It is important to point out that the spine has a high proportion of trabecular bone and that this is probably the reason why the spine is thought to be more sensitive to isoflavones. In some cases the purported effect may depend on external cues, such as the amount of moonlight. In this line, three meta-analyses were conducted to study isoflavone consumption and endometrial cancer risk. In the last few decades, scientific evidence has stressed the importance of plants in the prevention and/or supportive treatment of a plethora of diseases, many of them chronic, age-associated disorders. 1Nutrition and Obesity Group, Department of Pharmacy and Food Science, University of the Basque Country (UPV/EHU) and Lucio Lascaray Research Institute, 01006 Vitoria, Spain; sue.uhe@zemog.aoias (S.G.-Z. A systematic review and meta-analysis of the effects of isoflavone formulations against estrogen-deficient bone resorption in peri- and postmenopausal women. Regarding blood pressure, inconsistent results were reported in three further interventional studies (n = 406 healthy, postmenopausal or obese participants aged 5079 years) either in diastolic or systolic blood pressure, after a supplementation with soy-protein. Regarding cancer, scientific evidence suggests that isoflavones could be useful in reducing the risk of suffering some types of cancer, such as breast and endometrial cancer, but further studies are needed to confirm these results. (2018), 30 articles were included for analysis; 15 of them were case-control studies, eight cohort studies and seven nested case-control studies [76]. The authors concluded that evidence for the role of isoflavones and soy products in the prevention of cardiovascular diseases was scarce and inconclusive. official website and that any information you provide is encrypted This is mainly due to their potential adverse effects, which range from increased coronary heart disease to stroke and cancer [53,85]. Lastly, with regard to isoflavone consumption safety, it seems that they are safe and that the most common adverse effect is mild and occurs at the gastrointestinal level. Abshirini M., Omidian M., Kord-Varkaneh H. Effect of soy protein containing isoflavones on endothelial and vascular function in postmenopausal women: A systematic review and meta-analysis of randomized controlled trials. The meta-analysis included 15 studies in which the number of participants ranged from 30 to 252. Ingram D., Sanders K., Kolybaba M., Lopez D. Case-control study of phyto-oestrogens and breast cancer. Considering the isoflavone chemical structure, potential health adverse effects of these compounds related to their estrogenic activity have been postulated, despite the scientific opinion offered by EFSA indicating that isoflavone intake was safe. (2016) conducted a meta-analysis of 18 studies involving 16,917 colorectal cancer cases in 559,486 participants [78]. and J.T. Changes to Earth's climate driven by increased human emissions of heat-trapping greenhouse gases are already having widespread effects on the environment: glaciers and ice sheets are shrinking, river and lake ice is breaking up earlier, plant and animal geographic ranges are shifting, and plants and trees are blooming sooner. In the meta-analysis reported by Applegate et al. (2016) suggested that a daily intake of soy isoflavones, ranging from 20 to 100 mg/day, reduced total cholesterol and triglyceride plasma concentrations, as well as some markers of oxidative stress (nitric oxide and malonaldehyde), thus reducing cardiovascular risk [52]. Magee P.J. Dietary intake of flavonoid subclasses and risk of colorectal cancer: Evidence from population studies. Before Looking at a few examples of moonlight's. There are a total of 15 3 = 3375 possible outcomes. The enzyme lactase-phlorizin hydrolase (LPH) deglycosylases phenolic compounds in the intestinal lumen, and after that, the aglycone form enters the epithelial cells by passive diffusion. With regard to isoflavone content in foodstuffs, it has been observed that in soybeans, the amount of these phenolic compounds ranges from 1.2 to 4.2 mg per g on dry weight, whereas in red clover, the amount varies between 10 and 25 mg per g on dry weight [15,16]. The majority of the studies that used display stimuli, such as photos, 3D images, virtual reality, and videos of natural landscapes, confirmed that viewing natural scenery led to more relaxed body responses than viewing the control. (2016) analyzed the effect of oral isoflavone supplementation on endometrial thickness in pre- and post-menopausal women, which is a biomarker for the proliferative effects of estrogens associated with an increased endometrial risk [72]. However, all the authors agree that further studies are necessary so as to confirm these results. Chen M.N., Lin C.C., Liu C.F. Focusing on the overall intake of isoflavones in humans, several studies have reported varied results. In this sense, Micek et al. Soy products (0.05130 g/day) and total isoflavones (0.28 to 63 mg/day). The two systematic reviews conclude that isoflavones have an important role in reducing hot flushes [52,53], although some observations need to be pointed out. Regarding cancer, scientific evidence suggests that isoflavones could be useful in reducing the risk of suffering some types of cancer, such as breast and endometrial cancer, but further studies are needed to confirm these results. However, a limitation in this field is that there is still a great heterogeneity among studies. Isoflavone excretion occurs mainly through urine and feces, primarily in the conjugate forms, and up to 95% takes place in 24 h [43]. Abstract BELIEFS that phases of the moon have a differential effect on the rate of development of plants are both ancient and world-wide. (2018) showed no effect of soy isoflavones on plasma concentrations of lipoprotein a (Lpa), a low-density lipoprotein associated with increased cardiovascular risk due to its pro-thrombotic and atherogenic properties [63]. Modified from Mace et al. They also note that the effects of isoflavones are greater when administered as aglycones. Perna et al. Thus, soybean can be considered as the best food source. On the contrary, a systematic review and meta-analysis reported by Man et al. Bacterial metabolites of isoflavones forming in the gut. Micek A., Godos J., Brzostek T., Gniadek A., Favari C., Mena P., Libra M., Del Rio D., Galvano F., Grosso G. Dietary phytoestrogens and biomarkers of their intake in relation to cancer survival and recurrence: A comprehensive systematic review with meta-analysis. After the consumption of around 17 mg of isoflavones per day, the median plasma concentrations of genistein, glycitein, daidzein and equol were 245.3 ng/mL, 9.8 ng/mL, 86.8 ng/mL and 12.7 ng/mL, respectively. Karr S.C., Lampe J.W., Hutchins A.M., Slavin J.L. Hosoda K., Furuta T., Yokokawa A., Ishii K. Identification and quantification of daidzein-7-glucuronide-4-sulfate, genistein-7-glucuronide-4-sulfate and genistein-4,7-diglucuronide as major metabolites in human plasma after administration of kinako. 19% reduction in endometrial cancer risk. Plasma isoflavone concentration is associated with decreased risk of type 2 diabetes in Korean women but not men: Results from the Korean Genome and Epidemiology Study. Plants grow best when the moon is in the waxing phase, when its gravitational pull is strongest. Further, Chalvon-Demersay et al. Produced metabolites appear in plasma at variable concentrations and can enter enterohepatic circulation [28]. In addition, genistein and glycitein are transformed into dihydrogenistein and dihydroglycitein, respectively, before being further converted into other metabolites. Estimated Asian adult soy protein and isoflavone intakes. Although results vary greatly, most of these applications are supported by at least a few clinical studies. Zamora-Ros R., Knaze V., Rothwell J.A., Hmon B., Moskal A., Overvad K., Tjnneland A., Kyr C., Fagherazzi G., Boutron-Ruault M.C., et al. (2016) also studied whether there was an association between different types of interventions and the reduction in hot flushes and night sweats [90]. For their meta-analysis, Jiang et al. The improvement was greater in treatments lasting more than one year and in subjects with normal weight, probably because subjects with excessive body weight have a lesser risk of bone loss. Chen L.R., Ko N.Y., Chen K.H. In general terms, caution should be exercised with the use of high doses of isoflavones in women with a family history of breast cancer [49]. (2017) conducted a meta-analysis with ten observational studies to assess the association between the isoflavone compounds daidzein, genistein and equol, and breast cancer [61]. Murota K., Nakamura Y., Uehara M. Flavonoid metabolism: The interaction of metabolites and gut microbiota. Publishers Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. As with other phenolic compounds, isoflavones can be presented as free forms (aglycones) or conjugated with carbohydrates (glycosides). ), 2CIBEROBN Physiopathology of Obesity and Nutrition, Institute of Health Carlos III, 01006 Vitoria, Spain, 3Bioaraba Health Research Institute, 01002 Vitoria, Spain. Gee J.M., DuPont M.S., Day A.J., Plumb G.W., Williamson G., Johnson I.T. HHS Vulnerability Disclosure, Help Equol has been considered as the most interesting colonic metabolite due to its beneficial biological activity, which differs from that of its precursor, daidzein [13,38,39]. Daily et al. Man B., Cui C., Zhang X., Sugiyama D., Barinas-Mitchell E., Sekikawa A. Finally, isoflavones could be useful in reducing hot flushes associated with menopause. They are present in several vegetables, mainly in legumes such as soy, white and red clover, alfalfa and beans. Li L., Xu L., Wu J., Dong L., Zhao S., Zheng Q. The results indicated that the isoflavone intake decreased the ovarian cancer risk by 33%. This difference could explain the slow effect of isoflavones in alleviating hot flushes. Conceptualization, S.G.-Z. . Akhlaghi M., Ghasemi Nasab M., Riasatian M., Sadeghi F. Soy isoflavones prevent bone resorption and loss, a systematic review and meta-analysis of randomized controlled trials. That's what behavioral ecologist Jenny York learned while studying white-browed sparrow weavers . This fact was not taken into account in previous meta-analyses, and thus it may justify the discrepancies amongst them. Is equol production beneficial to health? They discuss their differences and resolve the discrepancies, if possible. The four chemical forms of the three most abundant isoflavones. Sfakianos J., Coward L., Kirk M., Barnes S. Intestinal uptake and biliary excretion of the isoflavone genistein in rats. In this study, five prospective cohort studies and seven case-control studies, with 6275 cases and 393,776 controls, were included. In addition, several studies have observed that the urine excretion of daidzein metabolites is notably higher than that of genistein metabolites [44,45,46]. Dong J.Y., Qin L.Q. Therefore, it is necessary to support these results with additional studies. (2019) conducted a meta-analysis where 23 prospective studies with a total of 330,826 participants were included. Thanks for reading Scientific American. (2016) included 17 studies (nine case-control studies and eight cohort studies) [80]. van der Schouw Y.T., Kreijkamp-Kaspers S., Peeters P.H., Keinan-Boker L., Rimm E.B., Grobbee D.E. Messina M.J. Legumes and soybeans: Overview of their nutritional profiles and health effects. However, when a subgroup analysis by a class of flavonoids was carried out, they concluded that these inverse associations were significant for all categories of flavonoids except for isoflavones and flavonols. Regarding cancer, scientific evidence suggests that isoflavones could be useful in reducing the risk of suffering some types of cancer, such as breast and endometrial cancer, but further studies are needed to confirm these results. Therefore, the authors concluded that the intake of dietary isoflavones paid a protective role against ovarian cancer. In this systematic review, 123 studies were included, with a total number of 516,330 participants. The authors found a statistical inverse association between isoflavone consumption and colorectal cancer risk in case-control studies, although not in cohort studies. Contraction stimulates translocation of glucose transporter GLUT4 in skeletal muscle through a mechanism distinct from that of insulin. 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