Effects of Tea Consumption on Anthropometric Parameters, Metabolic Indexes and Hormone Levels of Women with Polycystic Ovarian Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Long-term consumption of green tea protects the mental health of middle-aged and older adult men by improving inflammation levels

Background

Middle-aged and older adult men are at a heightened risk of depression. Green tea, as a popular beverage, has drawn widespread attention for its health benefits. However, there remains controversy over the effects of green tea on combating depression and regulating hormones.

Objective

This study aimed to investigate the effects of long-term green tea consumption on depression levels, hormones, and brain structure in, middle-aged and older adult men.

Methods

A total of 280 volunteers participated in the study, divided into a tea-drinking group and a control group. Basic demographic information and biological marker data, as well as MRI data from some of the volunteers, were collected. A controlled study was conducted to explore the effects of long-term tea drinking on them.

Results

BMI (p = 0.002), depression level (p = 0.003), insomnia severity (p = 0.008), and systemic inflammation index (p = 0.009) were significantly lower in the tea drinking group, and their testosterone levels were significantly higher than those in the control group (p = 0.001). Moreover, GM volume in the right precuneus in the control group was significantly reduced compared with that in the tea drinking group.

Conclusion

Long-term tea consumption helps reduce BMI and increase testosterone levels in middle-aged and older adult men, and it can also reduce their risk of depression by lowering inflammation and improving sleep quality. Additionally, long-term tea consumption may have the potential to delay brain aging in middle-aged and older adult men.

Dietary supplements in polycystic ovary syndrome-current evidence

Polycystic ovary syndrome (PCOS) is the most prevalent endocrine disorder in women of reproductive age, and presents a significant challenge to the global population. This review provides comprehensive evidence of interventions, including food and dietary supplements, aimed at reversing PCOS and improving fertility outcomes. Various dietary supplements are known to cause metabolic changes and hormonal regulation and have a potential impact on increasing pregnancy rates. Although some biochemical alterations have been observed, these metabolic changes do not directly reverse the disorder. Moreover, the lack of sufficient evidence does not convince clinicians to standardize dietary supplements as alternatives to medical or pharmacological interventions. This calls for a study of women with PCOS taking dietary supplements. In addition, unbiased studies of combinations of treatment options for supplements, including large cohort clinical trials, will lead to evidence-based medicine.

Association of Herbal Tea and Follicle-Stimulating Hormone, Anthropometric Parameters, and Fasting Blood Glucose Levels Among Polycystic Ovarian Syndrome Women: A Systematic Review and Meta-Analysis of Clinical Trials

This systematic review and meta-analysis of randomized controlled trials (RCTs) aimed to test our hypothesis that herbal tea may improve anthropometric parameters, metabolic factors, and hormone levels in women with polycystic ovarian syndrome (PCOS). A literature search was conducted on Information Sciences Institute, Medline (PubMed), Scopus, Embase, and Google Scholar, up to March 2023 without applying language or date restrictions. RCTs that assigned herbal tea vs. placebo on PCOS women and evaluated changes in anthropometric measurements, metabolic indices, or hormonal profiles were included. Six RCTs with 235 PCOS women (119 in the intervention and 116 in the control group) were included. Meta-analysis showed that herbal tea consumption led to significant decreases in weight (weighted mean difference [WMD], -2.02 kg; 95% confidence interval [CI], -3.25, -0.80), body mass index (BMI) (WMD, -0.88 kg/m2; 95% CI, -1.47, -0.28) and fasting blood glucose (FBG) (WMD, -6.47 mg/dL; 95% CI, -8.49, -4.45), compared to the control group. Herbal tea supplementation has also significantly increased follicle-stimulating hormone (FSH) concentration (WMD, 0.56 IU/L; 95% CI, 0.17, 0.95). Meanwhile, the effect of herbal tea on the waist/hip ratio, hip circumference, waist circumference, body fat, fasting insulin, FBG/insulin ratio, luteinizing hormone, total testosterone, and dehydroepiandrosterone sulfate was not significant. Herbal tea might be a potential supplemental therapy to manage weight, BMI, FBG, and FSH in PCOS women. Further large randomized clinical trials are recommended to affirm these findings.

Could polyphenols be an effective treatment in the management of polycystic ovary syndrome?

Polycystic ovary syndrome (PCOS), is a health problem observed in women of reproductive age. Different diets, physical activity recommendations and lifestyle changes can be effective in dealing with the symptoms of PCOS. Nutrition is indeed an essential part of the treatment of the disease as it directly affects body weight loss, insulin resistance, lipid profile, hormones, and dermatological complaints such as acne. Polyphenols, simply classified as flavonoids and non-flavonoids, are bioactive components found in plant-based foods. The most common polyphenols in the diet are flavanols, flavonols, flavanone, anthocyanins. In particular, polyphenols which are compounds naturally found in foods, have antioxidant, anticancer, anti-inflammatory, antimutagenic benefits along with many other ones. In the treatment of PCOS, polyphenols may help reduce the symptoms, improve insulin resistance and poor lipid profile, and cure hormonal disorders. It has been reported that polyphenols are influential in menstrual cycle disorders and enable a decrease in body weight, hyperandrogenism, estrogen, testosterone, luteinizing hormone (LH)/follicle stimulating hormone (FSH) ratios and LH. For adequate daily intake of polyphenols, which are found in high amounts in fruits and vegetables, at least 5 portions of fruits and vegetables should be consumed in addition to a healthy nutrition pattern. In this review, the effects of various polyphenols on polycystic ovary syndrome are discussed.

The effect of green tea supplementation on the anthropometric outcomes in overweight and obese women: a time and dose-response meta-analysis of randomized controlled trials

Inconsistencies are evident within the literature regarding the role of Green Tea (GT) supplementation on women living with obesity. To address this, we conducted to determine the impact of GT supplementation on the weight, body mass index (BMI), and waist circumference (WC) in overweight and obese women using time and dose-response meta-analysis of randomized controlled trials (RCTs). This meta-analysis searched electronic Scopus, Web of Science, Embase, and PubMed/Medline databases from inception to December 1st, 2022. Data were reported as weighted mean difference (WMD) with 95% confidence interval (CI). A total of 2061 references were identified, and 15 articles with 16 RCT arms on body weight, 17 RCT arms on BMI, and 7 RCT arms on WC were included in the meta-analysis. GT supplementation significantly decreases body weight (WMD: -1.23 kg, 95% CI: -2.13 to -0.33, p = 0.007), BMI (WMD: -0.47 kg/m2, 95% CI: -0.87 to -0.07, p = 0.020) and WC (WMD: -3.46 cm, 95% CI: -6.75 to -0.16, p = 0.040). In subgroup analyses, GT consumption demonstrated lowered body weight with dosaes ≥1000 mg/day (WMD: -1.38 kg), in the RCTs, which lasted ≥8 wk (WMD: -1.24 kg). The non-linear dose-response assessment detected a negative correlation between the changes in body weight and BMI in green tea consumption of more than 1000 (mg/day). The GT supplementation reduced the weight, BMI, and WC in overweight and obese women. In clinical practice, healthcare professionals can recommend using GT with dosages ≥ 1000mg/day and duration ≥ 8 wk in obese women.

Habitual Tea Consumption Increases the Incidence of Metabolic Syndrome in Middle-Aged and Older Individuals

In middle-aged and elderly individuals, the relationship between tea consumption and incident metabolic syndrome (MetS) is still unclear. Therefore, this study intends to figure out the relationship between tea-drinking frequency and MetS in rural middle-aged and older Chinese residents. In the Northeast China Rural Cardiovascular Health Study, 3632 middle-aged or older individuals (mean age 57 ± 8, 55.2% men) without MetS were included at baseline during 2012–2013 and were followed up on between 2015–2017. Participants showing differential tea consumption frequency were divided into the following classes: non-habitual tea drinkers, occasional tea drinkers, 1–2 times/day drinkers, and ≥3 times/day drinkers. Data showed that non-habitual tea drinking was more common among women. The frequency of tea consumption was higher in ethnic groups other than Han and among singles, as well as in concurrent smokers and drinkers and individuals with primary or lower educational status. The increasing tea consumption was in line with baseline elevations in body mass index, systolic and diastolic blood pressure, high-density lipoprotein cholesterol (HDL-C), and AST/ALT ratio. Multivariate logistic regression analysis confirmed that occasional tea drinking increased the incidence of low HDL-C [OR (95% CI): 1.268 (1.015, 1.584)], high waist circumference [OR (95% CI): 1.336 (1.102, 1.621)], and MetS [OR (95% CI): 1.284 (1.050, 1.570)]. In addition, 1–2 times/day tea drinking increased the cumulative incidence of high TG [OR (95% CI): 1.296 (1.040, 1.616)], high waist circumference [OR (95% CI): 1.296 (1.044, 1.609)] and MetS [OR (95% CI): 1.376 (1.030, 1.760)]. We demonstrated that regular tea consumption is correlated with a greater incidence of metabolic disorders and MetS. Our findings may help clarify the contradictory association reported between tea drinking and MetS development in middle-aged and older residents of rural China.