Impact of a soy drink on climacteric symptoms: an open-label, crossover, randomized clinical trial

The effect of soy isoflavones given to women in the climacteric period on menopausal symptoms and quality of life: Systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This systematic review and meta-analysis aimed to examine the effect of soy isoflavones on menopausal symptoms and quality of life in climacteric women.

METHOD

The literature search was conducted in PubMed, CINAHL, Scopus, and Science Citation Index (Web of Science) until September 2023. This study is based on the recommendations of the Cochrane guidelines. The data were analysed using the Review Manager computer software (Version 5.4). The methodological quality of the studies was assessed with the RoB-2 tool.

RESULTS

This analysis was completed with five studies and 425 climacteric women. According to the results of the analysis, menopausal symptoms (SMD: -0.49, 95 % CI: -1.13 to 0.16, Z = 1.47, p = 0.14), physical component (MD: -1.10, 95 % CI: -4.22 to 2.01, Z = 0.70, p = 0. 49) and mental component (MD: 0.81, 95 % CI: -6.73 to 8.35, Z = 0.21, p = 0.83), but there was a significant difference in depression level (SMD: -0.41, 95 % CI: -0.73 to -0.09, Z = 2.53, p = 0.01).

CONCLUSION

According to the results of the analysis, soy isoflavones had no effect on menopausal symptoms (vasomotor, psychosocial, physical, sexual, and urogenital complaints) and quality of life in climacteric women but did reduce the level of depression. There was a high risk of conflict of interest in the included studies.

PROSPERO DATABASE

Registration: CRD420234479700.

An Updated Review of Soy-Derived Beverages: Nutrition, Processing, and Bioactivity

The global market for plant-based drinks is experiencing rapid growth driven by consumer demand for more sustainable diets, including vegetarian and vegan options. Soy beverages in particular are gaining popularity among individuals with lactose intolerance and milk protein allergies. They are considered an excellent source of high-quality protein, vitamin B, unsaturated fatty acids, and beneficial phytochemicals such as phytosterols, soy lecithins, and isoflavones. This review presents a comprehensive market survey of fifty-two soy beverages available in Spain and other European countries. The predominant category among those evaluated was calcium and vitamin-fortified drinks, accounting for 60% of the market. This reflects the need to address the nutritional gap compared to cow's milk and meet essential dietary requirements. The review covers the technological aspects of industrial soy milk production, including both traditional methods and innovative processing techniques. Additionally, it analyzes multiple studies and meta-analyses, presenting compelling evidence for the positive effects of soy beverages on various aspects of health. The review specifically examines the contributions of different components found in soy beverages, such as isoflavones, proteins, fiber, and oligosaccharides. Moreover, it explores controversial aspects of soy consumption, including its potential implications for growth, puberty, fertility, feminization, and the thyroid gland.

The role of diet in managing menopausal symptoms: A narrative review

Menopause is a natural stage that occurs when women stop menstruating, during which many women experience physical and psychological symptoms that can affect their quality of life and ability to work. Dietary modifications and food supplements may be explored by some women as alternatives to hormone replacement therapy, although existing reviews and expert position statements have given this limited consideration. This narrative review summarises the current evidence for dietary patterns, and botanical and food supplements, in the management of common menopausal symptoms, including vasomotor symptoms (VMS; hot flushes; night sweats), changes in bodyweight and composition, psychological symptoms (depression; anxiety; cognitive changes), sleep disturbances, joint pain, skin changes and urogenital symptoms. Soy isoflavones may reduce the frequency and/or severity of VMS, although results are inconsistent, and it is unclear whether dietary and supplemental sources have comparable effects. Adopting a healthier dietary pattern may support a healthy bodyweight and benefit VMS. However, evidence suggesting dietary patterns may benefit depression, anxiety, and cognition remains largely observational. While some botanicals, such as black cohosh and St John's Wort, have been reported in some studies to alleviate symptoms (such as VMS and depression), these are not currently recommended due to uncertainty about the appropriate dose and preparation, and potential safety concerns. Evidence for other symptoms is currently too limited to draw conclusions. While further trials at different menopausal stages are needed, adopting a healthier dietary pattern in accordance with dietary guidelines is likely to help support women's health before, during and after the menopausal transition.

The Impact of Soy Isoflavone Supplementation on the Menopausal Symptoms in Perimenopausal and Postmenopausal Women

Introduction

Approximately one-third of a woman's life is spent in the menopausal phase. The unpleasant menopausal symptoms are unacceptable as a part of routine life. Indications of menopausal hormone therapy (MHT) are for alleviation of vasomotor symptoms, prevention of osteoporosis, and genitourinary symptoms associated with menopause. MHT is associated with an increased risk of breast cancer, cerebrovascular accidents, and coronary heart disease. Soy isoflavones have been extensively used as an alternative treatment in patients who cannot take MHT. The evidence of the efficacy of isoflavones in the literature is equivocal.

Aim

The aim of the study was to evaluate the efficacy of soy isoflavone supplementation on menopausal symptoms in perimenopausal and postmenopausal women and to evaluate the effect on blood pressure (BP) and body mass index (BMI).

Materials and Methods

A questionnaire-based prospective observational study was undertaken involving 39 perimenopausal and 61 postmenopausal women, who were prescribed 40 mg soy isoflavone supplements twice daily for 12 weeks. Menopause Rating Scale questionnaire was given to the patients before starting soy isoflavone therapy and at the end of the treatment; BP and BMI were also noted.

Results

The total score of both the groups was comparable at baseline. Among perimenopausal and postmenopausal women, the highest score was noted in symptoms of somatic domain. At the completion of our study, the total scores improved significantly by 38.6% and 33.3% in perimenopausal and postmenopausal women, respectively. The greatest improvement was seen in somatic subscale (42.5%) and psychological subscale (42.5%) and the least in urogenital subscale (16.1%) for perimenopausal women. For postmenopausal women, the greatest improvement was seen in psychological subscale (40.0%) and the least in urogenital subscale (14.2%).

Conclusion

Soy isoflavone supplementation is beneficial in both perimenopausal and postmenopausal women, more so in perimenopausal women. There is no beneficial effect of soy isoflavone supplementation on lowering systolic BP and BMI.

Current Perspectives on the Beneficial Effects of Soybean Isoflavones and Their Metabolites for Humans

Soybeans are rich in proteins and lipids and have become a staple part of the human diet. Besides their nutritional excellence, they have also been shown to contain various functional components, including isoflavones, and have consequently received increasing attention as a functional food item. Isoflavones are structurally similar to 17-β-estradiol and bind to estrogen receptors (ERα and ERβ). The estrogenic activity of isoflavones ranges from a hundredth to a thousandth of that of estrogen itself. Isoflavones play a role in regulating the effects of estrogen in the human body, depending on the situation. Thus, when estrogen is insufficient, isoflavones perform the functions of estrogen, and when estrogen is excessive, isoflavones block the estrogen receptors to which estrogen binds, thus acting as an estrogen antagonist. In particular, estrogen antagonistic activity is important in the breast, endometrium, and prostate, and such antagonistic activity suppresses cancer occurrence. Genistein, an isoflavone, has cancer-suppressing effects on estrogen receptor-positive (ER+) cancers, including breast cancer. It suppresses the function of enzymes such as tyrosine protein kinase, mitogen-activated kinase, and DNA polymerase II, thus inhibiting cell proliferation and inducing apoptosis. Genistein is the most biologically active and potent isoflavone candidate for cancer prevention. Furthermore, among the various physiological functions of isoflavones, they are best known for their antioxidant activities. S-Equol, a metabolite of genistein and daidzein, has strong antioxidative effects; however, the ability to metabolize daidzein into S-equol varies based on racial and individual differences. The antioxidant activity of isoflavones may be effective in preventing dementia by inhibiting the phosphorylation of Alzheimer's-related tau proteins. Genistein also reduces allergic responses by limiting the expression of mast cell IgE receptors, which are involved in allergic responses. In addition, they have been known to prevent and treat various diseases, including cardiovascular diseases, metabolic syndromes, osteoporosis, diabetes, brain-related diseases, high blood pressure, hyperlipidemia, obesity, and inflammation. Further, it also has positive effects on menstrual irregularity in non-menopausal women and relieving menopausal symptoms in middle-aged women. Recently, soybean consumption has shown steep increasing trend in Western countries where the intake was previously only 1/20-1/50 of that in Asian countries. In this review, I have dealt with the latest research trends that have shown substantial interest in the biological efficacy of isoflavones in humans and plants, and their related mechanisms.

Effects of a Cereal Bar with a Combination of Phytoestrogens on the Climacteric Symptoms: A Placebo-Controlled, Randomized Trial

OBJECTIVE

This study evaluated whether the consumption of a cereal bar combining different phytoestrogens could contribute to the reduction of climacteric symptoms in women.

METHODS

This is a clinical, prospective, randomized, simple-blind trial. Forty-eight women, aged 40-65 years, with climacteric symptoms, from a city in southwestern Paraná, Brazil. Participants were randomly assigned into two groups; Phytoestrogens group (PHY = 24), which received for 90-day period a cereal bar containing 80.73 milligrams of soybean and flaxseed phytoestrogens, and the placebo group (PLA = 24), which consumed rice flakes biscuit. Clinical, sociodemographic and anthropometric data were collected and climacteric symptoms were assessed using the Kupperman Index (KI).

RESULTS

Forty-three women were analyzed (PHY = 21 and PLA = 22). There were significant reductions in the overall KI score in both groups at the end of the intervention period (p < 0.05). However, the comparison between the groups using linear regression models presented expressively better symptom improvement in the PHY group -6.43 over time (95% CI: -11.6; -1.26; p < 0.05) KI points, with perimenopausal -15.15 (95% CI: -28.95; -1.35) and postmenopausal women -19.34 (95% CI: -33.68; -4.99) showed considerably greater reductions in symptoms at the end of the intervention period compared to premenopausal women. There was also significant reduction in symptoms of hot flushes, paresthesia, sexual complaints, insomnia and melancholy.

CONCLUSION

The consumption of a cereal bar containing phytoestrogens was able to improve the symptoms of climacteric syndrome.

Influence of dietary habits and Mediterranean diet adherence on menopausal symptoms. The FLAMENCO project

OBJECTIVE

To explore the association of dietary habits and Mediterranean diet adherence with menopausal symptoms.

METHODS

The present study included 172 women recruited from the FLAMENCO project. Menopausal symptoms were assessed with the Kupperman Menopausal Index and the Cervantes Menopause and Health Subscale from the validated Cervantes Scale. A food frequency questionnaire was employed to evaluate dietary habits. Adherence to the Mediterranean diet was assessed with the Mediterranean diet score.

RESULTS

Intake of poultry and skimmed dairy products was associated with a worse Kupperman Menopausal Index score (β: 0.17, P = 0.03 and β: 0.18, P = 0.01, respectively). On the contrary, soy milk consumption was associated with a better Kupperman Menopausal Index score (β: -0.17, P = 0.02). Poultry and skimmed dairy were associated with worse scores in the total Cervantes Menopause and Health Subscale score (β: 0.22, P = <0.01 and β: 0.19, P = 0.01, respectively), whereas soy milk and vegetables were associated with a better total Cervantes Menopause and Health Subscale score (β: -0.20, P = 0.01 and β: -0.17, P = 0.03, respectively). Regarding vasomotor symptoms, a greater consumption of poultry was associated with worse symptomatology (β: 0.18, P = 0.02), and soy milk consumption was associated with fewer vasomotor symptoms (β: -0.15, P = 0.04). In addition, women with numerous or severe vasomotor symptoms showed a greater consumption of skimmed dairy products (P < 0.05).

CONCLUSIONS

This study seems to indicate that some women with mild menopausal symptoms may derive benefit from lower consumption of poultry and skimmed dairy products and a greater consumption of vegetables and soy milk.

Effect of Short-Course Oral Ciprofloxacin on Isoflavone Pharmacokinetics following Soy Milk Ingestion in Healthy Postmenopausal Women

Soy isoflavones have several potential benefits related to postmenopausal health. Isoflavone glycosides, found predominantly in nonfermented soy products, e.g., soy milk, require conversion by gut microbiota to their respective bioavailable aglycones prior to absorption into portal circulation. Use of short-course oral ciprofloxacin for the treatment of acute uncomplicated cystitis, the incidence of which is increasing among postmenopausal women, might adversely affect gut microbiota. The objective of this one-group pre-post treatment study was to determine the effect of short-course oral ciprofloxacin on isoflavone pharmacokinetics in healthy postmenopausal women. Eleven postmenopausal subjects were assigned to consume a single oral dose of 375 mL UHT soy milk (SOY phase). Blood samples were collected immediately before soy milk ingestion and at specific times for 32 hours after soy milk ingestion. Following a washout period of at least seven days, subjects were assigned to take 250 mg oral ciprofloxacin after breakfast and dinner for three days, followed by a single oral dose of 375 mL UHT soy milk the next day (CIPRO/SOY phase). Blood samples were collected at the same time points as in the SOY phase. Plasma samples were treated with β-glucuronidase/sulfatase and plasma concentrations of aglycones (genistein and daidzein) were determined using high-performance liquid chromatography. Cmax, AUC0-t, and AUC0-∞ of both aglycones and Tmax of genistein obtained from the CIPRO/SOY phase were significantly lower than those obtained from the SOY phase, while Tmax of daidzein and t1/2 of both aglycones in the two phases were not significantly different.

Consumption of a soy drink has no effect on cognitive function but may alleviate vasomotor symptoms in post-menopausal women; a randomised trial

PURPOSE

Cognitive decline is commonly reported during the menopausal transition, with memory and attention being particularly affected. The aim of this study was to investigate the effects of a commercially available soy drink on cognitive function and menopausal symptoms in post-menopausal women.

METHODS

101 post-menopausal women, aged 44-63 years, were randomly assigned to consume a volume of soy drink providing a low (10 mg/day; control group), medium (35 mg/day), or high (60 mg/day) dose of isoflavones for 12 weeks. Cognitive function (spatial working memory, spatial span, pattern recognition memory, 5-choice reaction time, and match to sample visual search) was assessed using CANTAB pre- and post-the 12 week intervention. Menopausal symptoms were assessed using Greene's Climacteric Scale.

RESULTS

No significant differences were observed between the groups for any of the cognitive function outcomes measured. Soy drink consumption had no effect on menopausal symptoms overall; however, when women were stratified according to the severity of vasomotor symptoms (VMS) at baseline, women with more severe symptoms at baseline in the medium group had a significant reduction (P = 0.001) in VMS post-intervention (mean change from baseline score: - 2.15 ± 1.73) in comparison to those with less severe VMS (mean change from baseline score: 0.06 ± 1.21).

CONCLUSIONS

Soy drink consumption had no effect on cognitive function in post-menopausal women. Consumption of ~ 350 ml/day (35 mg IFs) for 12 weeks significantly reduced VMS in those with more severe symptoms at baseline. This finding is clinically relevant as soy drinks may provide an alternative, natural, treatment for alleviating VMS, highly prevalent among western women.

Low-flow ischaemia and reperfusion in rat hearts: energetic of stunning and cardioprotection of genistein

Objectives

Low-flow ischemia (LFI) is consequent to coronary disease and produces cardiac stunning during reperfusion (R). Energetic performance and mechanisms of Ca2+ handling during LFI/R are not known. Moreover, cardioprotection of the phytoestrogen genistein (Gen) remains to be demonstrated in LFI/R. The aim was to study the mechanisms of the stunning consequent to LFI/R and the effects of Gen on both sexes.

Methods

Rat ventricles were perfused inside a calorimeter to measure maximal pressure development (P) and total heat rate (Ht) before and during exposition to LFI/R. The mechanisms of stunning were evaluated with selective drugs.

Key findings

Female hearts (FH) developed higher postischemic contractile recovery (PICR) and muscle economy (P/Ht) than males (MH). Cardioprotection was sensitive to blockade of mKATP channels, UCam and NOS. Perfusion of 20 μmol/l Gen reduced PICR and P/Ht during LFI/R in FH, and dysfunction was increased by mNCX blockade with mPTP opening. However, intraperitoneal 5 mg/kg Gen (Gen-ip) was cardioprotective in both sexes, and the beneficial effect of Gen-ip was blocked by 100 μmol/l 5-HD.

Conclusions

FH are more protected than MH against the LFI/R dysfunction, which involves mitochondrial Ca2+ loss; Gen-ip was more cardioprotective in MH than in FH, mainly by activation of the mKATP channels.

Functional Food and Cardiovascular Disease Prevention and Treatment: A Review

Cardiovascular disease (CVD) is now the leading cause of death globally and is a growing health concern. Lifestyle factors, including nutrition, play an important role in the etiology and treatment of CVD. Functional foods based on their basic nutritional functions can decrease the risk of many chronic diseases and have some physiological benefits. They contain physiologically active components either from plant or animal sources, marketed with the claim of their ability to reduce heart disease risk, focusing primarily on established risk factors, which are hyperlipidemia, diabetes, metabolic syndrome, obesity/overweight, elevated lipoprotein A level, small dense low-density lipoprotein cholesterol (LDL-C), and elevated inflammatory marker levels. Functional foods are suspected to exert their cardioprotective effects mainly through blood lipid profile level and improve hypertension control, endothelial function, platelet aggregation, and antioxidant actions. Clinical and epidemiological observations indicate that vegetable and fruit fiber, nuts and seeds, sea foods, coffee, tea, and dark chocolate have cardioprotective potential in humans, as well whole-grain products containing intact grain kernels rich in fiber and trace nutrients. They are nutritionally more important because they contain phytoprotective substances that might work synergistically to reduce cardiovascular risk. This review will focus on the reciprocal interaction between functional foods and the potential link to cardiovascular health and the possible mechanisms of action.

Long-term exercise training and soy isoflavones to improve quality of life and climacteric symptoms

OBJECTIVE

To verify the efficacy of phytoestrogen supplementation combined with aerobic and resistance training on the improvement of climacteric symptoms and health-related quality of life (HRQoL) in postmenopausal women.

METHODS

From a pool of women who had participated in a 1-year intervention study and were randomly assigned to either exercise + phytoestrogen (EX + PHY) or exercise + placebo (EX + PL), a total of 31 healthy but overweight women (mean age 59.2 ± 4.8 years, body mass index 29.1 ± 3.5 kg/m2) finished the study (EX + PHY, n = 15; EX + PL, n = 16). All the following variables were measured before, after 6 months and after 12 months of intervention: body composition (fat and lean body mass, DXA), HRQoL (SF-36 questionnaire: physical and mental component summaries and subscales; and the 10-item Perceived Stress Scale questionnaire), climacteric symptoms (Kupperman Index questionnaire).

RESULTS

After 1 year of intervention, physical functioning (p = 0.003), role-emotional (p = 0.031), vitality (p = 0.007), and global health (p < 0.001) were significantly and similarly increased in both groups. Regarding climacteric symptoms, an improvement in the Kupperman index total score (p = 0.015) was observed.

CONCLUSION

Our results demonstrate that adding phytoestrogens to exercise training does not provide the additive effect for HRQoL in postmenopausal and overweight women. Moreover, exercise and phytoestrogen may interfere in the improvement of climacteric symptoms in the long term.