daidzein, main effect: −5.35% (−9.36%, −1.34%); interaction: 0.18% (0.05%, 0.32%) per log unit increase]. Enterolactone was associated with fewer abnormalities in semen morphometry and morphology and decreased DNA fragmentation, with reduced associations observed as BMI increased (P < 0.05) [percentages (95% CIs) of abnormalities in the neck and midpiece: enterolactone, main effect: −3.35% (−6.51%, −0.19%); interaction: 0.11% (0.01%, 0.21%) per log unit increase].Conclusions: These results suggest that male urinary phytoestrogen concentrations characteristic of the US population may be associated with subtle indicators of male fecundity and semen quality but were not associated with couple fecundity.

Urinary Concentrations of Phytoestrogens Are Not Associated with Risk of Type 2 Diabetes: The Singapore Chinese Health Study

ObjectiveWe evaluated the relation between urine concentrations of phytoestrogens and risk of incident type 2 diabetes (T2D) in middle‐aged and older Chinese.Methods: Urine phytoestrogen metabolites (including isoflavones and lignans) were assayed by HPLC among 564 T2D cases and 564 controls in a nested case‐control study within the Singapore Chinese Health Study. Morning urine samples were collected from participants free of diagnosed diabetes, cardiovascular disease and cancer (1999‐2004). Incident self‐reported T2D cases were identified during the follow‐up at 2006‐2010, and controls were matched for age and date of urine collection, sex and dialect group.Results: The multivariate‐adjusted odds ratios (ORs) and 95% confidence intervals (CIs) across quartiles of urine isoflavones were 1.00, 0.76 (0.52‐1.11), 0.78 (0.53‐1.14) and 0.79 (0.54‐1.15), respectively (P‐trend=0.54); and the ORs (95% CIs) for lignans were 1.00, 0.87 (0.60‐1.27), 1.10 (0.77‐1.56) and 0.93 (0.63‐1.37), respectively (P‐trend=0.93). No significant associations were found for individual metabolite of isoflavones (genistein, daidzein, glycetin, and equol) or lignans (enterodiol and enterolactone).ConclusionsThe present study did not find a significant relation between urine concentrations of phytoestrogen metabolites andT2D risk in Chinese population.Funding sources: The study was supported by NIH R01 CA144034 and UM1 CA182876, and Singapore Tier 1 grant.

OP2-02 URINARY PHYTOESTROGENS ARE ASSOCIATED WITH LOWER URINARY TRACT SYMPTOMS IN WOMEN

You have accessJournal of UrologyOutstanding Posters: Benign Disease1 Apr 2014OP2-02 URINARY PHYTOESTROGENS ARE ASSOCIATED WITH LOWER URINARY TRACT SYMPTOMS IN WOMEN Evgeniy Kreydin, Glen Barrisford, Dayron Rodriguez, Yahir Santiago-Lastra, Alejandro Sanchez, Mark Preston, Hillary Keenan, and Dicken Ko Evgeniy KreydinEvgeniy Kreydin More articles by this author , Glen BarrisfordGlen Barrisford More articles by this author , Dayron RodriguezDayron Rodriguez More articles by this author , Yahir Santiago-LastraYahir Santiago-Lastra More articles by this author , Alejandro SanchezAlejandro Sanchez More articles by this author , Mark PrestonMark Preston More articles by this author , Hillary KeenanHillary Keenan More articles by this author , and Dicken KoDicken Ko More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.2552AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Phytoestrogens are a class of plant-derived compounds that have selective estrogen receptor modulator properties. Links have been established between urinary phytoestrogen levels and a number of sex hormone-dependent pathologic states, such as breast and endometrial cancer, vaginal atrophy and osteoporosis. We examined whether urinary levels of isoflavone-type (daidzein, o-desmethylangolensin, equol, and genistein) and lignan-type phytoestrogens (enterodiol and enterolactone) were associated with urinary symptoms in women. METHODS National Health and Nutrition Examination Survey (NHANES) data collected from 2000 to 2010 was used to identify cohorts of 4104, 1648, and 2161 women, who responded to urinary incontinence, nocturia, and urinary symptom bother questionnaires, respectively. Urinary phytoestrogen levels were log transformed. Association between phytoestrogen levels, urge incontinence, stress incontinence, nocturia, bother from urinary incontinence, and the degree of effect of urinary incontinence on daily living was assessed using weighted multivariate logistic regression adjusting for age, race, smoking status, body mass index, diabetes, parity, and menopausal status. RESULTS Increasing concentration of lignan phytoestrogens enterolactone and enterodiol was associated with decreased likelihood of urge incontinence, bother from incontinence, and effect of urinary incontinence on daily living (p < 0.05). Increasing concentration of enterolactone was also associated with decreased likelihood of nocturia (p < 0.05). None of the isoflavone phytoestrogens were associated with urinary symptoms. Odds ratios per unit change in phytoestrogen concentration are given in Table 1. CONCLUSIONS This is the first study to demonstrate an association between urinary phytoestrogen levels and urinary symptoms in a large population-based cohort of women. We demonstrate that members of the lignan phytoestrogen family may have a protective effect on urinary symptoms in women. Prospective clinical and laboratory studies are warranted to investigate the mechanism of this relationship. Table 1. Odds ratios and 95% confidence intervals for urinary symptoms per unit change in urinary phytoestrogen concentrations. Phytoestrogen Type Phytoestrogen Urge Incontinence Nocturia Incontinence Bother Incontinence Effect on Daily Activities Isoflavone Daidzein 1.01 (0.95-1.07) 0.99 (0.89-1.09) 1.04 (0.97-1.12) 1.02 (0.90-1.15) Isoflavone O-Desmethylangolensin 1.02 (0.98-1.07) 0.95 (0.87-1.03) 1.02 (0.97-1.07) 0.96 (0.86-1.04) Isoflavone Equol 0.95 (0.88-1.02) 1.06 (0.89-1.25) 1.02 (0.94-1.11) 0.88 (0.74-1.05) Isoflavone Genistein 0.88 (0.47-1.62) 1.03 (0.93-1.15) 1.08 (0.95-1.17) 1.54 (0.43-5.41) Lignan Enterodiol 0.93 (0.88-0.98)∗ 1.03 (0.90-1.17) 0.92 (0.85-0.99)∗ 0.86 (0.77-0.96)∗ Lignan Enterolactone 0.95 (0.89-0.99)∗ 0.86 (0.76-0.97)∗ 0.92 (0.86-0.98)∗ 0.90 (0.81-0.99)∗ ∗p < 0.05 © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e387 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Evgeniy Kreydin More articles by this author Glen Barrisford More articles by this author Dayron Rodriguez More articles by this author Yahir Santiago-Lastra More articles by this author Alejandro Sanchez More articles by this author Mark Preston More articles by this author Hillary Keenan More articles by this author Dicken Ko More articles by this author Expand All Advertisement Advertisement PDF DownloadLoading ...

Combined effects of urinary phytoestrogens metabolites and polymorphisms in metabolic enzyme gene on idiopathic male infertility

Phytoestrogens are plant-derived compounds that may interact with estrogen receptors and mimic estrogenic effects. It remains unclear whether the individual variability in metabolizing phytoestrogens contributes to phytoestrogens-induced beneficial or detrimental effects. Our aim was to determine whether there is any interaction between metabolic rates (MR) of phytoestrogens and genetic polymorphisms in related xenobiotic metabolizing enzyme genes. MR was used to assess phytoestrogen exposure and individual metabolic ability. The amount of phytoestrogens in urine was measured by ultra-high performance liquid chromatography-tandem mass spectrometry in 600 idiopathic infertile male patients and 401 controls. Polymorphisms were genotyped using the SNPstream platform combined with the Taqman method. Prototypes and metabolites of secoisolariciresinol (SEC) have inverse effects on male reproduction. It was found that low MR of SEC increased the risk of male infertility (OR 2.49, 95 % CI 1.78, 3.48, P trend = 8.00 × 10(-8)). Novel interactions were also observed between the MR of SEC and rs1042389 in CYP2B6, rs1048943 in CYP1A1, and rs1799931 in NAT2 on male infertility (P inter = 1.06 × 10(-4), 1.14 × 10(-3), 3.55 × 10(-3), respectively). By analyzing the relationships between urinary phytoestrogen concentrations, their metabolites and male infertility, we found that individual variability in metabolizing SEC contributed to the interpersonal differences in SEC's effects on male reproduction.

Urinary phytoestrogens and depression in perimenopausal US women: NHANES 2005–2008

BackgroundFluctuating hormonal levels observed during the menopausal transition may increase vulnerability to depression in susceptible women. Thus, it is of interest to examine the effect of natural estrogens such as phytoestrogens on the risk of depression in perimenopausal women. MethodsOur analysis included 193 perimenopausal women of the National Health and Nutrition Survey (NHANES) 2005–2008 aged 45–55 years. Urinary concentrations of phytoestrogens (isoflavones and lignans) were measured by HPLC-APPI-MS/MS. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9). Logistic regression models examined the association of phytoestrogens concentrations (creatinine-standardized and log-transformed) with depression (yes/no). ResultsUnadjusted odds ratios (OR) of the associations between urinary phytoestrogen concentrations and perimenopausal depression were below 1; however, only lignans were significantly inversely associated with depression. The latter findings were not attenuated in multivariate analysis including age, race, body mass index, poverty income ratio, smoking, alcohol consumption, cancer, diabetes, and cardiovascular disease (lignans: OR=0.66; 95% confidence intervals (CI) 0.50–0.87, enterodiol: OR=0.63; 95% CI 0.51–0.78, enterolactone: OR=0.75; 95% CI 0.60–0.93). LimitationsOur cross-sectional study design does not allow for causal inferences. Because information to precisely assess perimenopausal symptoms was missing, we defined perimenopause based on women's age. ConclusionsLower lignans but not isoflavones concentrations were statistically significantly associated with an increased risk of depression in perimenopausal women. Because of medical risks associated with the use of hormone therapy, further investigation on the effect of lignans on the risk of depression in perimenopausal women is warranted.

Association of Urinary Phytoestrogen Concentrations with Serum Concentrations of Prostate-Specific Antigen in the National Health and Nutrition Examination Survey

Some clinical trials have shown that high phytoestrogen intake may decrease serum concentrations of prostate-specific antigen (PSA), and phytoestrogens may also lower prostate cancer risk. It was the aim of this study to examine the relationship between the serum PSA level and urine phytoestrogen concentration in generally healthy U.S. men. Eight hundred twenty-four men, 40+ yr old without prostate cancer, who participated in the 2001–2004 NHANES surveys, were included in the analysis. The association of total PSA, free PSA, and PSA ratio [free PSA/total PSA * 100] with concentrations of isoflavones and lignans (standardized for urinary creatinine concentration) was examined using multivariable-adjusted linear and logistic regression models. The linear regression analyses showed no clear association between creatinine-standardized urinary phytoestrogen concentrations and serum total or free PSA levels or PSA ratio. However, the odds of having a PSA ratio <15% rose from Quartile 1 to Quartile 4 of isoflavone excretion (odds ratio = 2.82, 95% confidence interval 1.28–6.22 for top vs. bottom quartile), but there were no associations with having a PSA ratio <25%. In generally healthy U.S. men, 40+ yr old without a diagnosis of prostate cancer, urinary isoflavone, and lignan concentrations were not associated with serum PSA level.

Urinary phytoestrogens and risk of prostate cancer in Jamaican men

We evaluated the relationship of spot urinary concentrations of phytoestrogens with total prostate cancer and tumor grade in a hospital-based case-control study in Jamaica. Urine samples were analyzed for genistein, daidzein, equol (isoflavones), and enterolactone (lignan) among newly diagnosed cases (n = 175) and controls (n = 194). Urinary concentrations of enterolactone (lignan) were higher among cases. There were no significant differences in median concentrations of isoflavone excretion. Compared with non-producers of equol (reference tertile), men who produced equol were at decreased risk of total prostate cancer (tertile 2: OR, 0.42; CI, 0.23-0.75) (tertile 3: OR, 0.48; CI, 0.26-0.87) (p (trend), 0.020) and high-grade disease (tertile 2: OR, 0.31; CI, 0.15-0.61) (tertile 3: OR, 0.29; CI, 0.13-0.60) (p (trend), 0.001). Higher concentrations of enterolactone were positively related to total prostate cancer (OR, 1.85; CI, 1.01-3.44; p (trend), 0.027) as well as high-grade disease (OR, 2.46; CI, 1.11-5.46; p (trend), 0.023). There were no associations between urinary excretion of genistein and daidzein with risk of prostate cancer. Producers of equol (isoflavone) may be at reduced risk of total- and high-grade prostate cancer whereas enterolactone may increase the likelihood of disease.

Baseline Urinary Phytoestrogen Levels and the Natural History of Untreated, Localised Prostate Cancer in a British Population

To determine whether urinary concentrations of phytoestrogens are associated with the rate of disease progression in men with untreated, localised prostate cancer. Patients with untreated, localised prostatic adenocarcinoma on a prospective clinical study of active surveillance had urine samples collected at baseline. Patients underwent monitoring with serial PSA levels and repeat octant prostate biopsies. Disease progression was defined as either adverse histology on repeat biopsy (primary Gleason grade >or= 4, or >50% positive cores) or radical treatment for PSA velocity >1 ng/mL/year. Time to disease progression was analysed with respect to baseline urinary levels of genistein, enterolactone, daidzein and equol, assayed using liquid chromatography/tandem mass spectrometry. 191 patients were evaluable, with a median follow-up of 2.5 years. 71 patients experienced disease progression. No significant association was seen between time to disease progression and baseline urinary levels of daidzein (p=0.85), genistein (p=0.81), enterolactone (p=0.085) or equol (p=0.33). No significant association was seen between adverse histology on repeat biopsy and urinary levels of either daidzein (p=0.85), genistein (p=0.58), enterolactone (p=0.88) or equol (p=0.71). There was no significant correlation between PSA velocity and urinary levels of daidzein (p=0.90), genistein (p=0.98), enterolactone (p=0.10) or equol (p=0.60). These data do not support the hypothesis that phytoestrogens prevent disease progression in men with localised prostate cancer.

Baseline urinary phytoestrogen levels and the natural history of untreated, localised prostate cancer in a British population

To determine whether urinary concentrations of phytoestrogens are associated with the rate of disease progression in men with untreated, localised prostate cancer. Patients with untreated, localised prostatic adenocarcinoma on a prospective clinical study of active surveillance had urine samples collected at baseline. Patients underwent monitoring with serial PSA levels and repeat octant prostate biopsies. Disease progression was defined as either adverse histology on repeat biopsy (primary Gleason grade >or= 4, or >50% positive cores) or radical treatment for PSA velocity >1 ng/mL/year. Time to disease progression was analysed with respect to baseline urinary levels of genistein, enterolactone, daidzein and equol, assayed using liquid chromatography/tandem mass spectrometry. 191 patients were evaluable, with a median follow-up of 2.5 years. 71 patients experienced disease progression. No significant association was seen between time to disease progression and baseline urinary levels of daidzein (p=0.85), genistein (p=0.81), enterolactone (p=0.085) or equol (p=0.33). No significant association was seen between adverse histology on repeat biopsy and urinary levels of either daidzein (p=0.85), genistein (p=0.58), enterolactone (p=0.88) or equol (p=0.71). There was no significant correlation between PSA velocity and urinary levels of daidzein (p=0.90), genistein (p=0.98), enterolactone (p=0.10) or equol (p=0.60). These data do not support the hypothesis that phytoestrogens prevent disease progression in men with localised prostate cancer.

Urinary phytoestrogen concentrations in the U.S. population (1999–2000)

We report population-based urinary concentrations of phytoestrogens stratified by age, sex, and composite racial/ethnic variables. We measured the isoflavones - genistein, daidzein, equol, and O-desmethylangolensin (O-DMA) - and the lignans - enterolactone and enterodiol - in approximately 2500 urine samples from individuals aged 6 years and older who participated in the National Health and Nutrition Examination Survey (NHANES) in 1999 and 2000. We detected all phytoestrogens in over 70% of the samples analyzed; enterolactone was detected in the highest concentrations, and daidzein was detected with the highest frequency. The geometric means for each phytoestrogen were as follows: genistein, 22.3 microg/g; daidzein, 68.6 microg/g; equol, 7.65 microg/g; O-DMA, 3.95 microg/g; enterolactone, 217 microg/g; and enterodiol, 24.3 microg/g creatinine. The 95th percentiles for each phytoestrogen were as follows: genistein, 380 microg/g; daidzein, 944 microg/g; equol, 50.3 microg/g; O-DMA, 217 microg/g; enterolactone, 2240 microg/g; and enterodiol, 240 microg/g creatinine. Multivariate analyses showed statistically significant differences among many of the demographic subgroups. Adolescents had higher concentrations of genistein and equol than adults. Non-Hispanic whites had higher concentrations of enterodiol and equol than Mexican Americans or non-Hispanic blacks. Non-Hispanic whites also had higher concentrations of enterolactone and O-DMA than Mexican Americans. Mexican Americans had higher concentrations of genistein than non-Hispanic blacks; however, the opposite was found for O-DMA. Determination of phytoestrogen exposure in the US population will help us to better understand phytoestrogen consumption in the US and will assist us in elucidating the potential role of phytoestrogens in protecting against cancer and heart disease.

Effects of dietary phytoestrogens in postmenopausal women

The aim of this study was to test the hypothesis that increased dietary intake of phytoestrogens reduces the health impact of the menopause. To test this hypothesis, a double-blind, randomized, entry-exit, cross-over study was conducted to assess the effects of three dietary manipulations - soy and linseed diets (high in phytoestrogens) and a wheat diet (low in phytoestrogens). Postmenopausal women were recruited and randomly assigned to one of the three dietary regimens. Urinary phytoestrogen concentrations, hot flush rate, vaginal smears, bone mineral density and bone mineral content were assessed for two 12-week periods. Comparative analysis showed no significant differences, but, when analyzed separately, groups consuming high phytoestrogen diets had between 10 and 30 times higher urinary excretion of phytoestrogens compared to those consuming the low phytoestrogen diet (p<0.01). Study participants consuming soy, linseed and wheat diets had a 22% (not significant, n.s.), 41% (p < 0.009) and 51% [p < 0.001) reduction in hot flush rate; a 103% (p < 0.04), 5.5% (n.s.) and 11% (n.s.) increase in vaginal cytology maturation index; and a 5.2% (p < 0.04), 5.2% (n.s.) and 3.8% (n.s.) increase in bone mineral content, respectively. No changes were detected in bone mineral density. The differential effects of high phytoestrogen dietary manipulations on outcomes may represent tissue-specific responses to isoflavones and lignans contained in soy and linseed, respectively. Whilst health outcome measures were not significantly different between groups, the data obtained from separate analysis suggest that phytoestrogens in soy and linseed may be of use in ameliorating some of the symptoms of menopause. Furthermore, the significant decrease in hot flush rate in the wheat group cannot be attributable to phytoestrogens measured in this study. Due to subject variability, larger studies are still needed to evaluate population benefit.