## 4 Discussion  
The effects of phytoestrogens are very varied [23], with the following properties described: anticancer effects [25], cardiotonic effects attributed to the flavonoid quercetin and, to a lesser extent, to genistein and lutein [54], improving the resistance of capillaries and helping prevent them from breaking (hesperidin, rutin, and quercetin) [55], the ability to prevent the formation of thrombi in blood vessels, and the ability to lower the concentration of cholesterol and triglycerides [25; 56]; hesperidin has anti-inflammatory and analgesic properties [57], but only its antioxidant effect has been demonstrated with persistent results [36] in addition to estrogenic/anti-estrogenic effects [34]. The dietary intake of phytoestrogens has been reported to be <1 mg day\({}^{-1}\) in Europe and the United States [44; 58] and considerably higher (>20 mg day\({}^{-1}\)) in Japan and Korea, attributable to the elevated consumption of soy derivatives such as natto, miso, and tofu [59; 60; 61; 62]. Our research group has published numerous studies on the estrogenic effects of natural and synthetic molecules in foods, especially vegetables. Many of these molecules have been classified as endocrine disrupters after analyses of their behavior in biological media in vitro or in vivo [3; 15; 17; 45]. There has been considerable research on the hormonal effects of phytoestrogens and interest in their intake in the diet or as supplements. We describe here a technique to estimate the estrogenic effect of diet as a function of its phytoestrogen content using a food frequency questionnaire (FFQ) to collect data on the dietary intake of phytoestrogens and apply the E-screen test to establish the estrogenicity of the phytoestrogens consumed. The diet of this population of Mexican women was estimated to have a mean total estrogenic capacity of 0.129 \(\times\) 10\({}^{-10}\) eq.E2 (12.9 pmol day\({}^{-1}\)). The mean was elevated and equivalent to the hormonal capacity of individuals who produce between 0.3 and 14 pmol day\({}^{-1}\) according to age and other factors [63]. Regarding the estrogenic effect, the effects of this additional burden are highly controversial, and no definitive conclusion has been reached. Exposure to the estrogenic activity of these chemicals can be positive or negative, and exposure is considered a risk at any age [64; 65; 66]. However, many phytoestrogens are \begin{table}
\begin{tabular}{c c c c c c} \hline  & **Mean** & **Median** & **SD** & **Minimum** & **Maximum** \\ \hline ISOFLAVONES & & & & & \\ Diadzein (\(\upmu\) day\({}^{-1}\)) & 126.65 & 10.55 & 340.14 & 0.00 & 3654.46 \\ * Eq. E2 (pmol day\({}^{-1}\)) & 4.98 & 0.41 & 13.87 & — & 14.37 \\ Genistein (\(\upmu\) day\({}^{-1}\)) & 106.93 & 109.71 & 83.45 & 1.34 & 289.67 \\ Eq. E2 (pmol day\({}^{-1}\)) & 3.85 & 4.06 & 3.08 & 0.50 & 10.12 \\ Biochanin A (\(\upmu\) day\({}^{-1}\)) & 3.01 & 2.90 & 2.85 & 0.00 & 22.43 \\ Eq. E2 (pmol day\({}^{-1}\)) & 0.11 & 0.10 & 0.80 & — & 0.77 \\ Formonentie (\(\upmu\) day\({}^{-1}\)) & 106.80 & 110.60 & 85.04 & 1.37 & 247.66 \\ Eq. E2 (pmol day\({}^{-1}\)) & 3.97 & 4.11 & 3.16 & 0.05 & 9.21 \\ LIGNANS & & & & & \\ Enterolactone (\(\upmu\) day\({}^{-1}\)) & 182.57 & 147.24 & 171.69 & 0.19 & 813.13 \\ Eq. E2 (pmol day\({}^{-1}\)) & 6.12 & 4.94 & 5.95 & 0.006 & 21.25 \\ Enterodiol (\(\upmu\) day\({}^{-1}\)) & 134.57 & 121.78 & 118.29 & 0.16 & 648.71 \\ Eq. E2 (pmol day\({}^{-1}\)) & 4.45 & 4.03 & 3.91 & 0.005 & 21.45 \\ Secoisolaricresin (\(\upmu\) day\({}^{-1}\)) & 173.16 & 121.21 & 199.91 & 0.22 & 1389.96 \\ Eq. E2 (pmol day\({}^{-1}\)) & 4.18 & 3.34 & 5.52 & 0.006 & 38.36 \\ Matairesinol(\(\upmu\) day\({}^{-1}\)) & 22.96 & 18.26 & 24.12 & 0.00 & 199.17 \\ Eq. E2 (pmol day\({}^{-1}\)) & 0.64 & 0.51 & 0.67 & — & 5.56 \\ COUMESTANS & & & & & \\ Coumestrol (\(\upmu\) day\({}^{-1}\)) & 0.29 & 0.08 & 0.77 & 0.00 & 8.30 \\ Eq. E2 (pmol day\({}^{-1}\)) & 0.001 & 0.003 & 0.03 & — & 0.31 \\ \hline \end{tabular}  
* Total refers to pM of E2, with a mean of 28.28 (SD = 23.97) and median of 21.50.  
\end{table}